GPS related subpage of GenBoard/UnderDevelopment/FirmWare
GPS logging is implemented with PDA and PC, see PdaCockpit
It could make sense to capture the GPS when logging to SD card. Logging to SD card will be supported (blockwrite works, reading and output formatting must be added), but SD+GPS likely not in near future. The recommended method is to connect GPS to PC or PDA (not to the controller).
- connect a GPS module to the second serial port (either 0/3V FBUS or -/+8V RS232 voltage level)
- and just report some data on the LCD
- log (later, when MMC is ready)
Mattias small development project
Questions
- Is the bytestuffed format solid enough with todays firmware? (1.2.26+)
- Is bytestuffed format required for GPS + normal ECU logging parameters?
Use cases
- It would be useful to be able to have the option of using either the 1st or 2nd serial port for NMEA communication.
- NMEA GPS module connected to 1st port, datalogging to MMC
- Laptop, Android or AIM display connected to 1st port, NMEA GPS module to 2nd, datalogging through 1st
- Using 1st port for NMEA requires communication to be robust enough.
- AIM, Trigger frame format and NMEA on the same port.
Hardware
- A couple of these has been ordered : GlobalSat BR355-S4 SiRF Star iV GPS module
- http://www.usglobalsat.com/p-689-br-355-s4.aspx
- PS/2 connector for GND, VCC+, RX, TX
- Weatherproof
Hardware
There are several modules out there, some popular ones:
- GARMIN http://www.garmin.com (prolly exists for cheaper)
- GPS18 very common come in usb and rs232 about $70
- GPS35 just over $100
- GA 27C - GPS  $70 i think it is everything
- GPS-JP10 Falcom GPS SiRF-3 15 300 Ft
- GPS-JP7-T Falcom GPS SiRF-2 9 990 Ft
- GPS-JP7-TX Falcom GPS SiRF-2 XTrack2 12 980 Ft
- GPS-TIM-LC TIM GPS no Flash 11 430 Ft
- GPS-TIMB TIM GPS receiver mchip 13 380 Ft
- TIM GPS demo vevőmodul TIM + táp + RS-232 + SMB 21 000 Ft
- Emil found "NMEA GPS Modules" on ebay for as low as $80/5 ! Sounds like a good buy (hopefully not too risky).
Above prices are wholesale purchase prices (1 Ft = 0.005 USD), without antenna, VAT, shipping, and support.
I propose Jason buys appr. 10..20 NMEA modules from ebay for WebShop (developers and finally anyone).
This module requires some simple glue circuitry like supply, voltage level conversion (max232) and initialization commands.
The NMEA device will output standard NMEA messages. They are meant for integration into a system, so setting them up to get the messages and the baud rates you desire may require some special code. There is no simple user's manual, the manuals are more like system spec. documents.
The NMEA message would look like:\nÿ1ÿ
An earlier format Marcell has seen and used is somewhat more dense:\nÿ2ÿ
but any format should do.
David Helland already has PCB and PCB design for the Falcom and uBlox receivers
- PCB board is 31mm x 66mm
- the schematic (Orcad), layout (PADS), gerbers and parts lists
- 6 PCB boards left over from a proto run
- PCB mounts the module with glue logic and connectors
- supplies clean 3.3V
- interfaces with the module's 3.3V IO
-  A daughter board with conditioned (vehicle spike protection) power supply and RS-232 drive chips (max232) would be required.
Either David could easily revise to design to include this. Or we can design a new PCB (especially if it's for the NMEA), the circuitry sounds relatively simple.
David suggests: by the time you put all this together, you will be close to the price of off-the-shelf handheld GPS receivers (about $100 USD).
Marcell thinks this can be solved cheaper with our manufacturing capabilities if Q>40 (which it will be).
Antenna
Remember that microwave antenna and cabling is always a pain.
Although it is possible to place the unit in GenBoard/VerThree Alubos case with an endplate-mounted connector, it's more efficient (and general! think: many customers for usage without v3.x) to get an appropriate box and use cable for serial conn + power rather than microwave.
- antenna at ebay (from $15) with SMA ? connector
- ... ?
Box
Small offtheshelf box: suction type would be nice for mounting
- ... ?