Is there a such thing as a VEX compatible GPS? If so, what is it?
Garmin GPS 36 would do. In fact this GPS has TTL serial communication, meaning that you would not even have to use the Vex Programming “dongal” to get it to communicate.
Also there is the Parallax GPS receiver This uses an on board SX microprocessor so it current time, date, latitude, longitude, altitude, speed and travel direction/heading.
It is a single-wire 4800 bps TTL Serial interface that needs a +5VDC supply @ 115 mA power supply. It also can be switched between raw (NMEA0183 strings) and simple mode. I haven’t used this product but am pretty certain that this will work quite well.
This would work, it is $89.00 (USD). You would still have to read the data from it and do some translation.
Do you know if there are any cheaper GPS devices for sale that can be programmed more easily?
No I don’t… The Garmin 36 supports the “NMEA 0183” and binary formats too, meaning the same Complexity to Program for.
The Garmin 36 was $225.00 (IIRC) when it was originally sold, $60.00 to $70.00 now, the Parallax GPS is much less cost new, and a lot less baggage to deal with as far as the physical package is concerned.