Specifications Archive Appendix KOEM4 Family Installation and Operation User Manual Rev 12 193INPUT/OUTPUT DATA INTERFACECOM1, COM2 AND COM3Electrical format RS232 (Can be factory configured for LVTTL or RS422 operation)Bit ratea 300, 1200, 4800, 9600 (default), 19200, 57600, 115200, 230400 bpsLead input CTS (and DCD on COM2)Lead output RTS (and DTR on COM2)Signals supported TX, RX, RTS, CTS, DTR, DCD (DTR and DCD are on COM2 only)a. Baud rates higher than 115,200 bps are not supported by standard PC hardware. Special PC hard-ware is required for higher rates, including 230,400 bps.INPUT/OUTPUT STROBESMSR (Measure Output) Normally high, active low where the pulse width is 1 ms. The falling edge is thereceiver measurement strobe.Event1 (Mark1 Input) An input mark (negative pulse > 55 ns), time tags output log data to the time ofthe falling edge of the mark input pulse.PV (Position Valid) Output indicates a ëgood solutioní or a valid GPS solution when high.ERROR Output that Indicates fatal error warning when high.STATUS_RED Status output which is high or pulses to indicate that the OEM4 card is notworking properly.STATUS_GREEN Status output which pulses to indicate that the OEM4 card is working properly.PPS (One Pulse PerSecond)Normally high, active low pulse is 1 ms wide @ 1 Hz. Falling edge is used asthe reference.VARF (VariableFrequency)A programmable variable frequency output ranging from 0 - 20 MHz (refer to theFREQUENCYOUT command in Volume 2 of this manual). This is a normallyhigh, active low pulse.RESETOUT Reset TTL signal output to external system; active high.RESETIN Reset TTL signal input from external system; active low, > 1 μs duration.STROBE ELECTRICAL SPECIFICATIONSOutput Voltage: LVTTL levelsLow:High:minimum 0 VDC and maximum 0.55 VDC @ 24 mAminimum 2.4 VDC and maximum 3.6 VDC @ 8 mAInput Voltage: LVTTL levelsLow:High:minimum 0 VDC and maximum 0.8 VDCminimum 2.0 VDC and maximum 5.5 VDC
