HCS515/SL - MICROCHIP TECHNOLOGY

HCS515

FEATURES

Security

• Encrypted storage of manufacturer’s code

• Encrypted storage of encoder decryption keys

• Up to seven transmitters can be learned code

hopping technology

• Normal and secure learning mechanisms

Operating

• 4.5V – 5.5V operation

• Internal oscillator

• Auto bit rate detection

Other

• Stand-alone decoder

• Internal EEPROM for transmitter storage

• Synchronous serial interface

• 1 Kbit user EEPROM

• 14-pin DIP/SOIC package

Typical Applications

• Automotive remote entry systems

• Automotive alarm systems

• Automotive immobilizers

• Gate and garage openers

• Electronic door locks

• Identity tokens

• Burglar alarm systems

Compatible Encoders

All encoders and transponders configured for the fol-

lowing setting:

• PWM modulation format (1/3-2/3)

•T

E in the range from 100 μs to 400 μs

• 10 x TE Header

• 28-bit Serial Number

• 16-bit Synchronization counter

• Discrimination bits equal to Serial Number 8 LSbs

• 66- to 69-bit length code word.

DESCRIPTION

The Microchip Technology Inc. HCS515 is a code hop-

ping decoder designed for secure Remote Keyless

Entry (RKE) systems. The HCS515 utilizes the pat-

ented code hopping system and high security learning

mechanisms to make this a canned solution when used

with the HCS encoders to implement a unidirectional

remote and access control systems. The HCS515 can

be used as a stand-alone decoder or in conjunction

with a microcontroller.

PACKAGE TYPE

BLOCK DIAGRAM

The manufacturer’s code, encoder decryption keys,

and synchronization information are stored in

encrypted form in internal EEPROM. The HCS515

uses the S_DAT and S_CLK inputs to communicate

with a host controller device.

The HCS515 operates over a wide voltage range of

4.5V – 5.5V. The decoder employs automatic bit rate

detection, which allows it to compensate for wide vari-

HCS515

PDIP, SOIC

VDD

Vss

RF_IN

MCLR

S_CLK

S_DAT

Reception Register

Internal CONTROL

DECRYPTOR

RFIN

OSCILLATOR

S_DAT

S_CLK

MCLR

EEPROM

EE_DAT

EE_CLK

KEELOQ® Code Hopping Decoder

HCS515

ations in transmitter data rate. The decoder contains

sophisticated error checking algorithms to ensure only

valid codes are accepted.

1.0 SYSTEM OVERVIEW

Key Terms

The following is a list of key terms used throughout this

data sheet. For additional information on KEELOQ® and

Code Hopping, refer to Technical Brief 3 (TB003).

•RKE - Remote Keyless Entry

•Button Status - Indicates what button input(s)

activated the transmission. Encompasses the 4

button status bits S3, S2, S1 and S0 (Figure 7-2).

•Code Hopping - A method by which a code,

viewed externally to the system, appears to

change unpredictably each time it is transmitted.

•Code word - A block of data that is repeatedly

transmitted upon button activation (Figure 7-1).

•Transmission - A data stream consisting of

repeating code words (Figure 7-1).

•Crypt key - A unique and secret 64-bit number

used to encrypt and decrypt data. In a symmetri-

cal block cipher such as the KEELOQ algorithm,

the encryption and decryption keys are equal and

will therefore be referred to generally as the crypt

key.

•Encoder - A device that generates and encodes

data.

•Encryption Algorithm - A recipe whereby data is

scrambled using a crypt key. The data can only be

interpreted by the respective decryption algorithm

using the same crypt key.

•Decoder - A device that decodes data received

from an encoder.

•Decryption algorithm - A recipe whereby data

scrambled by an encryption algorithm can be

unscrambled using the same crypt key.

•Learn – Learning involves the receiver calculating

the transmitter’s appropriate crypt key, decrypting

the received hopping code and storing the serial

number, synchronization counter value and crypt

key in EEPROM. The KEELOQ product family facil-

itates several learning strategies to be imple-

mented on the decoder. The following are

examples of what can be done.

-Simple Learning

The receiver uses a fixed crypt key, common

to all components of all systems by the same

manufacturer, to decrypt the received code

word’s encrypted portion.

-Normal Learning

The receiver uses information transmitted

during normal operation to derive the crypt

key and decrypt the received code word’s

encrypted portion.

-Secure Learn

The transmitter is activated through a special

button combination to transmit a stored 60-bit

seed value used to generate the transmitter’s

crypt key. The receiver uses this seed value

to derive the same crypt key and decrypt the

received code word’s encrypted portion.

•Manufacturer’s code – A unique and secret 64-

bit number used to generate unique encoder crypt

keys. Each encoder is programmed with a crypt

key that is a function of the manufacturer’s code.

Each decoder is programmed with the manufac-

turer code itself.

1.1 HCS Encoder Overview

The HCS encoders have a small EEPROM array which

must be loaded with several parameters before use.

The most important of these values are:

• A crypt key that is generated at the time of pro-

duction

• A 16-bit synchronization counter value

• A 28-bit serial number which is meant to be

unique for every encoder

The manufacturer programs the serial number for each

encoder at the time of production, while the ‘Key Gen-

eration Algorithm’ generates the crypt key (Figure 1-1).

Inputs to the key generation algorithm typically consist

of the encoder’s serial number and a 64-bit manufac-

turer’s code, which the manufacturer creates.

Note: The manufacturer code is a pivotal part of

the system’s overall security. Conse-

quently, all possible precautions must be

taken and maintained for this code.

HCS515

FIGURE 1-1: CREATION AND STORAGE OF CRYPT KEY DURING PRODUCTION

The 16-bit synchronization counter is the basis behind

the transmitted code word changing for each transmis-

sion; it increments each time a button is pressed. Due

to the code hopping algorithm’s complexity, each incre-

ment of the synchronization value results in greater

than 50% of the bits changing in the transmitted code

word.

Figure 1-2 shows how the key values in EEPROM are

used in the encoder. Once the encoder detects a button

press, it reads the button inputs and updates the syn-

chronization counter. The synchronization counter and

crypt key are input to the encryption algorithm and the

output is 32 bits of encrypted information. This data will

change with every button press, its value appearing

externally to ‘randomly hop around’, hence it is referred

to as the hopping portion of the code word. The 32-bit

hopping code is combined with the button information

and serial number to form the code word transmitted to

the receiver. The code word format is explained in

greater detail in Section 7.2.

A receiver may use any type of controller as a decoder,

but it is typically a microcontroller with compatible firm-

ware that allows the decoder to operate in conjunction

with an HCS515 based transmitter. Section 3.0

provides detail on integrating the HCS515 into a sys-

tem.

A transmitter must first be ‘learned’ by the receiver

before its use is allowed in the system. Learning

includes calculating the transmitter’s appropriate crypt

key, decrypting the received hopping code and storing

the serial number, synchronization counter value and

crypt key in EEPROM.

In normal operation, each received message of valid

format is evaluated. The serial number is used to deter-

mine if it is from a learned transmitter. If from a learned

transmitter, the message is decrypted and the synchro-

nization counter is verified. Finally, the button status is

checked to see what operation is requested. Figure 1-3

shows the relationship between some of the values

stored by the receiver and the values received from

the transmitter.

FIGURE 1-2: BUILDING THE TRANSMITTED CODE WORD (ENCODER)

Transmitter

Manufacturer’s

Serial Number

Code

Crypt

Key

Generation

Algorithm

Serial Number

Crypt Key

Sync Counter

HCS515

Production

Programmer EEPROM Array

Button Press

Information

EEPROM Array

32 Bits

Encrypted Data

Serial Number

Transmitted Information

Crypt Key

Sync Counter

Serial Number

KEELOQ®

Encryption

Algorithm

HCS515

FIGURE 1-3: BASIC OPERATION OF RECEIVER (DECODER)

NOTE: Circled numbers indicate the order of execution.

2.0 PIN ASSIGNMENT

Button Press

Information

EEPROM Array

Manufacturer Code

32 Bits of

Encrypted Data

Serial Number

Received Information

Decrypted

Synchronization

Counter

Check for

Match

Sync Counter

Serial Number

KEELOQ®

Decryption

Algorithm

Check for

Match

Perform Function

Indicated by

button press

Crypt Key

PIN Decoder

Function I/O(1) Buffer

Type(1) Description

1 NC — — No connection

2 NC — — No connection

DD — — Power connection

4 S1 O TTL S1 function output

5 S0 O TTL S0 function output

6MCLR I ST Master clear input

7 NC — — No connection

8 NC — — No connection

9 S_DAT I/O TTL Synchronous data from controller

10 S_CLK I TTL Synchronous clock from controller

11 RF_IN I TTL Input from RF receiver

12 GND — — Ground connection

13 NC — — No connection

14 NC — — No connection

Note: P = power, I = in, O = out, and ST = Schmitt Trigger input.

HCS515

3.0 DECODER OPERATION

3.1 Learning a Transmitter to a

Receiver (Normal or Secure Learn)

Before the transmitter and receiver can work together,

the receiver must first ‘learn’ and store the following

information from the transmitter in EEPROM:

• A check value of the serial number

• The encoder decryption key

• The current synchronization counter value

The decoder must also store the manufacturer’s code

(Section 1.1) in protected memory. This code will

typically be the same for all of the decoders in a sys-

tem.

The HCS515 has seven memory slots, and, conse-

quently, can store up to seven transmitters. During the

learn procedure, the decoder searches for an empty

memory slot for storing the transmitter’s information.

When all of the memory slots are full, the decoder will

overwrite the last transmitter’s information. To erase all

of the memory slots at once, use the ERASE_ALL

command (C3H).

3.1.1 LEARNING PROCEDURE

Learning is initiated by sending the

ACTIVATE_LEARN (D2H) command to the decoder.

The decoder acknowledges reception of the command

by pulling the data line high.

For the HCS515 decoder to learn a new transmitter, the

following sequence is required:

1. Activate the transmitter once.

2. Activate the transmitter a second time. (In

Secure Learning mode, the seed transmission

must be transmitted during the second stage of

learn by activating the appropriate buttons on

the transmitter.)

3. The HCS515 will transmit a learn-status string,

indicating that the learn was successful.

4. The decoder has now learned the transmitter.

5. Repeat steps 1-3 to learn up to seven

transmitters

Note 1: Learning will be terminated if two

nonsequential codes were received or

if two acceptable codes were not

decoded within 30 seconds.

2: If more than seven transmitters are

learned, the new transmitter will

replace the last transmitter learned. It

is, therefore, not possible to erase lost

transmitters by repeatedly learning

new transmitters. To remove lost or

stolen transmitters, ERASE_ALL

transmitters and relearn all available

transmitters.

3: Learning a transmitter with an encoder

decryption key that is identical to a

transmitter already in memory

replaces the existing transmitter. In

practice, this means that all transmit-

ters should have unique encoder

decryption keys. Learning a previously

learned transmitter does not use any

additional memory slots.

The following checks are performed by the decoder to

determine if the transmission is valid during learn:

• The first code word is checked for bit integrity.

• The second code word is checked for bit integrity.

• The encoder decryption key is generated accord-

ing to the selected algorithm.

• The hopping code is decrypted.

• The discrimination value is checked.

• If all the checks pass, the key, serial number

check value, and synchronization counter values

are stored in EEPROM memory.

Figure 3-1 shows a flow chart of the learn sequence.

FIGURE 3-1: LEARN SEQUENCE

Enter Learn

Mode

Wait for Reception

of Second

Compare Discrimination

Value with Serial Number

Use Generated Key

to Decrypt

Equal?

Sync. Counter Value

Encoder Decryption Key

Exit

Learn Successful Store: Learn

Unsuccessful

Yes

Wait for Reception

of a Valid Code

Non-Repeated

Valid Code

Generate Key

from Serial Number/

Seed Value

Serial Number Check Value

HCS515

3.2 Validation of Codes

The decoder waits for a transmission and checks the

serial number to determine if it is a learned transmitter.

If it is, it takes the code hopping portion of the transmis-

sion and decrypts it, using the encoder decryption key.

It uses the discrimination value to determine if the

decryption was valid. If everything up to this point is

valid, the synchronization counter value is evaluated.

3.3 Validation Steps

Validation consists of the following steps:

1. Search EEPROM to find the Serial Number

Check Value Match

2. Decrypt the Hopping Code

3. Compare the 10 bits of the discrimination value

with the lower 10 bits of serial number

4. Check if the synchronization counter value falls

within the first synchronization window.

5. Check if the synchronization counter value falls

within the second synchronization window.

6. If a valid transmission is found, update the

synchronization counter, else use the next

transmitter block, and repeat the tests.

FIGURE 3-2: DECODER OPERATION

Transmission

Received?

Does

Ser # Check Val

Match?

Decrypt Transmission

decryption

valid?

Counter within

16?

Counter within

16K?

Update

Counter

Execute

Command

Save Counter

in Temp Location

Start

Yes

and

HCS515

3.4 Synchronization with Decoder

(Evaluating the Counter)

The KEELOQ technology patent scope includes a

sophisticated synchronization technique that does not

require the calculation and storage of future codes. The

technique securely blocks invalid transmissions while

providing transparent resynchronization to transmitters

inadvertently activated away from the receiver.

Figure 3-3 shows a 3-partition, rotating synchronization

window. The size of each window is optional but the

technique is fundamental. Each time a transmission is

authenticated, the intended function is executed and

the transmission's synchronization counter value is

stored in EEPROM. From the currently stored counter

value there is an initial "Single Operation" forward win-

dow of 16 codes. If the difference between a received

synchronization counter and the last stored counter is

within 16, the intended function will be executed on the

single button press and the new synchronization coun-

ter will be stored. Storing the new synchronization

counter value effectively rotates the entire synchroniza-

tion window.

A "Double Operation" (resynchronization) window fur-

ther exists from the Single Operation window up to 32K

codes forward of the currently stored counter value. It

is referred to as "Double Operation" because a trans-

mission with synchronization counter value in this win-

dow will require an additional, sequential counter

transmission prior to executing the intended function.

Upon receiving the sequential transmission the

decoder executes the intended function and stores the

synchronization counter value. This resynchronization

occurs transparently to the user as it is human nature

to press the button a second time if the first was unsuc-

cessful.

The third window is a "Blocked Window" ranging from

the double operation window to the currently stored

synchronization counter value. Any transmission with

synchronization counter value within this window will

be ignored. This window excludes previously used,

perhaps code-grabbed transmissions from accessing

the system.

FIGURE 3-3: SYNCHRONIZATION WINDOW

Blocked

Entire Window

rotates to eliminate

use of previously

used codes

Single Operation

Window

(32K Codes)

(16 Codes)

Double Operation

(resynchronization)

Window

(32K Codes)

Stored

Synchronization

Counter Value

HCS515

4.0 INTERFACING TO A

MICROCONTROLLER

The HCS515 interfaces to a microcontroller via a syn-

chronous serial interface. A clock and data line are

used to communicate with the HCS515. The microcon-

troller controls the clock line. There are two groups of

data transfer messages. The first is from the decoder

whenever the decoder receives a valid transmission.

The decoder signals reception of a valid code by taking

the data line high (maximum of 500 ms) The microcon-

troller then services the request by clocking out a data

string from the decoder. The data string contains the

function code, the status bit, and block indicators. The

second is from the controlling microcontroller to the

decoder in the form of a defined command set.

Figure 4-1 shows the HCS515 decoder and the I/O

interface lines necessary to interface to a microcon-

troller.

4.1 Valid Transmission Message

The decoder informs the microcontroller of a valid

transmission by taking the data line high for up to

500 ms. The controlling microcontroller must acknowl-

edge by taking the clock line high. The decoder then

takes the data line low. The microcontroller can then

begin clocking a data stream out of the HCS515. The

data stream consists of:

• START bit ‘0’.

• 2 status bits [REPEAT, Vlow].

• 4-bit function code [S3 S2 S1 S0].

•STOP bit ‘

1’.

• 4 bits indicating the number of transmitters

learned into the decoder [CNT3…CNT0].

• 4 bits indicating which block was used

[TX3…TX0].

• 64 bits of the received transmission with the hop-

ping code decrypted.

Note: Data is always clocked in/out Least

Significant bit (LSb) first.

The decoder will terminate the transmission of the data

stream at any point where the clock is kept low for lon-

ger than 1 ms. Therefore, the microcontroller can only

clock out the required bits. A maximum of 80 bits can

be clocked out of the decoder.

FIGURE 4-1: HCS515 DECODER AND I/O INTERFACE LINES

FIGURE 4-2: DECODER VALID TRANSMISSION MESSAGE

VDD

RF DATA

SYNC CLOCK

SYNC DATA

S0 OUTPUT

HCS515

MCLR

VSS

RF_IN

S_CLK

S_DAT

VCC

MICRO RESET

S1 OUTPUT

Decoder Signal Valid

TCLKH TDS

AB Cii

TACT

TDHI

TCLA

Received String

S_DAT TX0 TX3 RX63REPT VLOW S0 S1 S2 S3 CNT0 CNT30RX0 RX1 RX621

S_CLK

Information

TACK

TCLKH

TCLKL

Transmission

HCS515

4.2 Command Mode

4.2.1 MICROCONTROLLER COMMAND

MODE ACTIVATION

The microcontroller command consists of four parts.

The first part activates the Command mode, the sec-

ond part is the actual command, the third is the address

accessed, and the fourth part is the data. The micro-

controller starts the command by taking the clock line

high for up to 500 ms. The decoder acknowledges the

start-up sequence by taking the data line high. The

microcontroller takes the clock line low, after which the

decoder will take the data line low, tri-state the data line

and wait for the command to be clocked in. The data

must be set up on the rising edge and will be sampled

on the falling edge of the clock line.

4.2.2 COLLISION DETECTION

The HCS515 uses collision detection to prevent

clashes between the decoder and microcontroller.

Whenever the decoder receives a valid transmission

the following sequence is followed:

• The decoder first checks to see if the clock line is

high. If the clock line is high, the valid transmis-

sion notification is aborted, and the microcon-

troller Command mode request is serviced.

• The decoder takes the data line high and checks

that the clock line doesn’t go high within 50 μs. If

the clock line goes high, the valid transmission

notification is aborted and the Command mode

request is serviced.

• If the clock line goes high after 50 μs but before

500 ms, the decoder will acknowledge by taking

the data line low.

• The microcontroller can then start to clock out the

80-bit data stream of the received transmission.

FIGURE 4-3: MICROCONTROLLER COMMAND MODE ACTIVATION

MSB

Command ByteSTART Command

CLKL

CLKH

LSB

START

CMD

DATA

Address Byte

ata Byte

ADDR

REQ

RESP

CLK

Data

MSBLSB

ACK

HCS515

Data

HCS515

4.2.3 COMMAND ACTIVATION TIMES

The command activation time (Table 4-1) is defined as

the maximum time the microcontroller has to wait for a

response from the decoder. The decoder will abort and

service the command request. The response time

depends on the state of the decoder when the Com-

mand mode is requested.

TABLE 4-1: COMMAND ACTIVATION TIMES

4.2.4 DECODER COMMANDS

The command byte specifies the operation required by

the controlling microcontroller. Table 4-2 lists the com-

mands.

TABLE 4-2: DECODER COMMANDS

Decoder State Min Max

While receiving transmissions — 2.5 ms BPWMAX = 2.7 ms

During the validation of a received transmission — 3 ms

During the update of the sync counters — 40 ms

During learn — 170 ms

Instruction Command Byte Operation

READ F0 HEX Read a byte from user EEPROM

WRITE E1 HEX Write a byte to user EEPROM

ACTIVATE_LRN D2 HEX Activate a learn sequence on the decoder

ERASE_ALL C3 HEX Activate an erase all function on the decoder

PROGRAM B4 HEX Program manufacturer’s code and configuration byte

HCS515

4.2.5 READ BYTE/S FROM USER

EEPROM

The read command (Figure 4-4) is used to read bytes

from the user EEPROM. The offset in the user

EEPROM is specified by the address byte, which is

truncated to 7 bits (C to D). After the address, a dummy

byte must be clocked in (D to E). The EEPROM data

byte is clocked out on the next rising edge of the clock

line with the Least Significant bit first (E to F). Sequen-

tial reads are possible by repeating sequence E to F

within 1 ms after the falling edge of the previous byte’s

Most Significant bit (MSb). During the sequential read,

the address value will wrap after 128 bytes. The

decoder will terminate the read command if no clock

pulses are received for a period longer than 1.2 ms.

4.2.6 WRITE BYTE/S TO USER EEPROM

The write command (Figure 4-5) is used to write a loca-

tion in the user EEPROM. The address byte is trun-

cated to seven bits (C to D). The data is clocked in

Least Significant bit (LSb) first. The clock line must be

asserted to initiate the write. Sequential writes of bytes

are possible by clocking in the byte and then asserting

the clock line (D – F). The decoder will terminate the

write command if no clock pulses are received for a

period longer than 1.2 ms After a successful write

sequence, the decoder will acknowledge by taking the

data line high and keeping it high until the clock line

goes low.

FIGURE 4-4: READ BYTES FROM USER EEPROM

FIGURE 4-5: WRITE BYTES TO USER EEPROM

Decoder DATA

MSB

Command Byte

START Command

LSB

TRD

Address Byte Dummy Byte

CLK

μC DATA

Data Byte

MSBLSB MSBLSB

MSB

LSB

TRD

Decoder DATA

MSB

Command Byte

START Command

LSB

TWR

Address Byte Data Byte

CLK

μC DATA

Acknowledge

MSBLSB MSBLSB

TACK

TRESP

TACK2

HCS515

4.2.7 ERASE ALL

The erase all command (Figure 4-6) erases all the

transmitters in the decoder. After the command and two

dummy bytes are clocked in, the clock line must be

asserted to activate the command. After a successful

completion of an erase all command, the data line is

asserted until the clock line goes low.

FIGURE 4-6: ERASE ALL

4.2.8 ACTIVATE LEARN

The activate learn command (Figure 4-7) is used to

activate a transmitter learning sequence on the

decoder. The command consists of a Command mode

activation sequence, a command byte, and two dummy

bytes. The decoder will respond by taking the data line

high to acknowledge that the command was valid and

that learn is active.

Upon reception of the first transmission, the decoder

will respond with a learn status message (Figure 4-8).

During learn, the decoder will acknowledge the recep-

tion of the first transmission by taking the data line high

for 60 ms. The controlling microcontroller can clock out

at most 8 bits, which will all be zeros. All of the bits of

the status byte are zero, and this is used to distinguish

between a learn time-out status string and the first

transmission received string. The controlling microcon-

troller must ensure that the clock line does not go high

60 ms after the falling edge of the data line, for this will

terminate learn.

Upon reception of the second transmission, the

decoder will respond with a learn status message

(Figure 4-9).

The learn status message after the second transmis-

sion consists of the following:

• 1 START bit.

• The function code [S3:S0] of the message is

zero, indicating that this is a status string.

• The RESULT bit indicates the result of the learn

sequence. The RESULT bit is set if successful

and cleared otherwise.

• The OVR bit will indicate whether an exiting trans-

mitter is over written. The OVR bit will be set if an

existing transmitter is learned over.

•The [

CNT3…CNT0] bits will indicate the number of

transmitters learned on the decoder.

•The [

TX3…TX0] bits indicate the block number

used during the learning of the transmitter.

FIGURE 4-7: LEARN MODE ACTIVATION

Decoder DATA

MSB

Command Byte

START Command

LSB

TERA

Subcommand Byte Dummy Byte

CLK

μC DATA

Acknowledge

MSBLSB MSBLSB

TACK

TRESP

TACK2

ecoder DATA

MSB

Command Byte

START Command

LSB

TLRN

Dummy Byte Dummy Byte

CLK

μC DATA

Acknowledge

MSBLSB MSBLSB

TACK

TRESP

TACK2

HCS515

FIGURE 4-8: LEARN STATUS MESSAGE AFTER FIRST TRANSMISSION

FIGURE 4-9: LEARN STATUS MESSAGE AFTER SECOND TRANSMISSION

4.3 Stand-Alone Mode

The HCS515 decoder can also be used in stand-alone

applications. The HCS515 will activate the data line for

up to 500 ms if a valid transmission was received, and

this output can be used to drive a relay circuit. To acti-

vate learn or erase all commands, a button must be

connected to the CLK input. User feedback is indicated

on an LED connected to the S_DAT output line. If the

CLK line is pulled high, using the learn button, the LED

will switch on. After the CLK line is kept high for longer

than 2 seconds, the decoder will switch the LED line off,

indicating that learn will be entered if the button is

released. If the CLK line is kept high for another 6 sec-

onds, the decoder will activate an ERASE_ALL com-

mand.

Learn mode can be aborted by taking the clock line

high until the data line goes high (LED switches on).

During learn, the data line will give feedback to the user

and, therefore, must not be connected to the relay drive

circuitry.

Note: The Repeat bit must be cleared in the

configuration byte in Stand-alone

mode.

After taking the clock low and before a transmitter is

learned, any low-to-high change on the clock line may

terminate learn. This has learn implications when a

switch with contact bounce is used.

4.4 Erase All Command and Erase

Command

The Table 4-3 describes two versions of the Erase All

command.

Subcommand 01 can be used where a transmitter with

permanent status is implemented in the microcontroller

software. Use of subcommand 01 ensures that the

permanent transmitter remains in memory even when

all other transmitters are erased. The first transmitter

learned after any of the following events is the first

transmitter in memory and becomes the permanent

transmitter:

1. Programming of the manufacturer’s code.

2. Erasing of all transmitters

(subcommand 00 only).

Command Request

TCLKL

TCLKH

TACT

TCLL

TDHI

TCLA TCLH

CLK

Decoder 0 0 0 0 0 00 0

Status Byte

Data

Communications Request

TCLKL

TCLKH

TACT

AB CII

TCLL

TDHI

TCLA TCLH

CLK

Decoder TX0 TX3 RX63OVR RSLT 00 0 0 CNT0 CNT30RX0 RX1 RX62

Learn Status Bits Decoded TX

DATA

TABLE 4-3: ERASE ALL COMMAND

Command

Byte

Subcommand

Byte Description

C3 HEX 00 HEX Erase all

transmitters.

C3 HEX 01 HEX

Erase all transmit-

ters except 1. The

first transmitter in

memory is not

erased.

HCS515

4.5 Test Mode

A special Test mode is activated after:

1. Programming of the manufacturer’s code.

2. Erasing of all transmitters.

Test mode can be used to test a decoder before any

transmitters are learned on it. Test mode enables test-

ing of decoders without spending the time to learn a

transmitter. Test mode is terminated after the first suc-

cessful learning of an ordinary transmitter. In test

mode, the decoder responds to a test transmitter. The

test transmitter has the following properties:

1. Encoder decryption key = manufacturer’s code.

2. Serial number = any value.

3. Discrimination bits = lower 10 bits of the serial

number.

4. Synchronization counter value = any value

(synchronization information is ignored).

Because the synchronization counter value is ignored

in Test mode, any number of test transmitters can be

used, even if their synchronization counter values are

different.

4.6 Power Supply Supervisor

Reliable operation of the HCS515 requires that the

contents of the EEPROM memory be protected against

erroneous writes. To ensure that erroneous writes do

not occur after supply voltage “brown-out” conditions,

the use of a proper power supply supervisor device is

imperative (Figure 4-11 and Figure 9-2).

FIGURE 4-10: STAND-ALONE MODE LEARN/ERASE-ALL TIMING

FIGURE 4-11: TYPICAL STAND-ALONE APPLICATION CIRCUIT

DATA

Erase-All Activation

TREQ TLRN

CLK

BC D

Learn Activation

TERA

Successful

TLRN

OUTPUT0

RELAY SPST

VDD

LEARN

NPN

LED

10KΩ

VDD

GND

RST

MCP100-450

Voltage Supervisor

VDD

MCLR

VSS

RF_IN

S_CLK

S_DAT

10KΩ

VDD

10KΩ

from RF Receiver

HCS515

OUTPUT1

RELAY SPST

VDD

NPN

10KΩ

HCS515

5.0 DECODER PROGRAMMING

The memory is divided between system memory that

stores the transmitter information (read protected) and

user memory (read/write). Commands to access the

user memory are described in Sections 4.2.5 and

4.2.6.

The following information stored in system memory

needs to be programmed before the decoder can be

used:

• 64-bit manufacturer’s code

• Decoder configuration byte

Note 1: These memory locations are read pro-

tected and can only be written to using

the program command with the device

powered up.

2: The contents of the system memory is

encrypted by a unique 64-bit key that

is stored in the HCS515. To initialize

the system memory, the HCS515’s

program command must be used.

5.1 Configuration Byte

The decoder is configured during initialization by set-

ting the appropriate bits in the configuration byte. The

following table list the options:

5.1.1 LRN_MODE

LRN_MODE selects between two learning modes. With

LRN_MODE = 0, the Normal (serial number derived)

mode is selected; with LRN_MODE = 1, the Secure

(seed derived) mode is selected. See Section 6.0 for

more detail on learning modes.

5.1.2 REPEAT

The HCS515 can be configured to indicate repeated

transmissions. In a stand-alone configuration, repeated

transmissions must be disabled.

Bit Mnemonic Description

0LRN_MODE Learning mode selection

LRN_MODE = 0 – Normal

Learn

LRN_MODE = 1 – Secure

Learn

1 Not Used Reserved

2REPEAT Repeat Transmission enable

0 = Disable

1 = Enabled

3 Not Used Reserved

4 Not Used Reserved

5 Not Used Reserved

6 Not Used Reserved

7 Not Used Reserved

HCS515

5.2 Programming Waveform

The programming command consists of the following:

• Command Request Sequence (A to B)

• Command Byte (B to C)

• Configuration Byte (C to D)

• Manufacturer’s Code Eight Data Bytes (D to G)

• Activation and Acknowledge Sequence (G to H)

5.3 Programming Data String

A total of 80 bits are clocked into the decoder. The 8-bit

command byte is clocked in first, followed by the 8-bit

configuration byte and the 64-bit manufacturer’s code.

The data must be clocked in Least Significant bit (LSb)

first. The decoder will then encrypt the manufacturer’s

code using the decoder’s unique 64-bit EEPROM

encoder decryption key. After completion of the pro-

gramming EEPROM, the decoder will acknowledge by

taking the data line high (G to H). If the data line goes

high within 30 ms after the clock goes high, program-

ming also fails.

FIGURE 5-1: PROGRAMMING WAVEFORM

MSB

Command ByteSTART Command

CLKL

CLKH

LSB

START

DATA

Configuration Byte Least Significant Byte

DATA

REQ

RESP

CLK

Data

MSBLSB MSBLSB

HCS515

Data

DATA

Most Significant Byte

ACK

WTH

Acknowledge

WTL

LSB MSB

TABLE 5-1: PROGRAMMING COMMAND

Symbol Parameters Sugg. Value Min. Max. Units

TREQ Command request time d.o.d. 0.005 500 ms

TRESP Acknowledge time 100 10 1000 μs

TSTART Command request to first command bit 100 20 1000 μs

TCLKH Clock high time 100 20 1000 μs

TCLKL Clock low time 100 20 1000 μs

TDS Data hold time 50 14 1000 μs

TDATA Command last bit to data first bit 100 10 1000 μs

TACK Command acknowledge time d.o.d. 30 240 ms

TWTH Acknowledge respond time 100 20 1000 μs

TWTL Clock low to next command 100 10 — μs

Note: d.o.d. - depends on decoder status

These parameters are characterized but not tested

HCS515

6.0 KEY GENERATION

The HCS515 supports two learning schemes which are selected during the initialization of the system EEPROM. The

learning schemes are:

• Normal learn using the KEELOQ decryption algorithm

• Secure learn using the KEELOQ decryption algorithm

6.1 Normal (Serial Number derived) Learn using the Decryption Algorithm

This learning scheme uses the KEELOQ decryption algorithm and the 28-bit serial number of the transmitter to derive

the encoder decryption key. The 28-bit serial number is patched with predefined values as indicated below to form two

32-bit seeds.

SourceH = 60000000 00000000H + Serial Number | 28 bits

SourceL = 20000000 00000000H + Serial Number | 28 bits

Then, using the KEELOQ decryption algorithm and the manufacturer’s code the encoder decryption key is

derived as follows:

KeyH Upper 32 bits = F KEELOQ Decryption (SourceH) | 64-bit Manufacturer’s Code

KeyL Lower 32 bits = F KEELOQ Decryption (SourceL) | 64-bit Manufacturer’s Code

6.2 Secure (Seed Derived) Learn using the Decryption Algorithm

This scheme uses the secure seed transmitted by the encoder to derive the two input seeds. The decoder always uses

the lower 64 bits of the transmission to form a 60-bit seed. The upper 4 bits are always forced to zero.

For 32-bit seed encoders:

SourceH = Serial Number Lower 28 bits

SourceL = Seed 32 bits

For 48-bit seed encoders:

SourceH = Seed Upper 16 bits + Serial Number Upper 16 bits (with upper 4 bits set to zero) << 16

SourceL = Seed Lower 32 bits

For 60-bit seed encoders:

SourceH = Seed Upper 28 bits with upper 4 bits set to zero

SourceL = Seed Lower 32 bits

The KEELOQ decryption algorithm and the manufacturer’s code is used to derive the encoder decryption key as

follows:

KeyH Upper 32 bits = Decrypt (SourceH) 64-bit Manufacturer’s Code

KeyL Lower 32 bits = Decrypt (SourceL) 64-bit Manufacturer’s Code

HCS515

7.0 ENCODERS

7.1 Transmission Format (PWM)

The encoder transmission is made up of several parts

(Figure 7-1). Each transmission begins with a

preamble and a header, followed by the encrypted and

then the fixed data. The actual data is 66/69 bits, which

consist of 32 bits of encrypted data and 34/37 bits of

non-encrypted data. Each transmission is followed by

a guard period before another transmission can begin.

The code hopping portion provides up to four billion

changing code combinations and includes the button

status bits (based on which buttons were activated),

along with the synchronization counter value and some

discrimination bits. The non-code hopping portion is

comprised of the status bits, the function bits, and the

28-bit serial number. The encrypted and non-encrypted

combined sections increase the number of combina-

tions to 7.38 x 1019.

7.2 Code Word Organization

The HCS encoder transmits a 66/69-bit code word

when a button is pressed. The 66/69-bit word is con-

structed from a code hopping portion and a non-code

hopping portion (Figure 7-2).

The Encrypted Data is generated from four button bits,

two overflow counter bits, ten discrimination bits, and

the 16-bit synchronization counter value.

The Non-encrypted Data is made up from 2 status

bits, 4 function bits, and the 28/32-bit serial number.

FIGURE 7-1: TRANSMISSION FORMAT (PWM)

FIGURE 7-2: CODE WORD ORGANIZATION

LOGIC "1"

Guard

Time

50% Encrypted

Portion

Fixed Code

Portion

LOGIC "0"

Preamble

Header

10xTE

Repeat

(1-bit)

VLOW

(1-bit)

Button

Status

S2 S1 S0 S3

Serial Number

(28 bits)

Button

Status

S2 S1 S0 S3

OVR

(2 bits)

DISC

(10 bits)

Sync Counter

(16 bits)

Repeat

(1-bit)

VLOW

(1-bit)

Button

Status

1 1 1 1

Serial Number

(28 bits)

SEED

(32 bits)

34 bits of Fixed Portion 32 bits of Encrypted Portion

66 Data bits

Transmitted

LSb first.

LSb

MSb

MSb LSb

SEED replaces Encrypted Portion when all button inputs are activated at the same time.

HCS515

8.0 DEVELOPMENT SUPPORT

The PIC® microcontrollers and dsPIC® digital signal

controllers are supported with a full range of software

and hardware development tools:

• Integrated Development Environment

- MPLAB® IDE Software

• Compilers/Assemblers/Linkers

- MPLAB C Compiler for Various Device

Families

- HI-TECH C for Various Device Families

- MPASMTM Assembler

-MPLINK

TM Object Linker/

MPLIBTM Object Librarian

- MPLAB Assembler/Linker/Librarian for

Various Device Families

• Simulators

- MPLAB SIM Software Simulator

• Emulators

- MPLAB REAL ICE™ In-Circuit Emulator

• In-Circuit Debuggers

- MPLAB ICD 3

- PICkit™ 3 Debug Express

• Device Programmers

- PICkit™ 2 Programmer

- MPLAB PM3 Device Programmer

• Low-Cost Demonstration/Development Boards,

Evaluation Kits, and Starter Kits

8.1 MPLAB Integrated Development

Environment Software

The MPLAB IDE software brings an ease of software

development previously unseen in the 8/16/32-bit

microcontroller market. The MPLAB IDE is a Windows®

operating system-based application that contains:

• A single graphical interface to all debugging tools

- Simulator

- Programmer (sold separately)

- In-Circuit Emulator (sold separately)

- In-Circuit Debugger (sold separately)

• A full-featured editor with color-coded context

• A multiple project manager

• Customizable data windows with direct edit of

contents

• High-level source code debugging

• Mouse over variable inspection

• Drag and drop variables from source to watch

windows

• Extensive on-line help

• Integration of select third party tools, such as

IAR C Compilers

The MPLAB IDE allows you to:

• Edit your source files (either C or assembly)

• One-touch compile or assemble, and download to

emulator and simulator tools (automatically

updates all project information)

• Debug using:

- Source files (C or assembly)

- Mixed C and assembly

- Machine code

MPLAB IDE supports multiple debugging tools in a

single development paradigm, from the cost-effective

simulators, through low-cost in-circuit debuggers, to

full-featured emulators. This eliminates the learning

curve when upgrading to tools with increased flexibility

and power.

HCS515

8.2 MPLAB C Compilers for Various

Device Families

The MPLAB C Compiler code development systems

are complete ANSI C compilers for Microchip’s PIC18,

PIC24 and PIC32 families of microcontrollers and the

dsPIC30 and dsPIC33 families of digital signal control-

lers. These compilers provide powerful integration

capabilities, superior code optimization and ease of

use.

For easy source level debugging, the compilers provide

symbol information that is optimized to the MPLAB IDE

debugger.

8.3 HI-TECH C for Various Device

Families

The HI-TECH C Compiler code development systems

are complete ANSI C compilers for Microchip’s PIC

family of microcontrollers and the dsPIC family of digital

signal controllers. These compilers provide powerful

integration capabilities, omniscient code generation

and ease of use.

For easy source level debugging, the compilers provide

symbol information that is optimized to the MPLAB IDE

debugger.

The compilers include a macro assembler, linker, pre-

processor, and one-step driver, and can run on multiple

platforms.

8.4 MPASM Assembler

The MPASM Assembler is a full-featured, universal

macro assembler for PIC10/12/16/18 MCUs.

The MPASM Assembler generates relocatable object

files for the MPLINK Object Linker, Intel® standard HEX

files, MAP files to detail memory usage and symbol

reference, absolute LST files that contain source lines

and generated machine code and COFF files for

debugging.

The MPASM Assembler features include:

• Integration into MPLAB IDE projects

• User-defined macros to streamline

assembly code

• Conditional assembly for multi-purpose

source files

• Directives that allow complete control over the

assembly process

8.5 MPLINK Object Linker/

MPLIB Object Librarian

The MPLINK Object Linker combines relocatable

objects created by the MPASM Assembler and the

MPLAB C18 C Compiler. It can link relocatable objects

from precompiled libraries, using directives from a

linker script.

The MPLIB Object Librarian manages the creation and

modification of library files of precompiled code. When

a routine from a library is called from a source file, only

the modules that contain that routine will be linked in

with the application. This allows large libraries to be

used efficiently in many different applications.

The object linker/library features include:

• Efficient linking of single libraries instead of many

smaller files

• Enhanced code maintainability by grouping

related modules together

• Flexible creation of libraries with easy module

listing, replacement, deletion and extraction

8.6 MPLAB Assembler, Linker and

Librarian for Various Device

Families

MPLAB Assembler produces relocatable machine

code from symbolic assembly language for PIC24,

PIC32 and dsPIC devices. MPLAB C Compiler uses

the assembler to produce its object file. The assembler

generates relocatable object files that can then be

archived or linked with other relocatable object files and

archives to create an executable file. Notable features

of the assembler include:

• Support for the entire device instruction set

• Support for fixed-point and floating-point data

• Command line interface

• Rich directive set

• Flexible macro language

• MPLAB IDE compatibility

HCS515

8.7 MPLAB SIM Software Simulator

The MPLAB SIM Software Simulator allows code

development in a PC-hosted environment by simulat-

ing the PIC® MCUs and dsPIC® DSCs on an instruction

level. On any given instruction, the data areas can be

examined or modified and stimuli can be applied from

a comprehensive stimulus controller. Registers can be

logged to files for further run-time analysis. The trace

buffer and logic analyzer display extend the power of

the simulator to record and track program execution,

actions on I/O, most peripherals and internal registers.

The MPLAB SIM Software Simulator fully supports

symbolic debugging using the MPLAB C Compilers,

and the MPASM and MPLAB Assemblers. The soft-

ware simulator offers the flexibility to develop and

debug code outside of the hardware laboratory envi-

ronment, making it an excellent, economical software

development tool.

8.8 MPLAB REAL ICE In-Circuit

Emulator System

MPLAB REAL ICE In-Circuit Emulator System is

Microchip’s next generation high-speed emulator for

Microchip Flash DSC and MCU devices. It debugs and

programs PIC® Flash MCUs and dsPIC® Flash DSCs

with the easy-to-use, powerful graphical user interface of

the MPLAB Integrated Development Environment (IDE),

included with each kit.

The emulator is connected to the design engineer’s PC

using a high-speed USB 2.0 interface and is connected

to the target with either a connector compatible with in-

circuit debugger systems (RJ11) or with the new high-

speed, noise tolerant, Low-Voltage Differential Signal

(LVDS) interconnection (CAT5).

The emulator is field upgradable through future firmware

downloads in MPLAB IDE. In upcoming releases of

MPLAB IDE, new devices will be supported, and new

features will be added. MPLAB REAL ICE offers

significant advantages over competitive emulators

including low-cost, full-speed emulation, run-time

variable watches, trace analysis, complex breakpoints, a

ruggedized probe interface and long (up to three meters)

interconnection cables.

8.9 MPLAB ICD 3 In-Circuit Debugger

System

MPLAB ICD 3 In-Circuit Debugger System is Micro-

chip's most cost effective high-speed hardware

debugger/programmer for Microchip Flash Digital Sig-

nal Controller (DSC) and microcontroller (MCU)

devices. It debugs and programs PIC® Flash microcon-

trollers and dsPIC® DSCs with the powerful, yet easy-

to-use graphical user interface of MPLAB Integrated

Development Environment (IDE).

The MPLAB ICD 3 In-Circuit Debugger probe is con-

nected to the design engineer's PC using a high-speed

USB 2.0 interface and is connected to the target with a

connector compatible with the MPLAB ICD 2 or MPLAB

REAL ICE systems (RJ-11). MPLAB ICD 3 supports all

MPLAB ICD 2 headers.

8.10 PICkit 3 In-Circuit Debugger/

Programmer and

PICkit 3 Debug Express

The MPLAB PICkit 3 allows debugging and program-

ming of PIC® and dsPIC® Flash microcontrollers at a

most affordable price point using the powerful graphical

user interface of the MPLAB Integrated Development

Environment (IDE). The MPLAB PICkit 3 is connected

to the design engineer's PC using a full speed USB

interface and can be connected to the target via an

Microchip debug (RJ-11) connector (compatible with

MPLAB ICD 3 and MPLAB REAL ICE). The connector

uses two device I/O pins and the reset line to imple-

ment in-circuit debugging and In-Circuit Serial Pro-

gramming™.

The PICkit 3 Debug Express include the PICkit 3, demo

board and microcontroller, hookup cables and CDROM

with user’s guide, lessons, tutorial, compiler and

MPLAB IDE software.

HCS515

8.11 PICkit 2 Development

Programmer/Debugger and

PICkit 2 Debug Express

The PICkit™ 2 Development Programmer/Debugger is

a low-cost development tool with an easy to use inter-

face for programming and debugging Microchip’s Flash

families of microcontrollers. The full featured

Windows® programming interface supports baseline

(PIC10F, PIC12F5xx, PIC16F5xx), midrange

(PIC12F6xx, PIC16F), PIC18F, PIC24, dsPIC30,

dsPIC33, and PIC32 families of 8-bit, 16-bit, and 32-bit

microcontrollers, and many Microchip Serial EEPROM

products. With Microchip’s powerful MPLAB Integrated

Development Environment (IDE) the PICkit™ 2

enables in-circuit debugging on most PIC® microcon-

trollers. In-Circuit-Debugging runs, halts and single

steps the program while the PIC microcontroller is

embedded in the application. When halted at a break-

point, the file registers can be examined and modified.

The PICkit 2 Debug Express include the PICkit 2, demo

board and microcontroller, hookup cables and CDROM

with user’s guide, lessons, tutorial, compiler and

MPLAB IDE software.

8.12 MPLAB PM3 Device Programmer

The MPLAB PM3 Device Programmer is a universal,

CE compliant device programmer with programmable

voltage verification at VDDMIN and VDDMAX for

maximum reliability. It features a large LCD display

(128 x 64) for menus and error messages and a modu-

lar, detachable socket assembly to support various

package types. The ICSP™ cable assembly is included

as a standard item. In Stand-Alone mode, the MPLAB

PM3 Device Programmer can read, verify and program

PIC devices without a PC connection. It can also set

code protection in this mode. The MPLAB PM3

connects to the host PC via an RS-232 or USB cable.

The MPLAB PM3 has high-speed communications and

optimized algorithms for quick programming of large

memory devices and incorporates an MMC card for file

storage and data applications.

8.13 Demonstration/Development

Boards, Evaluation Kits, and

Starter Kits

A wide variety of demonstration, development and

evaluation boards for various PIC MCUs and dsPIC

DSCs allows quick application development on fully func-

tional systems. Most boards include prototyping areas for

adding custom circuitry and provide application firmware

and source code for examination and modification.

The boards support a variety of features, including LEDs,

temperature sensors, switches, speakers, RS-232

interfaces, LCD displays, potentiometers and additional

EEPROM memory.

The demonstration and development boards can be

used in teaching environments, for prototyping custom

circuits and for learning about various microcontroller

applications.

In addition to the PICDEM™ and dsPICDEM™ demon-

stration/development board series of circuits, Microchip

has a line of evaluation kits and demonstration software

for analog filter design, KEELOQ® security ICs, CAN,

IrDA®, PowerSmart battery management, SEEVAL®

evaluation system, Sigma-Delta ADC, flow rate

sensing, plus many more.

Also available are starter kits that contain everything

needed to experience the specified device. This usually

includes a single application and debug capability, all

on one board.

Check the Microchip web page (www.microchip.com)

for the complete list of demonstration, development

and evaluation kits.

HCS515

9.0 ELECTRICAL CHARACTERISTICS

Absolute Maximum Ratings†

Ambient temperature under bias............................................................................................................ -40°C to +125°C

Storage temperature ..............................................................................................................................-65 °C to +150°C

Voltage on any pin with respect to VSS (except VDD)......................................................................... -0.6V to VDD +0.6V

Voltage on VDD with respect to Vss ..................................................................................................................0 to +7.0V

Total power dissipation (Note) .............................................................................................................................700 mW

Maximum current out of VSS pin ...........................................................................................................................200 mA

Maximum current into VDD pin ..............................................................................................................................150 mA

Input clamp current, IIK (VI < 0 or VI > VDD) .........................................................................................................± 20 mA

Output clamp current, IOK (VO < 0 or VO >VDD) ..................................................................................................± 20 mA

Maximum output current sunk by any I/O pin..........................................................................................................25 mA

Maximum output current sourced by any I/O pin ....................................................................................................25 mA

Note: Power dissipation is calculated as follows: PDIS = VDD x {IDD - ∑ IOH} + ∑ {(VDD–VOH) x IOH} + ∑(VOL x IOL)

† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the

device. This is a stress rating only and functional operation of the device at those or any other condi-

tions above those indicated in the operation listings of this specification is not implied. Exposure to

maximum rating conditions for extended periods may affect device reliability.

HCS515

FIGURE 9-1: RESET WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP

TIMER TIMING

TABLE 9-1: DC CHARACTERISTICS

Standard Operating Conditions (unless otherwise stated)

Operating temperature

Commercial (C): 0°C ≤ T

A ≤ +70°C

Industrial (I): -40°C ≤ TA ≤ +85°C

Symbol Parameters Min. Typ.(†) Max. Units Conditions

VDD Supply voltage 4.5 — 5.5 V —

VPOR VDD start voltage to

ensure RESET

— Vss — V —

SVDD VDD rise rate to

ensure RESET

0.05* — — V/ms —

IDD Supply current — 1.8 2. mA FOSC = 4 MHz, VDD = 5.5V

IPD Power-Down Current — 10 50 μAVDD = 4.5V

VIL Input low voltage VSS —VMCLR = .2 VDD

VSS —0.8 VVDD between 4.5V and 5.5V

VIH Input high voltage 0.25 VDD + 0.8 — VDD VVDD between 4.5V and 5.5V

V Except MCLR = 0.80 VDD

VOL Output low voltage — — 0.6 V IOL = 8.5 mA, VDD = 4.5V

VOH Output high voltage VDD - 0.7 — — V IOH = -3 mA, VDD = 4.5V

† Data in “Typ” column is at 5.0V, 25°C unless otherwise stated. These parameters are for design guidance only

and are not tested.

* These parameters are characterized but not tested.

Note: Negative current is defined as coming out of the pin.

TABLE 9-2: AC CHARACTERISTICS

Standard Operating Conditions (unless otherwise specified):

Commercial (C): 0°C ≤ TA ≤ +70°C

Industrial (I): -40°C ≤ TA ≤ +85°C

Symbol Parameters Min. Typ. Max. Units Conditions

TETransmit elemental period 65 — 660 μs—

TOD Output delay 48 75 237 ms —

TMCLR MCLR low time 150 — — ns —

TOV Time output valid — 150 222 ms —

Note: These parameters are characterized but not tested.

VDD

MCLR

I/O Pins

Tov

TMCLR

HCS515

9.1 AC Electrical Characteristics

9.1.1 VALID TRANSMISSION NOTIFICATION

Standard Operating Conditions (unless otherwise specified)

Commercial (C): 0°C ≤TA ≤ +70°C

Industrial (I): -40°C ≤ TA ≤ +85°C

Symbol Parameters Min. Typ. Max. Units

TDHI Command request time 0.0050 — 500 ms

TCLA Micro request acknowledge time 0.0050 — 1 ms

TACK Decoder Acknowledge time — — 4 μs

TACT Start Command mode to

first command bit 20 — 1200 μs

TCLKH Clock high time 20 — 1000 μs

TCLKL Clock low time 20 — 1000 μs

FCLK Clock frequency 500 — 25000 Hz

TDS Data hold time 14 — 1000 μs

Note: These parameters are characterized but not tested.

9.1.2 COMMAND MODE ACTIVATION

Standard Operating Conditions (unless otherwise specified):

Commercial (C): 0°C ≤ TA ≤ +70°C

Industrial (I): -40°C ≤ TA ≤ +85°C

Symbol Parameters Min. Typ. Max. Units

TREQ Command request time 0.0050 — 500 ms

TRESP Microcontroller request

acknowledge time —— 1ms

TACK Decoder acknowledge time — — 4 μs

TSTART Start Command mode to first

command bit 20 — 1000 μs

TCLKH Clock high time 20 — 1000 μs

TCLKL Clock low time 20 — 1000 μs

FCLK Clock frequency 500 — 25000 Hz

TDS Data hold time 14 — — μs

TCMD Command validate time — — 10 μs

TADDR Address validate time — — 10 μs

TDATA Data validate time — — 10 μs

Note: These parameters are characterized but not tested.

9.1.3 READ FROM USER EEPROM COMMAND

Standard Operating Conditions (unless otherwise specified):

Commercial (C): 0°C ≤ TA ≤ +70°C

Industrial (I): -40°C ≤ TA ≤ +85°C

Symbol Parameters Min. Typ. Max. Units

TRD Decoder EEPROM read time 1000 — 2000 μs

Note: These parameters are characterized but not tested.

HCS515

9.1.4 WRITE TO USER EEPROM COMMAND

Standard Operating Conditions (unless otherwise specified):

Commercial (C): 0°C ≤ TA ≤ +70°C

Industrial (I): -40°C ≤ TA ≤ +85°C

Symbol Parameters Min. Typ. Max. Units

TWR Write command activation time 20 — 1000 μs

TACK EEPROM write acknowledge time — — 10 ms

TRESP Microcontroller acknowledge

response time 20 — 1000 μs

TACK2Decoder response

acknowledge time ——10μs

Note: These parameters are characterized but not tested.

9.1.5 ERASE ALL COMMAND

Standard Operating Conditions (unless otherwise specified):

Commercial (C): 0°C ≤ TA ≤ +70°C

Industrial (I): -40°C ≤ TA ≤ +85°C

Symbol Parameters Min. Typ. Max. Units

TERA Learn command activation time 20 — 1000 μs

TACK Decoder acknowledge time 20 — 210 ms

TRESP Microcontroller acknowledge

response time 20 — 1000 μs

TACK2Decoder data line low — — 10 μs

Note: These parameters are characterized but not tested.

9.1.6 ACTIVATE LEARN COMMAND IN MICRO MODE

Standard Operating Conditions (unless otherwise specified):

Commercial (C): 0°C ≤ TA ≤ +70 °C

Industrial (I): -40°C ≤ TA ≤ +85°C

Symbol Parameters Min. Typ. Max. Units

TLRN Learn command activation time 20 — 1000 μs

TACK Decoder acknowledge time — — 20 μs

TRESP Microcontroller acknowledge

response time 20 — 1000 μs

TACK2Decoder data line low — — 10 μs

Note: These parameters are characterized but not tested.

9.1.7 ACTIVATE LEARN COMMAND IN STAND-ALONE MODE

Standard Operating Conditions (unless otherwise specified):

Commercial (C): 0°C ≤ TA ≤ +70°C

Industrial (I): -40°C ≤ TA ≤ +85°C

Symbol Parameters Min. Typ. Max. Units

TREQ Command request time — — 100 ms

TLRN Learn command activation time — — 2 s

TERA Erase-all command activation time — — 6 s

Note: These parameters are characterized but not tested.

HCS515

FIGURE 9-2: TYPICAL MICROCONTROLLER INTERFACE CIRCUIT

9.1.8 LEARN STATUS STRING

Standard Operating Conditions (unless otherwise specified):

Commercial (C): 0°C ≤ TA ≤ +70°C

Industrial (I): -40°C ≤ TA ≤ +85°C

Symbol Parameters Min. Typ. Max. Units

TDHI Command request time — — 500 ms

TCLA Microcontroller command

request time 0.005 — 500 ms

TACT Decoder request acknowledge time — — 10 μs

TCLH Clock high hold time 1.2 ms

TCLL Clock low hold time 0.020 — 1.2 ms

TCLKH Clock high time 20 — 1000 μs

TCLKL Clock low time 20 — 1000 μs

FCLK Clock frequency 500 — 25000 Hz

TDS Data hold time — — 5 μs

Note: These parameters are characterized but not tested.

VDD

VIG

MCP100-450

Voltage Supervisor

VDD

MCLR

VSS

RF_IN

S_CLK

S_DAT

VDD

Receiver

Microcontroller

RST

In-circuit

Programming

Probe Pads

10K

HCS515

CLK

DAT

HCS515

10.0 PACKAGING INFORMATION

10.1 Package Marking Information

Legend: XX...X Customer specific information*

YY Year code (last 2 digits of calendar year)

WW Week code (week of January 1 is week ‘01’)

NNN Alphanumeric traceability code

Note: In the event the full Microchip part number cannot be marked on one line, it will

be carried over to the next line thus limiting the number of available characters

for customer specific information.

*Standard OTP marking consists of Microchip part number, year code, week code, and traceability code.

For OTP marking beyond this, certain price adders apply. Please check with your Microchip Sales Office.

For QTP devices, any special marking adders are included in QTP price.

XXXXXXXXXXXXXX

YYWWNNN

14-Lead PDIP Example

14-Lead SOIC Example

XXXXXXXXXXXXXX

0025NNN

XXXXXXXXXXXXXX

YYWWNNN

XXXXXXXXXXXXXX

0025NNN

HCS515

10.2 Package Details

/HDG3ODVWLF'XDO,Q/LQH3±PLO%RG\>3',3@

1RWHV

 3LQYLVXDOLQGH[IHDWXUHPD\YDU\EXWPXVWEHORFDWHGZLWKWKHKDWFKHGDUHD

 6LJQLILFDQW&KDUDFWHULVWLF

 'LPHQVLRQV'DQG(GRQRWLQFOXGHPROGIODVKRUSURWUXVLRQV0ROGIODVKRUSURWUXVLRQVVKDOOQRWH[FHHGSHUVLGH

 'LPHQVLRQLQJDQGWROHUDQFLQJSHU$60(<0

%6&%DVLF'LPHQVLRQ7KHRUHWLFDOO\H[DFWYDOXHVKRZQZLWKRXWWROHUDQFHV

1RWH )RUWKHPRVWFXUUHQWSDFNDJHGUDZLQJVSOHDVHVHHWKH0LFURFKLS3DFNDJLQJ6SHFLILFDWLRQORFDWHGDW

KWWSZZZPLFURFKLSFRPSDFNDJLQJ

8QLWV ,1&+(6

'LPHQVLRQ/LPLWV 0,1 120 0$;

1XPEHURI3LQV 1 

3LWFK H %6&

7RSWR6HDWLQJ3ODQH $ ± ± 

0ROGHG3DFNDJH7KLFNQHVV $   

%DVHWR6HDWLQJ3ODQH $  ± ±

6KRXOGHUWR6KRXOGHU:LGWK (   

0ROGHG3DFNDJH:LGWK (   

2YHUDOO/HQJWK '   

7LSWR6HDWLQJ3ODQH /   

/HDG7KLFNQHVV F   

8SSHU/HDG:LGWK E   

/RZHU/HDG:LGWK E   

2YHUDOO5RZ6SDFLQJ H% ± ± 

NOTE 1

123

A1 b1

0LFURFKLS 7HFKQRORJ\ 'UDZLQJ &%

HCS515

Note: For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging

HCS515

Note: For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging

HCS515

1RWH )RUWKHPRVWFXUUHQWSDFNDJHGUDZLQJVSOHDVHVHHWKH0LFURFKLS3DFNDJLQJ6SHFLILFDWLRQORFDWHGDW

KWWSZZZPLFURFKLSFRPSDFNDJLQJ

HCS515

APPENDIX A: ADDITIONAL

INFORMATION

Microchip’s Secure Data Products are covered by

some or all of the following:

Code hopping encoder patents issued in European

countries and U.S.A.

Secure learning patents issued in European countries,

U.S.A. and R.S.A.

REVISION HISTORY

Revision E (June 2011)

• Updated the following sections: Development Sup-

port, The Microchip Web Site, Reader Response

and HCS515 Product Identification System

• Added new section Appendix A

• Minor formatting and text changes were incorporated

throughout the document

HCS515

THE MICROCHIP WEB SITE

Microchip provides online support via our WWW site at

www.microchip.com. This web site is used as a means

to make files and information easily available to

customers. Accessible by using your favorite Internet

browser, the web site contains the following

information:

•Product Support – Data sheets and errata,

application notes and sample programs, design

resources, user’s guides and hardware support

documents, latest software releases and archived

software

•General Technical Support – Frequently Asked

Questions (FAQ), technical support requests,

online discussion groups, Microchip consultant

program member listing

•Business of Microchip – Product selector and

ordering guides, latest Microchip press releases,

listing of seminars and events, listings of

Microchip sales offices, distributors and factory

representatives

CUSTOMER CHANGE NOTIFICATION

SERVICE

Microchip’s customer notification service helps keep

customers current on Microchip products. Subscribers

will receive e-mail notification whenever there are

changes, updates, revisions or errata related to a

specified product family or development tool of interest.

To register, access the Microchip web site at

www.microchip.com. Under “Support”, click on

“Customer Change Notification” and follow the

registration instructions.

CUSTOMER SUPPORT

Users of Microchip products can receive assistance

through several channels:

• Distributor or Representative

• Local Sales Office

• Field Application Engineer (FAE)

• Technical Support

• Development Systems Information Line

Customers should contact their distributor,

representative or field application engineer (FAE) for

support. Local sales offices are also available to help

customers. A listing of sales offices and locations is

included in the back of this document.

Technical support is available through the web site

at: http://microchip.com/support

HCS515

READER RESPONSE

It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip

product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our

documentation can better serve you, please FAX your comments to the Technical Publications Manager at

(480) 792-4150.

Please list the following information, and use this outline to provide us with your comments about this document.

TO: Technical Publications Manager

RE: Reader Response

Total Pages Sent ________

From: Name

Company

Address

City / State / ZIP / Country

Telephone: (_______) _________ - _________

Application (optional):

Would you like a reply? Y N

Device: Literature Number:

Questions:

FAX: (______) _________ - _________

DS40183EHCS515

1. What are the best features of this document?

2. How does this document meet your hardware and software development needs?

3. Do you find the organization of this document easy to follow? If not, why?

4. What additions to the document do you think would enhance the structure and subject?

5. What deletions from the document could be made without affecting the overall usefulness?

6. Is there any incorrect or misleading information (what and where)?

7. How would you improve this document?

HCS515

HCS515 PRODUCT IDENTIFICATION SYSTEM

To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.

Package: P = Plastic DIP (300 mil Body), 14-lead

SL = Plastic SOIC (150 mil Body), 14-lead

Temperature Blank = 0°C to +70°C

Range: I = –40°C to +85°C

Device: HCS515 Code Hopping Decoder

HCS515T Code Hopping Decoder (Tape and Reel)

HCS515 —/P

Information contained in this publication regarding device

applications and the like is provided only for your convenience

and may be superseded by updates. It is your responsibility to

ensure that your application meets with your specifications.

MICROCHIP MAKES NO REPRESENTATIONS OR

WARRANTIES OF ANY KIND WHETHER EXPRESS OR

IMPLIED, WRITTEN OR ORAL, STATUTORY OR

OTHERWISE, RELATED TO THE INFORMATION,

INCLUDING BUT NOT LIMITED TO ITS CONDITION,

QUALITY, PERFORMANCE, MERCHANTABILITY OR

FITNESS FOR PURPOSE. Microchip disclaims all liability

arising from this information and its use. Use of Microchip

devices in life support and/or safety applications is entirely at

the buyer’s risk, and the buyer agrees to defend, indemnify and

hold harmless Microchip from any and all damages, claims,

suits, or expenses resulting from such use. No licenses are

conveyed, implicitly or otherwise, under any Microchip

intellectual property rights.

Trademarks

The Microchip name and logo, the Microchip logo, dsPIC,

KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro, PICSTART,

PIC32 logo, rfPIC and UNI/O are registered trademarks of

Microchip Technology Incorporated in the U.S.A. and other

countries.

FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor,

MXDEV, MXLAB, SEEVAL and The Embedded Control

Solutions Company are registered trademarks of Microchip

Technology Incorporated in the U.S.A.

Analog-for-the-Digital Age, Application Maestro, CodeGuard,

dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN,

ECONOMONITOR, FanSense, HI-TIDE, In-Circuit Serial

Programming, ICSP, Mindi, MiWi, MPASM, MPLAB Certified

logo, MPLIB, MPLINK, mTouch, Omniscient Code

Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit,

PICtail, REAL ICE, rfLAB, Select Mode, Total Endurance,

TSHARC, UniWinDriver, WiperLock and ZENA are

trademarks of Microchip Technology Incorporated in the

U.S.A. and other countries.

SQTP is a service mark of Microchip Technology Incorporated

in the U.S.A.

All other trademarks mentioned herein are property of their

respective companies.

Printed on recycled paper.

ISBN: 978-1-61341-227-5

Note the following details of the code protection feature on Microchip devices:

• Microchip products meet the specification contained in their particular Microchip Data Sheet.

• Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the

intended manner and under normal conditions.

• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our

knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data

Sheets. Most likely, the person doing so is engaged in theft of intellectual property.

• Microchip is willing to work with the customer who is concerned about the integrity of their code.

• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not

mean that we are guaranteeing the product as “unbreakable.”

Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our

products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts

allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.

Microchip received ISO/TS-16949:2002 certification for its worldwide

headquarters, design and wafer fabrication facilities in Chandler and

Tempe, Arizona; Gresham, Oregon and design centers in California

and India. The Company’s quality system processes and procedures

are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping

devices, Serial EEPROMs, microperipherals, nonvolatile memory and

analog products. In addition, Microchip’s quality system for the design

and manufacture of development systems is ISO 9001:2000 certified.

AMERICAS

Corporate Office

2355 West Chandler Blvd.

Chandler, AZ 85224-6199

Tel: 480-792-7200

Fax: 480-792-7277

Technical Support:

http://www.microchip.com/

support

Web Address:

www.microchip.com

Atlanta

Duluth, GA

Tel: 678-957-9614

Fax: 678-957-1455

Boston

Westborough, MA

Tel: 774-760-0087

Fax: 774-760-0088

Chicago

Itasca, IL

Tel: 630-285-0071

Fax: 630-285-0075

Cleveland

Independence, OH

Tel: 216-447-0464

Fax: 216-447-0643

Dallas

Addison, TX

Tel: 972-818-7423

Fax: 972-818-2924

Detroit

Farmington Hills, MI

Tel: 248-538-2250

Fax: 248-538-2260

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Tel: 317-773-8323

Fax: 317-773-5453

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Tel: 949-462-9523

Fax: 949-462-9608

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Santa Clara, CA

Tel: 408-961-6444

Fax: 408-961-6445

Toronto

Mississauga, Ontario,

Canada

Tel: 905-673-0699

Fax: 905-673-6509

ASIA/PACIFIC

Asia Pacific Office

Suites 3707-14, 37th Floor

Tower 6, The Gateway

Harbour City, Kowloon

Hong Kong

Tel: 852-2401-1200

Fax: 852-2401-3431

Australia - Sydney

Tel: 61-2-9868-6733

Fax: 61-2-9868-6755

China - Beijing

Tel: 86-10-8569-7000

Fax: 86-10-8528-2104

China - Chengdu

Tel: 86-28-8665-5511

Fax: 86-28-8665-7889

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Tel: 86-23-8980-9588

Fax: 86-23-8980-9500

China - Hangzhou

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Fax: 86-571-2819-3189

China - Hong Kong SAR

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Tel: 86-532-8502-7355

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Tel: 86-21-5407-5533

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Tel: 86-24-2334-2829

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Tel: 86-755-8203-2660

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Fax: 82-2-558-5932 or

82-2-558-5934

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Tel: 65-6334-8870

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Tel: 886-3-6578-300

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Taiwan - Kaohsiung

Tel: 886-7-213-7830

Fax: 886-7-330-9305

Taiwan - Taipei

Tel: 886-2-2500-6610

Fax: 886-2-2508-0102

Thailand - Bangkok

Tel: 66-2-694-1351

Fax: 66-2-694-1350

EUROPE

Austria - Wels

Tel: 43-7242-2244-39

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Tel: 34-91-708-08-90

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Tel: 44-118-921-5869

Fax: 44-118-921-5820

Worldwide Sales and Service

05/02/11