PIC1650-532/533 PLESSEY Semiconductors ADVANCE INFORMATION Advance information is issued to advise Customers of new additions to the Plessey Semiconductors range which, nevertheless, still have pre-production status. Details given may, therefore, change without notice although we would expect this performance data to be representative of full production status product in most cases. Please contact your local Plessey Semiconductors Sales Office for P1C1650-532/533 TELEVIEW CONTROL CHIP The Teleview control chip, PIC 1650-532/533 interfaces the user to the Teleview system and generally organises the operation of the system. Vss (NEGATIVE SUPPLY) [J+ Vv 40] vxx (Positive supPLy) It is available in several versions each providing alternative AD ADDRESS INPUT/QUTPUT [] 2 3ef) vop user inputs and operating features. Customised versions can Al AQDRESS INPUT/OUTPUT []3 33 - be provided if required. The details of the various versions a2 abbas mpuT/ouTPuT [] 4 a7P) ESET are shown in this datasheet. Test [Js asf asc A3 ADORESS INPUT/OUTPUT [Je 35%] CLOCK OUTPUT FEATURES A4 ADDRESS INPUT/OUTPUT []7 34[) D7 OTA INPUT/OUTPUT AS ADDRESS INPUT/OUTPUT (]6 33]]) 06 DATA INPUT/OUTPUT a Interfaces User to Teleview System AB ADDRESS INPUT/OUTPUT []9 327.) DS DATA INPUT/OUTPUT B initialises Teleview System AT ADDRESS INPUT/OUTPUT [10 Fic ese 3t[) 04 DATA INPUT/OUTPUT M@ = = PIC1650-532 ASCII or Binary (IR Remote), Initialises AR ADDRESS INPUT/OUTPUT []1 30) D3 DATA INPUT/oUTPUT to Picture Mode AS ADDRESS INPUT/QUTPUT [] 12 20] 02 DATA INPUT/oUTeUT HM = PIC1650A-533 ASCII or IR Remote, Viewdata only, READ/WRITE OUTPUT [13 2e[.] 01 DATA INPUT/OUTPUT Local Programming of EAROM $80 STORE SELECT OUTPUT [14 27) Bo pata iNPUT/aUTeUT SS1 STORE SELECT OUTPUT q 15 26 al KB? KEYBOARD INTERFACE $S2 STORE SELECT OUTPUT q 16 25 0 KBB KEYBOARD INTERFACE TS1 TIMESLOT INPUT []17 24] KBS KEYBOARD INTERFACE T$2 TIMESLOT INPUT []18 231) KB4 KEYBOARD INTERFACE BO KEYBOARC) INTERFACE qd 19 22) iy KB3 KEYBOARD INTERFACE KB1 KEYBOARD INTERFACE q 20 210) KB2 KEYBOARD INTERFACE PIN FUNCTIONS DP40 Fig.1 Pin connections - top view Pin Number Name Function 1 Vss Negative supply (Ground) 2-12 A0-AQ Address Input/Outputs which are connected to the Teleview Address Bus 5 Test Test pin - connect to Vss 13 Read/Write [Control output connected to the Teleview Store RW input 14-16 S$S0-SS2 Store Select outputs 17,18 TS1,TS2 Time Slot Inputs from Video Generator 19-26 KBO-KB7 Keyboard Interface, may be Inputs, Outputs or Inputs/Outputs depending on the version 27-34 DO-D7 Data Inputs/Outputs which are connected to the Teleview Data Bus 35 Clock Output! Not used except to check the Clock frequency (output frequency fc/4) 36 Oscillator Oscillator resistor and capacitor connected to this pin 37 Reset Master reset input which must be kept at ground potential until the VDD power is within specification 38 Not used 39 veox ai : 40 VXX Positive power supplies +5V Nom. 99PIC1650-532/533 ABSOLUTE MAXIMUM RATINGS Voltage on any pin with respect to Vsspin............. Ambient operating temperature range Storage temperature range 0.3V to +15V 0C to +70C ~55C to +150C Exceeding these ratings could cause permanent damage. Functional operation is not gudranteed under these conditions. Operating ranges are specified below. ELECTRICAL CHARACTERISTICS (See PIC1650A Date Sheet for. full specification}. Standard conditions (unless otherwise stated) vSS = OV VDD = +5V +10% VXX = +5V+10% Felock = 1MHz Ta = 0C to +70C Characteristic Min Typ Max Units Conditions Clock Frequency 08 1.0 MHz Input Low Voltage 0.2 0.8 Vv Input High Voltage 24 Vv Input High Voltage (Reset) Vdd-1 Vv tnput Low Current 200 1600 vA | VIL =O04V input High Current t00 MA | VIH=2.4V Input Leakage Current (Reset) 10 10 BLA Output Low Voltage 0.4 Vv 1(OL=1.6mA Output High Voltage 24 Vv 1OH = -100KA Supply Current 60 mA | IDD+IXX CONTROL DESCRIPTION The PIC1650 The Control device performs the following essential functions. 1. Interfaces a user input via a keyboard or probably a remote contro! to the Teleview system. 2. Provides a contro! of the data interchange between the Data Acquisition and Video Generator chips of the Teleview system. 3. Provides the means to access the data and address highways for writing to or reading from the various pages of Store. 4. May access the data and address highways for any other purpose to be defined. This may include other peripherals such as magnetic storage, hard copy devices etc. The Control device requires 32 I/O's broken down into 3 sections. Eight bits for keyboard interface Eight bits for connection to data highways Sixteen bits for connection to address highway, including the read/write, Store select and Time Slot data. The timing of a Control device is strictly limited by the fact that it must perform its functions within specific times, defined by the Time Slot data from the Video Generator (see MR9735 Datasheet), The Data and Address highways are shared by the other devices and the Contro! must not use the highways at the wrong time. 100 The Teleview system uses the PIC1650, single chip microcomputer, as the Control device. It is a standard part that is programmed as outlined in Appendices 1 and 2. The Program The Program is not totally fixed. It consists of basic processing sections but there are two versions with variations in initialisation keyboard types and features. The keyboard versions and features are described although it must be remembered that not all features may be included with any keyboard configuration. The program initially includes operating facilities for both Teletext and Viewdata but clearly these functions may be separated in order to provide program space for extra facilities. Initialisation. At power on the initialisation routine must be entered to set up the system to its initial state. As well as internal latches, registers and so on the DA, VG and Stores must be initialised. The following initiatising routines will be performed: DA. The DA will be sent codes to simulate the key depression. P-OOT---- {although the program may be modified to send any page and time digits). tt will be told Store number 7 {6 in binary). Video Generator. The VG will be sent codes to set ail control bits to zero, to simulate P key pressed, Picture Mode, not mix mode, not box clock, display store 6 (binary) and cursor Off. In addition it will be cycled round all 8 Stores with the Erase bit set (in Viewdata to erase all rows).In Viewdata only applications the Picture/Text key may be simulated to set the system into the Text mode and black and white only applications may be initialised into mix mode. Stores. The Stores will be fully erased by the Video Generator and then each will have up to 10 characters inserted (nominally in the middie of the screen), to provide some indication of an empty Store. Teleview is currently used in both versions, colour or height indicating keyboard versions or Viewdata (in the -533 version) respectively. VO Lines Al! (/O lines must always be put into the non- active state (output devices off, high level) whenever the Control is not actually using them. Synchronisation The Control is synchronised to the rest of the Teleview system by the Time Slot bits, TS1 and TS2. Whenever a job is finished the I/O lines will be made free and the TS bits examined. The Control will then remain idle until a change occurs in the TS status. At the change they will be decoded into 1 of four time slots and the appropriate subroutine performed. Processing must be ensured to take less than the minimum time for that time slot and at the end of processing must make !/Os free and again go idle. Teletext Lines Time Slot (TS10) This will normally be 16 TV lines long (1024us) but may be a minimum of two (128s). The Control has nothing to do in this time slot because the Teleview Data Acquisition must have use of the highways and there may not be much time available. However, it can use the time to update internal memory at frame rate (20ms) if required. Display Time Slot (TS00) 240 lines long (15.36ms) Control may not use the highways at this time (except perhaps around the line flyback) since the Video Generator will be reading and displaying the contents of Store. The Control will normally process the keyboard and decide on the action to be taken according to which key has been pressed (see KEYBOARD DESCRIPTION). Data Interchange Time Stot (TS11) 24 lines long (1536s) The Control device takes contro! of the Data and Address highways during this time slot to control the interchange of data around the system. it uses the Address highway to signal to the other devices, as described later, and to avoid the Store from interfering with the data highway the Read/Write line is set to Write. The following functions are performed: 1. If initialising, data is sent to the DA to simulate the depression of keys P-OOT----, Data is sent to Video Generator, the Store number is incremented and the first two words primed for sending again next time. The first two words are the ones containing the Store number and Erase bit. 2. In both Teletext and Viewdata the Control first gets data from the DA. The four words are read into the Control as described later and stored if strobe set. The PBR bit and the Strobe bit are checked in word 2 to decide if a page is being received and a latch is set if appropriate. 3. After getting data from DA data may be sent to the DA. In Viewdata only the Store Select number is sent. In Teletext the content of the data word that was set up during the keyboard routine is examined and, if appropriate, data is sent. !f P or T latches are set, indicating those keys had been pressed, the appropriate code is sent to DA together with don't care digits to clear out the DA's digit store. If P was pressed all page and time digits are cleared while if T pressed only the 4 time digits. P is only sent to DA if itis not currently receiving a page, i.e. between pages, so part pages are not stored, unless P had been pressed twice. If Storing Rotating pages and a page has been received a new Store number is sent to the DA. PIC1650-532/533 4. After dealing with the DA signalling data may be sent to the Video Generator. a. Firstly control bits are modified by the Control if appropriate and these include setting the Erase bit for First appearance or clearing all control bits and setting Erase bit if rolling. b. The seven control to Video data words are examined in turn and if appropriate are sent to the Video Generator. 5. After processing the DA and VG if the system is in Viewdata data may be sent to the Modem and the cursor location obtained from the DA (as described later). Spare Time Slot (TSO1), 24 lines long (1536s) This slot is used by the Control to process the Store. Keyed digits in Teletext are inserted in the Store for display and in Viewdata the Cursor must be inserted. The Stores may also be initialised. The functions performed are as follows: 1. Initialisation. At power on or after the Reset command an initialisation routine is performed. The Stores will be erased by the Video Generator in turn and after each one has been erased characters may be written to Store by the Control. Up to 10 characters may be inserted, normally in the centre of the screen (starting at character number 415). Initially Teleview is presented by the program may be changed for any characters as required (Double Height text is used in -533 version). 2. Normal processing begins by putting the Store Select code out to the highway. If in Teletext the various key flags are then examined in turn: a. PKey. If P kev has been pressed the first 8characters in the Store are cleared. b. SS. If Store Select key has been pressed the first 8 characters are cleared and the current Store number inserted (as in d.). c. TKey. If T key has been pressed any non entered page digits are filled with -s. Character T is put into 4th position and 5-8 filled with -'s. d. If a digit is ready for storing the appropriate address is extracted, the character written to Store and the address incremented. 3. When a character is written to Store the correct timing must be observed, as outlined below: Address is Output Write bit set Data Output Write bit cleared Data cleared (to high levels) Address may be changed. spaoop 4. If in Viewdata the location defined by the address received from the DA must have the cursor bit set. In this case the character at that location is read, the cursor bit is set and that location rewritten. KEYBOARD INPUTS The keyboard inputs are 8 parallel bits where the MSB is used to indicate the signalling mode employed. Two signalling modes are available: ASCII, which uses return-to-zero signalling, and Binary, which also performs an acknowledgement routine. Any other keyboard input may be processed, however, if the limitations of an 8-bit input and a sample rate of once per 20ms are noted. 101PIC1650-532/533 ASCII Mode ASCII mode key meanings are given in Table 1. Viewdata ASCII Codes Key Operation ASCIl Code, Hex Meaning CONTROL A 01 Picture/Text CONTROL B 02 Clear CONTROL C 03 Reveal/Conceal CONTROL D 04 Store Select CONTROL F 06 Mix All other codes Transmitted to line except digit following Store Select Teletext ASCII Codes Key Operation ASCIt Code, Hex Meaning 0, --, 9 30, -----, 39 0, -----, 9 3A Page ; 3B Time CONTROL A 01 Picture/Text CONTROL B 02 Update CONTROL C 03 Reveal/Conceal CONTROL D 04 Store Select CONTROL F 06 Mix < 3c Box Clock = 3D Hold/Store rotating pages > 3E Roll Headers 2? 3F Half page expansion Table 1 ASCII key codes Binary Mode The Binary (Local or Remote) mode codes are detailed in the Appendices at the end of this Datasheet. Keyboard Actions After the keyboard processing routine has decided on which key has been pressed the actions are as follows: Digits 0-9. If following the Store Select key and digits 1-8 the Store number is being updated. The Store Select flag is cleared, blank digit made ready to put into Store and the Video word (Control word to Video Generator - see Data Highways, Signalling) loaded. SSO may be read as Reset and SS9 as Roll Headers or Hold. A normal digit in Teletext is prepared for loading in Store and for sending to the DA, a digit counter keeping a check of which digit has been entered. More than 3 page digits or 4 time digits are not allowed and are ignored. A normal digit in Viewdata is made ready for sending out to the Modem. P Key. fin Viewdata mode this is treated as and is made ready for sending out (not in ASCII version since there are individual keys for the two functions). Otherwise ail previously selected modes are cleared; digit counter reset; first appearance flag set; P is loaded into the Video word. If the P key has been pressed a second time before being actioned a P twice flag is set for resetting the DA, via Data Highway signalling. T Key. fin Viewdata mode, this is treated as #' for sending 102 to the UAR/T (not in ASCII version). If in Teletext mode and the 3rd page digit has not been entered the Roll mode is set; Store Select is cleared; T prepared for loading to Store; T key flag set; T loaded into DA word (Control word to DA - see Data Highway, Signalling). Picture/Text. The mix bit is cleared and the P/T bit 6 set in the Video words. Update/Clear. If in Viewdata then set the Video word. If in Teletext and the page digits have not been entered, then treat as a dont care otherwise load the Video word. Reveal/Conceal. word, The appropriate bit is set in the Video Store Select. The Store Select flag is set. If in Teletext, the Display Store number is prepared for loading to Store. If Rolling Pages then stop them by loading Page Tens digit 14 to the DA. Simulate P key to Video Generator. Roll Headers (also SS9). Prepare to send P to DA. Mix. The Mix bit is toggled and prepared for sending to the Video Generator. SP bit is set in Video word. Box Clock. The BC bit is toggled and prepared for sending to the Video Generator. Don't Care (i.e.U/C Key) Prepares for loading - into Store and increments digit counter. If in place of the third page digit, T is prepared for sending to the DA and the Roll mode is set.Reset (SSO). The initialisation routine is entered in order to erase all Stores and start again. Hold (also Store Rotating Pages). Hold mode is toggled. if entering hold mode store number incremented and prepared for sending to DA. If ending the Hold mode, the current Store number is prepared for sending to the DA. Rounding Off. The appropriate key will cause control bits C12, 13 and 14 to be set so that character rounding may be switched off. Half Page Expansion. in the Video word. ADDRESS HIGHWAY Description This key will set the appropriate code This highway provides addressing for the various Stores (together with the read/(write) signal) and it will also be used to address the various building blocks of the Teleview system. The 16 bits of highway are made up, starting at the least significant end, from the 10 bits of Address followed by the Read/(write) signal, the three Store Select bits and two Time Slot bits. To avoid stored data from getting onto the data highway PIC 1650-532/533 when nothing is being addressed the highway free state will address an unused part of the store and thus be all 1's. Normal logic levels are therefore used. The Store will also be put into the write mode. SIGNALLING During the Data Interchange Time Slot (TS11) the Control device uses the Address Highway to signal which devices in the system should write to/read from the Data Highway. These codes are given in Table 2. External signalling to blocks of the Teleview system must comply with this Addressing procedure, and should only take control on determining the Highway free status, and Time Slot data. It can be seen that the addresses used for signalling Purposes, 1111XXXXXxX, will address unused parts of the Store since character addresses go from 0000000000 to 1110111111. In addition to the above the Control may request the next character position from the DA in order to insert the cursor. The request is made by signalling all zero on the Store Select highway during the data interchange time siot when the DA will respond with the appropriate address. The data highway cannot be used at this time since the character currently in that location in Store zero will be read onto the display highway. Store Read/ Select (write) 10 Bit Address s s s A a a a a a a a a a DA send 1 1 1 0 1 1 1 1 x x xX x 1 0 DA receive 1 1 1 0 1 1 1 1 x Xx xX x 0 1 Video receive 1 1 1 0 1 1 1 1 x xX 0 1 x x Modem receive 1 1 1 0 1 1 1 1 x 0 x xX x x Special interface receive 1 1 1 0 1 1 1 1 0 xX xX xX x x Table 2 Address highway signalling DATA HIGHWAY Description The Data Highway is &-bit parallel, and is used to send display data (characters and display control characters) to Store as well as System contro! information between the various blocks. So that the Highway free state should look like all zero's, inverse logic is employed. Signalling Basic character data only requires 7 bits so the data in and out of the Store uses the seven least significant bits as the character code. The eighth (most significant) bit is reserved for the Cursor. Interunit signalling uses the same 8 bit data highway and uses only the least signficant seven bits for the data. However, since signalling between the main components in the system is asynchronous read when the strobe is a logic 1 (zero volts). Because of the asynchronous nature of the Control chipall signals to it are acknowledged. When the Control has satisfactorily read a piece of data it will force all 1s to the highway and then release back to all Os ready for the next signal. Table 3 shows the signalling by the Control intended for the Data Acquisition Block of the Teleview system. Note that Sss is a Store Select number (Binary) from 000 to 111. Codes 110, 101 and 011 may be used to address 3 stores (or less) without decoding (i.e. one per bit) so for this reason the Controi will initialise the system to code 110 (Binary 6, Store 7). Code Dddd refers to a Digit Key value which is from 0, -, 9, 15 although any value can be sent. 103PIC1650-532/533 Code Meaning Comments 0000 0000 | Highway free 1000 Dddd | Magazine Number Range from 0 7 (Binary) Digit 15 recog- 1001 Dddd | Page Number Tens nised by MR9710 1010 Dddd [| Page Number Units as a Don't Care 1011 OSss_j Store Select 1011 10Kk | Key Pressed Kk = 00 is Page, 01 is Time, Kk = 10 or 11 both spare 1011 1100 | Spare Code 1011 1101 | Spare Code 1011 1110 | Spare Code 1014 1111 Dummy Code 1100 Dddd | Time, Hours Tens Range from 0 3 Digit 15 1101 Dddd | Time, Hours Units recognised 1110 Dddd | Time, Minutes Tens Range from 0 7 by MR9710 as 1111 Dddd | Time, Minutes Units a Don't Care NOTES 1. Active low signalling. 2. Most significant bit is a Strobe. The Control will also request information from the DA (by the appropriate Address on the Address Highway) by use of the Data Highway as shown in Table 4. Having obtained this information from the Data Acquisition Block, and obtained any display requests from the user (via the keyboard Table 3 Data highway signalling ; Control to DA interface) the Control will send information to the Video Generator to update its Control and Display latches. After receiving the appropriate address on the Address Highway the Video Generator can now be signalled to on the Data Highway as shown in Table 5 and 6. Code Meaning Comments s Control Word 1 Sent first, always sent. T is Teletext bit, 1 = Teletext. Sss = Store Select number that DA is currently using. For Teletext, further codes are: Sent only when a valid Header is received by the DA. PRB set when a page is being received. 1001 PRB C4 C6 C5 | Control Word 2 1010 C10 cg ce C7 | Control Word 3 1011 C14 C13 Ci2 C11 | Control Word 4 C4 to C14 are the Teletext control bits. Further codes for Viewdata are: Sent only when a Contro! Character is 1001 x F QO 0 | Control Word 2 received by the DA. F is sent when the 1010 b7 0 b6 b5 | Control Word 3 Form Feed character is detected. 1011 b4 b3 b2 b1_ | Control Word 4 bt - b7 are the seven bits comprising the Viewdata character. NOTES 1, Sent means that the Strobe bit (ie. MSB) is set. 2. Signals acknowledged by control forcing all 1's. Table 4 Data highway signalling : DA to Control Code Meaning Comments 1000 T $s s j Control Word 1 Sss = Store being written to. 1001 * * * * | Control Word 2 * Codes are as defined in Table 4, for 1010 * * * | Contro! Word 3 Viewdata and Teletext as shown. Teletext . . : it 1011 . ; : | Control Word 4 control bits or Viewdata character bits wi be as received by the Control. 1100 SP D d | SP = Set P/T to Picture Ddd = Store being displayed from. 1101 KY P ky ky | Key Data See also Table 6. P = P key pressed. 1110 Xx BH M BC | BH = Box Header. Latches set/reset by appropriate bit. M = Mix. BC = Box Clock. 104 Table 5 Data highway signalling; Control to Video GeneratorPIC1650-532/533 KY ky ky Meaning Comments 0 0 1 Picture/Text key pressed 0 1 0 Reveai/Conceal key pressed A a te de. 0 7 7 Half Page key pressed Latches toggled by the appropriate co 1 0 0 Update/Ciear key pressed 1 0 1 Rounding and Flashing OFF |Reset by P key/New Viewdata Page or Store Select. 1 1 1 Hold Not used by MR9735 Table 6 Key data control word interpretation Finally, the Control will also signal to a Modem in the same manner. In this case however, it is active high signalling with the MSB an active low strobe (i.e. inverse case). The seven bit code will be intended for the modem; Control signals required by a UAR/T will be generated by the Teleview DA unit. Note that the DA will respond to the address modem receive and, together with the strobe, will enable the UAR/T to read the Highway. APPLICATION NOTES Figs. 2, 3 and 4 show circuit diagrams of three options for signalling via the keyboard interface. Those of Figs. 2 and 3 use the ASCII return-to-zero mode for remote or local applications. One point to note is that the extra logic based around a NAND latch provides an enable/disable feature for the remote option: a transmitted 11111 code from the SL490 allows subsequent codes to communicate with the PIC1650- 532. A transmitted 11011 code disables communication and thus allows bits 1 to 6 (KBO to KB5) to be used again for signatling to other devices i.e. the PIC 1650-532 will ignore all subsequent codes since KB6 (pin 25) is held iow as a result of the disable code. The enable/disable codes can be changed by alternating the connections to the 41/P AND gate driving the NAND latch, or omitted altogether by connecting KB6 to KB5 in common with the drive to KB5. To signal in remote mode (and thereby avoid the condition referred to in Note 2 above) simple extra logic as shown in Fig.4 can be employed. The KB7 pin is pulsed low by the PIC 1650-532 operation every 20ms, and this is used to drive a simple NAND latch which forms an acknowledgement-type function with the ML924 outputs. Note that omitting the enable/disable feature is still possible as before, simplifying the AND gate driving KBS and KB6 to a 2-input gate. Similar logic can of course be employed for a local keypad using Remote mode. 105PIC1650-532/533 ALL 22k a7 KBS ALL 2N3908 KBO KB1 KBO-KB7 > INPUT TO ALL 4700 PIC1650-532 KB2 NB ASCII MODE RETURN TO ZERO ALL 4700 SIGNALLING WITH MSB =0 Fig. 2 Local keypad using ASCH mode signalling 106PIC1650-532/533 ca 150y 10 TR2 60437 PPS oe 2xCayvs9 oe 1x CQxa7 Transmitter +5V PIC 1650-532 on Fob ow CoS LOGIC TOR 1 OUTPUT TYPE SELECT, SEE TABLE 1 ALL 2700 ENABLE/ DISABLE (x2 INPUT) LOGIC GF REQUIRED) Receiver 107PIC1650-532/533 C4 150y 10 TR2 8D437 PPS xcaves OR Ge 1x COKa7 Transmitter +5 PIC1650-532 (3x2 INPUT) 40st Receiver Fig.4 Remote keypad using Remote mode signalling 108PIC1650-532/533 PIC 1650-532 APPENDIX 1 This version interfaces either with an ASCI! return to zero keyboard or from remote control receiver data. INPUT (a) ASCII Return to zero (b) Binary Return to zero (from local keyboard or remote control) POWER UP MODE Picture POWER UP DISPLAY (a) ASCII Teleview Cyan (b) Binary Teleview Yellow POWER UP PAGE XOO in Store 7 KEYBOARD INTERFACE KBO pin 19 LSB Input KB1 pin 20 LSB Input KB2 pin 21 LSB Input KB3 pin 22 LSB input KB4 pin 23 LSB Input KB5 pin 24 LSB Input KB6 pin 25 MSB Input KB7 pin 26 ASCII/Local Binary Input or Remote Acknowledge KEYBOARD CODES (a) ASCII Standard 7 bit ASCII (These codes are only acted upon in Viewdata Mode) (b) Binary (Loca! or Remote) Binary Code Key Meaning MSB- LSB 1100000 Picture/Text 1100001 Mix 1100010 Half Page Expansion 1100011 Store Select 1100100 7 1100101 8 1100110 9 1100111 Box Clock 1101000 4 1101001 5 1101010 6 1101011 Hold (Store Rotating Pages) (Release Line) 1101100 1 1101101 2 1101110 3 1101111 Reveal/Conceal 1110000 Page (or * in Viewdata) 1110001 0 1110010 Time (or #in Viewdata) 1110011 Update/Clear 1110100 Rounding + Flash Off 1110101 Cursor ON 1110110 Cursor OFF 1110111 Roli Headers 109PIC 1650-532/533 PIC1650A-533 APPENDIX 2 This version interfaces either with an ASCU, return to zero keyboard or with a remote control receiver and as such may replace pattern 532. It provides control of Viewdata functions only together with Local Programming of Telephone numbers via PIC1650Z-536. INPUT ASCII return to zero or binary return to zero from local keyboard or direct connection to remote receiver. POWER UP MODE Text, Cursor off POWER UP DISPLAY Double height Teleview in yellow on blue POWER UP STORE Store number 1 (binary 000) KEYBOARD INTERFACE KBO pin 19 LSB Input KB1 pin 20 LSB Input KB2 pin 21 LSB Input KB3 pin 22 LSB Input KB4 pin 23 LSB Input KB5 pin 24 LSB Input KB6 pin 25 MSB Input KB7 pin 26 ASCII/Local Binary Input or Remote Acknowledge KEYBOARD CODES (a) ASCH Full 7 bit ASCII set (b) Binary {local or remote) Binary Code Key Meaning 1100000 Picture/Text 1100001 Print 1100010 Half Page Expansion 1100011 Store Select 1100100 7 1100101 8 1100110 9 1100111 (Not Used) 1101000 4 1101001 5 1101010 6 1101011 Hold/Disconnect Line 1101100 1 1101101 2 1101110 3 1101111 Reveal/Conceal 1110000 Star 1110001 0 1110010 Square 1110011 Clear (Inhibit Display) 1110100 Rounding & Flashing Off 1110101 Cursor On 1110110 Cursor Off 4110111 Reset Notes 1 and 2 as for pattern 532. 110OPERATION (a) ASCII codes transmitted directly to tine via UAR/T and MODEM. If 536 autodialler fitted, square and digits 1-4 will enable dialling. (b) Picture/Text. Switches display alternately between picture and text. If 536 autodialler fitted this key will drop the telephone connection. (c) Print. Aiternately puts system into MIX mode and back to normal. Mix mode enables monochrome video to be generated and removes coloured backgrounds. When entering mix mode character rounding and flashing are inhibited until new page received (only for MR9735). (d) Store/Select. Followed by digits 1-8 will select one of eight possible Stores for display. If 536 autodialler fitted and system in link-back' mode then Local Programming of telephone numbers may be enabled by selecting zero. SSO will clear screen and digits 1-4 may be pressed to enable the programming of the appropriate telephone number. The number is entered using digits 0-9 (0 displayed as :) star for access pause (displayed as ;) and square as formatter and space filler (displayed as 7) to complete all 16 digits. SSO followed by Reveal will display all the telephone numbers on the screen. (e) Hold. If the 536 autodialler is fitted this key will drop the telephone line. (f) Reveal/Conceat. Will alternately reveal and conceal characters. Initialised to conceal state for new page or new Store. (g) Clear. Clears the screen of all text. Display restored by second depression of the key and by reception of a new page. (h) Rounding and Flashing Off. Character rounding and flashing may be inhibited in MR9735 until a new page is received. (i) Cursor ON/OFF. The cursor may be locally controlled by these codes. (j) Reset. Simulate the power-on reset. All stores are cleared and initialised to Teleview. PIC1650-532/533 Notes: During initialisation the P1C1650-532/533 decides whether an ASCII keyboard or a remote control receiver is being used. If all Keyboard Interface inputs are low an ASCII keyboard is assumed. 1.(a) ASCII Mode Return to zero signailing is employed, the KB7 input being used to switch from full ASCII to local Binary. With KB7 equal to 1 the other 7 bits are read as standard ASCII. (Note this input must be pulsed with the other bits). With KB7 equal to 0 the other 7 bits are read as binary with meanings detailed above. (b) Remote Mode In this case the same binary codes are used but an acknowledgement routine is performed by the PIC1650- 532/533. The connections between the P1C1650-532/533 and a remote control receiver are made as follows: PIC1650-532 REMOTE CONTROL WORD KBO pin 19 LSB CODE BITA KB1 pin 20 CODE BIT B KB2 pin 21 CODE BIT C KB3 pin 22 CODE BIT D KB4 pin 23 CODE BIT E KB5 pin 24 CODE BIT F KB6 pin 2 MSB CODE BIT G KB7 pin 26 ACKNOWLEDGE SIGNAL 2. The codes should be valid for a minimum of 20msecs. In the ASCII mode if two key operation SSO is used the Second code (0) should only be valid for a maximum of 120ms to avoid changing keyboard modes (see Application Notes). 3. The double key operations are recognised: (a) Store Select 9 is equivalent to Roll Headers. (b) Store Select 0 is equivalent to Reset (Clear Stores). 111@ PLESSEY details of current status. The Autodialler/Terminal Identifier is an extension to the TELEVIEW system that is designed to perform the Autodialling function of a Viewdata system, to transmit the terminal identification (ID) code and to allow the remote programming of all the stored numbers. The system consists of a PIC1650-536 attached to the TELEVIEW address and data highways, an EAROM for non- volatile storage of the ID and telephone numbers and relays for controlling the telephone line. FEATURES M Non-volatile Storage of 4 Telephone Numbers of 16 Digits HM 10 IPS Loop Disconnect Dialling H@ Non-Volatile Storage of Identity Code of 16 Digits @ = Full Remote Programming Capability Mi Optional Local Programming M Easy Connection to Teleview System M@ = Spare memory locations PACKAGE PIC 1650-536 40 lead DIL ABSOLUTE MAXIMUM RATINGS See PiC1650 datasheet for details. ELECTRICAL CHARACTERISTICS See PIC1650 datasheet for details. PIC1650-536 ADVANCE INFORMATION Advance information is issued to advise Customers of new additions to the Plessey Semiconductors range which, nevertheless, still have pre-production status. Details given may, therefore, change without notice although we would expect this performance data to be representative of full production status product in most cases. Please contact your local Plessey Semiconductors Sales Office for PIC 1650-536 TELEVIEW AUTODIALLER/TERMINAL IDENTIFIER SSO STORE SELECT (NPUT/OUTPUT SSt STORE SELECT INPUT/DUTPUT SS2 STORE SELECT INPUT/OUTPUT TS1 FIMESLOT (NPUTS/OUTPUTS TS2 TIMESLOT INPUTS/OUTPUTS OATA INPUT/QUTPUT TO EAROM ca OUTPUT/CARRIER PRESENT ss (GROUND) AQ ADDRESS INPUT/OUTPUT {] Al ADDRESS INPUT/OUTPUT {] A2 ADDRESS INPUT/OUTPUT [| Vss ADDRESS INPLT/OUTPUT [] AJ ADDRESS INPUT/OUTPUT AA ADDRESS INPUT/OUTPUT A5 ADDRESS INPUT/OUTPUT AB ADDRESS INPUT/OUTPUT A7 ADDRESS INPUT/QUTPUT AB ADDRESS INPUT/GUTPUT AQ ADDRESS INPUT/OUTPUT o 8 q q q q q q q READ/WAITE INPUT [[ q q q q q q q UT TO ER1400 Vix (+9.1V NOM) 3907) Von (+5 NOM) sa - 370) RESET INPUT a6 [7] OSCILLATOR INPUT as} clock ouTeuT 34[D) 07 oaTa INpuT/oUTPUT 330} DG DATA INPUT/OUTPUT 920) DB DATA INPUT/OUTPUT 3v)_ D4 DATA INPUT/QUTPUT 30] D3 vata INPUT/OUTeUT 2997) 02 DATA INPUT/QUTPUT 2a] D1 DATA INPUT/OUTPUT PIC1650- 536 271] 06 DATA INpuT/ouTPUT 269] DIAL OUTPUT (8) 25[.] MASK OUTPUT (C) 241] LINE OUTPUT (A) 14kHz CLOCK OUTPUT 2310 TO EAROM 226) Cl OUTPUT To EAROM 21] 2 OUTPUT TO EAROM DP40 Fig.1 Pin connections - top view DIGIT 4 yo DIGIT 3 c oC B L. D >| Ie 57.2 ms 5ms minimum to 77.3 ms 800 900 ms | _ IDP je 27.2 to 41.1 ms Cc MAKE 50022 | | | | B HOLDING 3002 D BREAK 5MQ REPETITION RATE 9 11 PER SECOND Fig.2 Autodialler pulses 113PIC1650-536 PIN FUNCTIONS Pin No. Name (Symbol) Function PIC 1650-536 1 Vss Ground 2 AO 3 Al Address Input/Output - connect to TELEVIEW Address Bus 4 A2 5 Vss 6 A3 7 A4 8 AS 9 A6 Address Input/Output - connect to TELEVIEW Address Bus 10 AT 11 A8 12 AQ 13 Read/Write Input/Output Control to Page Memory - connect to TELEVIEW R/W line 14 sso 15 S$Ss1 Store Select Inputs/Outputs - connect to TELEVIEW SS lines 16 SS2 3 te { Time Siot Inputs - connect to TELEVIEW TS lines 19 Data Input/Output a a Outoat Interface to EAROM non volatile memory. 20 C1 Output Pin 20 doubles as the carrier present input. 23 14kHz Clock Output 24 Line Output (A) Output to Line Looping relay 25 Mask Output (C) Output to Mask relay 26 Dial Output (B) Output to Dialling relay 27 D0 28 D1 29 D2 30 03 31 D4 Data Input/Output - connect to TELEVIEW Data Bus 32 05 33 D6 34 07 35 Clock Output Monitor point for Clock oscillator. Set frequency to 250kHz nominal 36 Oscillator Input Connect Clock oscillator components to this point 37 Reset Input Master reset input connect to corresponding pin on TELEVIEW control PIC1650 38 - No connection 39 Vop Positive supply +5V nom. 40 Vxx Positive supply to output buffers +9.1V nom. 114OPERATION Autodialler The system responds to inputs via the TELEVIEW keyboard in order to initiate the automatic dialling of the Viewdata telephone numbers. There are 4 stored telephone numbers that may be accessed by 4 keys as described in the Prestel Terminal Specification. Each Telephone number can consist of up to 16 digits including access pauses and formatting codes. The system may be operated fully automatically or with manual dialling. 1. Automatic Dialling With the system off-line and in the Viewdata mode the initial action is to press the Square (#) key. The Tele- view system will be put in the Text mode and the currently displayed Store will be cleared. The telephone Sine will be looped and the audio should be switched to a loudspeaker. Once dialling tone is heard a digit is pressed according to the Viewdata service required. Digit 1 will give the Prestel service. (Block 2) Digit 2 will give a second number for the Prestel service. (Block 3} Digit 3 will give the third number. (Block 6) Digit 4 will give the fourth number, (Block 7) If a digit is not pressed for 30 seconds after the Square (#) key the line will be released. The digits will be put onto the screen as they are being dialled and if formatt- ing characters had been loaded in the digit store the display will be spaced accordingly. If a pause had been programmed, for access to a further dial tone for example, the system will put a * on the screen and wait for release. To release the access pause the appropriate digit is pressed again and dialling will continue. If the system does not receive a manual release it will continue after a time-out of four seconds. If at the end of dialling the call fails, pressing the Square (#) key will clear the call and then start again by re- looping the line. When the required incoming carrier tone is received the modem will return its appropriate tone to the Viewdata computer which may then send the first page of data and initiate terminal identification. \f the carrier tone is not received for any reason the line will be released after 30 seconds, Once a satisfactory connection is made to the View- data computer {i.e. carrier is detected), the keypad will revert to normal Viewdata mode and dialling will not be possible. 2. Manual Dialling If the required telephone number is not stored within the terminal the call may be made using the normal telephone. The system should start off-tine and in the Viewdata mode. The number is dialled using the tele- PIC1650-536 phone in the normal way and when dialling is complete the Square (#) Key is pressed. This will put the system into the Text mode, erase the currently displayed store and hold the line, The telephone handset is replaced and once the carrier tone is received the procedure is as before. . Connection Release {f at any time the carrier detection logic detects that the carrier is lost the connection will be immediately released, The connection will also be released when the Teleview system is switched to the Picture or Teletext modes, or if the Hold Key is pressed (if available). Alternatively the appropriate computer log off procedure may be used. In all cases the content of the Teleview Stores will remain as they were at the moment of disconnection. . Remote Programming The Teleview highways will be monitored for those special ESC sequence codes that indicate the entry into the Programme-Verify mode as described in the Prestel Terminal Specification. In the Teleview System the Data Acquistion chip receives data from the Viewdata computer and normally loads data to the display store. Any codes, particularly ESC sequences, that it does not use, it puts out onto the Teleview highway system where the remote programming device may receive them. The basic programming sequences are as described in the Prestel Specification except that the data for programm- ing the EAROM will initially be put into the display store by the DA chip. The programming device will read the digits from this store and erase them after checking that they are all valid codes. The display will be blanked during programming. . Local Programming For system security, particularly in the domestic environment, the local programming of telephone numbers and identity codes is not encouraged. However, the Teleview system has been designed such that it may talk to itself and by doing this and having some additional keys (especially ESC, ENQ, ?, : and ;) a very secure local programming mode is available. The UAR/T transmit and receive clocks are connected to a single frequency, the output joined to the input and the carrier present input is forced true. The standard programming sequences may then be input to the system to read out and/or modify the content of the digit store. . Spare Storage While only the first 7 blocks of storage are defined (as ID code plus 6 telephone numbers) a further 4 blocks are available and may be accessed by the Prog- ramme/Verify sequences if required. They could, for example, be used to store alternative identity/security codes for private Viewdata systems. 115PIC1650-536 8. Programming Routine (The following is an extract from the Preste! Terminal Specification). The programming Routine is entered by a 4 character sequence ESC1 ESC2. This puts the terminal into Programme-Verify mode (See Fig. 3). The memory is divided into seven 16 character blocks. A skip block command ESC 3 is used to skip through the blocks. Default is block 1 at entry to Programme-Verify mode, After a number (O6) of skip block commands, Verify mode may be selected by ENQ, or Programme mode may be selected by ESC 4. Entry of Verify mode shall cause the terminal to trans- mit down the telephone line the contents of the current block (excluding any space-filling characters) and 75 bit/s and then revert to normal mode. Programme data shall follow ESC 4 using the numbers 0-9 for the Identity Code and the codes given below for telephone numbers. Character 3/15 (?) will be used as a space filling character after valid data characters to make the total number of characters in a block equal to 16. 3/15 (?) may also be used between parts of the number to identify natural breaks. It may then be displayed as a space if the number is displayed for the user, @.g. 176187111122??? displayed as 01 618 1111. After recieving these 16 characters the terminal reverts to normal mode. Dialler Codes {only for blocks 27) RECEIVED IS07 CHARACTER (also used for transmission after ENO for block verification) 1 DIALLED DIGIT COAN DO BWHNH = ODI OOAW PAUSE ; RESERVED SPACE FILLER ~ A delay of at least 5s will be present between the last character to be written into the memory and the next attempt to leave Normal mode. This is to facilitate the use of slow write/erase memories. Blocks 17 are defined as follows: Block 1 identity Number Block 2 Telephone Number A Block 3 Telephone Number B Block 4 Not used Block 5 Not used Block 6 Telephone Number E Block 7 Telephone Number F 116 A and B are the Prestel Computer Centre telephone numbers. E and F are the third and fourth choices. 9. Line Interface (The following is an extract from the Prestel Terminal Specification). Physical Termination British Telecom will install a Jack 96A in customers premises to access Prestel. The customer Prestel Terminal will require a suitable compatible plug (e.g. British Telecom Plug 505). DC CONDITIONS Four sets of DC conditions are specified for the line inter- face. {a) The off-line condition (idle state} applies when the terminal is not using the telephone line. (b}) The line holding condition applies when the terminal goes on-line, is sending tones to or receiving tones from the line and during inter-digit pauses. (c) The pulsing make condition applies during the make part of a dialled digit pulse. (d) The pulsing break condition applies during the break- part of a dialled digit pulse. Plug Points Resistance Capacitance {a) Off-Line 2-3 >5Mohm* <0.01pF Idle Condition 1-5 <10 ohm (b) Line 2-3 <300 ohm+ Holding Condition 1-5 >5 Mohm {c) PulsingMake 2-3 < 50 ohm 1-5 > 5 Mohm {d} Pulsing Break 2-3 > 5 Mohm 1-5 > 5 Mohm* Ailtimes Any toearth >5Mohm* <0.01uF * Measured at 250V DC. All conditions to be independent of polarity. + Measured with line currents up to 120 mA. The max DC short circuit available from line is 120mA. AC CONDITIONS When the terminal is on-line (i.e. line holding condition) it shall present an impedance between 400 and 900 ohms at an angle not greater than 45 degrees for all frequencies between 300Hz and 3400Hz between plug points 2 and 3, AUTODIALLING tf a loop disconnect autodialler is fitted then the following requirements must be met: The digit signals shall appear as loop disconnect pulses between Plug Points 2 and 3 at a repetition rate of between 9 and 11 pulses per second. The break period shall bebetween 63% and 70% of the total pulse period (break plus make). The length of the break period condition (d) of each pulse shall be within the limits of 57.2 to 77.3 ms and the length of the make period condition (c) between any two break periods shall be within the limits 27.2 to 41.1 ms. For a period of at least 5 ms before and after pulsing condition (c) shalt apply. The digit to be dialled represents the number of break pulses to be sent except that digit O represents 10 pulses. PIC1650-536 Inter digit pauses shall be provided. The duration shall be between 800 and 900 ms. During the pause, condition (b) shall apply except during the first and last 5 ms periods when condition (c) shall apply. Fig. 2 explains this diagramatically. When the terminal is transferring to the line holding state the high impedance between Plug Points 1 and 5 must not be presented more than 20 ms before the low impedance is presented between Plug Points 2 and 3. POWER UP PARITY ERROR ANY CHARACTER NOTII SEQUENCE a NORMAL MODE I eng Esc 1 ESC 2 SEND ID PROGRAMME - NUMBER VERIFY MODE BLOCK 1 (ID) I ENQ esc 4 ESC 3 VERIFY PROGRAMME BLOCK 2 BLOCK 1 BLOCK t (A) 2 ENG ESC 4 ESC 3 2 4 5 BLOCK 3 5 (B) 7 ? 2 ENQ ESC4 ESC3 ? 1 > 2 BLOCK 4 ? (c) ? / | ESC 3 : \ BLOCK 5 (D) 7 ESC 3 \ BLOCK 6 (E) 7 | ESC 3 AN BLOCK 7 (F) TON Fig.3 Flow diagram for programming iD and telephone numbers 117PIC 1650-536 APPLICATION The Autodialler/Terminal Identifier has been designed for easy incorporation into the basic Teleview system, Special care has been taken to ensure that pin connections allow an easy and logical printed circuit layout. The circuit diagram of the main electronics is shown in Fig. 4 and that of the Line Interface in Fig. 5. The system has the following power supply requirements: +91V @ 13mA + 5V @ 140mA (Relays) + 5V @ 55mA (Logic) -26V @ 8mA It may be acceptable to eliminate RLC and substitute two silicon diodes back to back across the modem side of the isolation transformer. This will be subject to approval by the British Telecom if used in Preste! equipment. *ER 1400 OR EQUIVALENT CARRIER PRESENT FROM MODEM RB 22K c1 BREAK 10K (DIAL B MASK C H f--() LINEA 2t alll till = L l ? 28 Be lslslglalsisisls fig S9ES-0S9L Id Baoseenecaaggas Tee S TIC V ES ke RARE ec 1 <r SS r < 5 3 2 as a % [ELLE i ral UTE Sams 23 1 151818 lg 13 18 1a 18 >> 2 al 2 82 g 2 a a SBE 3 < 9 s@ q a 9 ik oO j32 & Den olz BRSBR #s BPTTHVeLesVeVsHRRRee y g 2 8 3 6 e ga Fig.4 Auto dialler add on circuit for Teleview 18PIC1650-536 LINE Oo TO MODEM TEL , N Vv a. . . a. i. R3/ 110K R5| 110K R7} | 10K LINE DIAL MASK (Ass R2 TR1 B)ss R4 TR2 (C) R6 TR3 c2 3K3 BC327 10K 2N3906 10K 2N3906 10K s s s Dit o24 D3 4 inaoo1 & RLA Iwa0014 RLB 1Na001 4 RLC F F F re 2 o 1 RLA CLARE CUP-V 10301 RLB CLARE CUP-V 10201 RLC CLARE CUP-V 10001 GD1 CERBERUS UC 900 Ri 100 ohms FS1 - 250mA quick blow, ES4265 c1 2uF Fig.5 Teleview line switching 119