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Tips and questions relating to the GPS modules from SFE
By Sparks333
I picked up the OEM version of the Lassen iQ for a UAV board I'm working on. It's small and light, so it looks friendly enough, but when trying to interface with it over a USART in a PIC, it violates the TSIP protocol rather flagrantly - I transmit the data streams 0x10 0x21 0x10 0x03 (a time check in accordance with the TSIP packet protocol), and it sends back 0x40 0x74 0x40 0x07, which not only violates protocol, but is entirely unusable. Furthermore, upon further experimentation, it sends that string no matter what I do. I'm on a bit of a deadline here, and really like this GPS, but it's beginning to bother me. Am I doing something wrong here? Is it just a bad chip?

Thanks in advance!

By Sparks333
Well, this is disheartening.

In any case, I found an underlying issue - the baud rate was a touch off, not enough to preclude all communication, but enough to screw everything up. There is still an issue, however. When I send a command packet with the right syntax, it replies with the correct ID, but not any data packets or stop or start bytes. Very disturbing.