103696

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103696 - Serial GPS Adapter Board with Synchro Input

Description

103696 is an adapter board used with the 10369 interface board to connect NMEA 0183 serial GPS devices to the Elphel Model 353 camera.

Adapter provides 3.3V/5.0V (jumper selectable) power to the GPS device, communicates with it over RS-232 (+/-5V) TxD/RxD lines and uses optional synchronization pulse (usually 1pps) from the device. It includes USB-to-Seraial converter chip that allows full communication with the GPS device using the camera software, additionally the RxD signal is fed to the camera FPGA, decoded and logged in the camera sytem memory buffer - together with the optional IMU data, each message with the microsecond resolution timestamp. The source of the timestamp even is selectable among synchronization pulse from the GPS (either polarity), the start bit of the first NMEA sentence afther the pause or the start of each individual NMEA sentence. Current FPGA code allows programming of up to 4 different NMEA sentences that are recognized, decoded and logged.

Connectors

The board uses two alternative connectors to the GPS device:

  • standard (with extra connections for GPS power and synchro pulse) for RS-232 9-pin DSUB (male) or
  • 8-pin low profile Hirose connector

First option is used when the board is mounted on the camera body and the connector extends outside for the external GPS, the second - when the GPS is mounted inside the camera body. In that case the DSUB mounting holes are used to mount the 103696 adapter board.


J1 - to the 10369 board

connector to the 10369 board
Pin Signal Notes
1 VP33IN +3.3V power input
2 IPULSE1SEC GPS synchro pulse to FPGA, output
3 IRXD GPS data line converted to TTL levels for FPGA, output
4 SDA i2c SDA
5 SCL i2c SCL
6 GND ground
7 VP5IN USB +5V power
8 DM USB data -
9 DP USB data +
10 GND ground

J2 - DSUB-9 (male) for external GPS connection

connector to the external GPS device
Pin Signal Notes
1 PULSE1SEC GPS synchro pulse (non-standard for RS-232), input
2 RXD Serial data signal from the GPS, input
3 TXD Serial data signal to the GPS, output
4 GPSPWR GPS 3.3V power (non-standard for RS-232), output (may be changed to 5.0V on the 103696 board)
5 GND ground
6 DSR unused, connected to wirepad W1
7 RTS RS-232 RTS signal, output
8 CTS RS-232 CTS signal, input
9 RI unused, connected to wirepad W2

J3 - Internal connector for the GPS

connector to the internal GPS device
Pin Signal Notes
1 PULSE1SEC GPS synchro pulse (non-standard for RS-232), input
2 RXD Serial data signal from the GPS, input
3 TXD Serial data signal to the GPS, output
4 GPSPWR GPS 3.3V power (non-standard for RS-232), output (may be changed to 5.0V on the PCB)
5 GND ground
6 GP1 unused, connected to wirepad W3
7 RTS RS-232 RTS signal, output
8 CTS RS-232 CTS signal, input

J4 - Auxiliary GPS Power

Auxiliary power input
Pin Signal Notes
1 GPSPWR optional external power for the GPS device
2 GND ground


Set 3.3V or 5V power to the GPS receiver

The power voltage level is set with JP4 and JP5 jumpers.

JP4 & JP5 jumpers
Power JP4 JP5
3.3V disconnected connected
5V connected disconnected

Garmin GPS 18x LVC & GPS 18x-5Hz wiring

Garmin gps18x wiring.jpeg