ET2020/EFA Elapsed Time Indicator ET2020/EFA Features * EEPROM non-volatile memory. * 10 years data retention. * Low power, 10 mW typical. * Serial and parallel outputs. * Microprocessor compatible. * Non-volatile text storage and recall. * Military specifications. Note: The Test pin is provided for factory purposes For ordering information see page 22. only and should be left unconnected. Construction The 18 pin ceramic dual-in-line package is assembled using thick film chip hybrid technology, ensuring suitability for military, avionic, and industrial applications where severe environmental conditions maybe encountered. VAUX Output Select Request Time Count Tx Rx Data Valid Test VSS 1 2 3 4 5 6 7 8 9 18 17 16 15 14 13 12 11 10 VCC D7 D6 D5 D4 D3 D2 D1 D0 16.2 mm (0.638") max 15.24 mm (0.600") CRS Pin 18 0.25 mm (0.010") nom 0.56 mm (0.022") max www.oxleygroup.com/eti ODCSM40539/2/2005 5 mm (0.197") nom 30.4 mm (1.197") nom 5 mm (0.197") nom 3 mm (0.600") nom Pin 1 Pitch 2.54 mm (0.100") Oxley Group Australia Pty Ltd Email: sales@oxleygroup.com Tel +61 (0) 2 9967 9488 Oxley Inc. Email: sales@oxleyinc.com Tel: +1 (203) 488 1033 Oxley Developments Company Ltd Email: sales@oxley.co.uk Tel: +44 (0)1229 483226 15 ET2020/EFA Application Circuit Diagrams Typical application ODCSM40539/2/2005circuit diagrams are shown below for serial and parallel interrogation modes. The internal timer is activated whenever the 5 V power supply is applied. No additional timing control circuitry is required. The total elapsed time is accumulated in the internal non-volatile memory for interrogation through either the serial or parallel interfaces. Serial Mode 5 Volt Equipment Supply ET2020/EFA VAUX TX RX RS 232 Level Shifter VCC Output Select D7 Request Time D6 Count Tx D5 D4 Rx Data Valid D3 D2 Test VSS D1 D0 0 Volts Parallel Mode 5 Volt Equipment Supply Data Valid ET2020/EFA VAUX Request Time VCC Output Select Request Time D7 D6 Count Tx D5 D4 Rx Data Valid D3 D2 Test VSS D1 D0 External Control Circuitry 8 bit - Tristate Data Bus 0 Volts 16 Oxley Developments Company Ltd Email: sales@oxley.co.uk Tel: +44 (0)1229 483226 Oxley Inc. Email: sales@oxleyinc.com Tel: +1 (203) 488 1033 Oxley Group Australia Pty Ltd Email: sales@oxleygroup.com Tel +61 (0) 2 9967 9488 www.oxleygroup.com/eti ODCSM40539/2/2005 ET2020/EFA Power Supply A single 5 Volt power supply, Vcc is required for operation. A separate power supply input Vaux is also provided for energisation from a second power source. A blocking diode is internally connected to prevent current from Vaux powering parent equipment connected to Vcc. This provides cold read facilities during failure of parent equipment or when it is powered down. Interrogation The ETI can be interrogated in either serial or parallel format. The OUTPUT SELECT (OS) input is used for selection of interrogation mode. Serial Data (Output Select = 0) Serial data transfer uses two pins, Rx (receive data), and Tx (transmit data). Together with a signal common, these lines constitute a 3 wire serial communication interface utilising a standard non-return to zero (NRZ), data format. Direct interface can be made with integrated circuit UART devices. The signals can also be level shifted to conform to RS232 requirements. The Rx and Tx signals must meet the following requirements:1 A High level indicates logic 1 (5 V) and a low level indicates logic 0 (0 V). 2 The Rx input must be in a high state prior to reception of data. 3 A start bit, (logic 0), is transmitted/received indicating the start of a message. 4 Bytes of data are transmitted/received least significant bit first. 5 A stop bit, (logic 1), in the 10th bit position indicates transmission/reception of a byte is complete. 6 Baud rate: Data bits: Start bits: Stop bits: Parity: 9600 b/s 8 1 1 None To initiate transmission of serial elapsed time/pulse count data a unique two character ASCII command "ET" must be received at the Rx input. Following reception of a valid "ET" command the ETI will output the elapsed time message on the Tx output. If an invalid command is received an ASCII carriage return character, (0D hex), is transmitted. www.oxleygroup.com/eti ODCSM40539/2/2005 Oxley Group Australia Pty Ltd Email: sales@oxleygroup.com Tel +61 (0) 2 9967 9488 Oxley Inc. Email: sales@oxleyinc.com Tel: +1 (203) 488 1033 Oxley Developments Company Ltd Email: sales@oxley.co.uk Tel: +44 (0)1229 483226 17 ET2020/EFA Serial Elapsed Time Interrogation VCC "E" "T" Rx "CR" Tx "H" "CR" Byte Byte Byte Byte Byte Byte 6 1 2 3 4 5 900 ms min Byte Byte Byte 10 11 12 6 ms max 1 ms min Bytes 1 and 12 are ASCII carriage return characters. Bytes 2 to 9 represent the elapsed time reading and are ASCII characters. Byte 2 is the most significant digit. Byte 7 is always "." and byte 11 "H" denoting units of hours. Elapsed time measurement is suspended for typically 300 ms during serial data output. BYTE 1 2 3 4 5 6 7 8 9 CHARACTER cr 0 0 0 0 0 . 0 0 HEX 0D 30 30 30 30 30 2E 30 30 10 20 11 12 H cr 48 0D Parallel Data (Output Select = 1) Parallel elapsed time/pulse count interrogation is initiated by holding the REQUEST TIME input at logic 0 for time tRT or until the positive edge of DV(1). The elapsed time/pulse count time information then appears sequentially in 3 bytes on outputs D0-D7. Data is synchronised with pulses which appear on the DATA VALID (DV) output. Each byte represents a 2 digit BCD number. Outputs D7-D4 represent the most significant digit, outputs D3-D0 represent the least significant digit. D0-D7 are tri state outputs suitable for direct connection onto a high impedance data bus. Parallel Text Interrogation Parallel text interrogation is initiated by holding the REQUEST TIME input at logic 0 for the time tRTT or until the positive edge of DV(4). Following the 3 bytes of elapsed time/pulse count information, the ASCII text appears on outputs D0-D7 synchronised with DATA VALID pulses DV(4) to DV(53). To request elapsed time information only, the REQUEST TIME pulse width should not exceed tRT max. Elapsed time measurement is suspended for typically 300 ms during parallel data output. 18 Oxley Developments Company Ltd Email: sales@oxley.co.uk Tel: +44 (0)1229 483226 Oxley Inc. Email: sales@oxleyinc.com Tel: +1 (203) 488 1033 Oxley Group Australia Pty Ltd Email: sales@oxleygroup.com Tel +61 (0) 2 9967 9488 www.oxleygroup.com/eti ODCSM40539/2/2005 ET2020/EFA BCD Parallel Output t t t t ZDV t t Vcc t RT DS t I t RTP OT OET RTT RT t SDV DV t DV DV(1) PDV HIGH IMPEDANCE DV(2) DV(3) DV(4) DV(5) DV(6) DV(7) DV(53) D0 HIGH IMPEDANCE HIGH IMPEDANCE D1 HIGH IMPEDANCE HIGH IMPEDANCE D2 HIGH IMPEDANCE HIGH IMPEDANCE D3 HIGH IMPEDANCE HIGH IMPEDANCE D4 HIGH IMPEDANCE HIGH IMPEDANCE D5 HIGH IMPEDANCE HIGH IMPEDANCE D6 HIGH IMPEDANCE HIGH IMPEDANCE D7 HIGH IMPEDANCE HIGH IMPEDANCE READING = 1234.56 "T" "E" "X" "T" "$" During DV(1) the digits represent HOURS x 103 and HOURS x 102. During DV(2) the digits represent HOURS x 101 and HOURS x 100. During DV(3) the digits represent HOURS x 10-1 and HOURS x 10-2. Parameter tI Description Initialisation time Min Max 900 tRT Request time pulse width for time information only 6 tRTT Request time pulse width for time & text information 16 tSDV Time to set up 1st data valid tDV Data valid pulse width tPDV Period of data valid tOT Units ms 12 ms ms 6 ms 90 110 s 4.99 5.01 ms Total bus active time 264 ms tOET Total bus active time, elapsed time only output 15 ms tZDV Time from end of Z state to 1st DV 175 typical s tDS Data set up time 90 typical s tRTP Request time repetition period 300 ms www.oxleygroup.com/eti ODCSM40539/2/2005 Oxley Group Australia Pty Ltd Email: sales@oxleygroup.com Tel +61 (0) 2 9967 9488 Oxley Inc. Email: sales@oxleyinc.com Tel: +1 (203) 488 1033 Oxley Developments Company Ltd Email: sales@oxley.co.uk Tel: +44 (0)1229 483226 19 ET2020/EFA User Programmable Text 50 bytes of EEPROM are provided for user entry and storage of 50 characters of text information. The text may record, for example, maintenance and warranty status of parent equipment. Text may be rewritten as often as required and can be read by both serial and parallel outputs. Text can only be entered serially. Text Entry Text entry can only be made whilst in serial mode and is initiated by detection of the ASCII "IX": command at the Rx input. Up to 50 ASCII text characters should then be input, terminated either by a carriage return or by entry of the 50th character. Text entered will overwrite previously stored text. Serial Text Input VCC "I" Text 1 "X" Text 2 Text 3 Text 50 Rx "CR" Tx 900 ms min 5 ms min 1 ms min 0.2 ms typical 0.1 ms min Serial Text Interrogation Serial text interrogation is achieved by using the ASCII "OX" command.Serial Text Output VCC "O" "X" Rx "CR" Text 1 Text 2 Text 50 "CR" Tx 900 ms min 6 ms max 1 ms min 20 Oxley Developments Company Ltd Email: sales@oxley.co.uk Tel: +44 (0)1229 483226 0.1 ms typical Oxley Inc. Email: sales@oxleyinc.com Tel: +1 (203) 488 1033 Oxley Group Australia Pty Ltd Email: sales@oxleygroup.com Tel +61 (0) 2 9967 9488 www.oxleygroup.com/eti ODCSM40539/2/2005 ET2020/EFA Typical Drive Current Graph 7.0 6.0 ID (mA) 5.0 4.0 3.0 2.0 1.0 0.5 1.0 1.5 VCC - VOH (volts) www.oxleygroup.com/eti ODCSM40539/2/2005 Oxley Group Australia Pty Ltd Email: sales@oxleygroup.com Tel +61 (0) 2 9967 9488 2.0 Oxley Inc. Email: sales@oxleyinc.com Tel: +1 (203) 488 1033 Oxley Developments Company Ltd Email: sales@oxley.co.uk Tel: +44 (0)1229 483226 21 ET2020/EFA Characteristics Operating temperature range -55C to 125C Storage temperature range -55C to 125C Supply voltage, VCC 4.5 to 5.5 V d.c. Supply voltage, VAUX 4.0 to 5.5 V d.c. Supply current 2 mA typical, 4 mA max. Timing resolution 0.01 hours Timing accuracy 0.1% Capacity (PARALLEL MODE) 104 hours /106 pulses Capacity (SERIAL MODE) 105 hours /107 pulses VOH, Output logic 1 VCC-1 to VCC Iload <1ma VOL, Output logic 0 VSS to 0.4V VIH, Input logic 1 0.8 x VCC to VCC VIL, Input logic 0 VSS to 0.2 x VCC IZ, High Z leakage current 10 A Ordering Information Elapsed Time Indicator Order Code ET2020/EFA When ordering please state Type No. and quantity required. 22 Oxley Developments Company Ltd Email: sales@oxley.co.uk Tel: +44 (0)1229 483226 Oxley Inc. Email: sales@oxleyinc.com Tel: +1 (203) 488 1033 Oxley Group Australia Pty Ltd Email: sales@oxleygroup.com Tel +61 (0) 2 9967 9488 www.oxleygroup.com/eti ODCSM40539/2/2005