I am attempting to add an Ultimate GPS to my Ice Tube Clock to improve it's accuracy. I have updated the firmware in my clock and wired the GPS as described in the mods page for the clock. The clock does not receive the GPS data as it flashes "no gps" even though the GPS has a lock on satellite signals (I ran it over night).
I've read posts where people have asked if the Ultimate GPS is compatible with the Ice Tube Clock and the answers were affirmative. However, in reading the description page of the GPS, I note that the GPS module sends NEMA data at 9600 baud. The notes on the Ice Tube Clock mods page say it receives data at 4800 baud. At the moment I believe this is the source of at least one problem, and one reason the two won't play together.
I've searched and seen no references on this specific issue in the forums. If you find something, please point me there.
So my tentative plan is (was?) to wire-up the Ultimate board to my serial port, run the Mini GPS Tool (per the tutorial page) and adjust the NEMA string baud rate to 4800 from 9600.
But I am facing two issues:
First, the tutorial does not show how to wire directly to the serial port (in my case via an USB-to-Serial adapter), rather it shows how to wire the GPS to an Arduino. I don't have an Arduino. I can probably figure this one out on my own; I'll research the pin-outs on serial ports and solder-up something and see what I can accomplish.
EDIT: Okay, after researching and thinking about it I see that I'll need a RS-232-to-TTL converter; I've ordered one (FTDI Friend + extras).
The second issue is that upon researching this on the forums, I see that some people have apparently bricked their Ultimate GPS units when attempting to use the GPS Software Tool to configure them (for logging, baud rates, etc.). See post: http://forums.adafruit.com/viewtopic.php?f=19&t=28940&hilit=gps
While the support team says not to change the baud rates of the GPS, I interpret this as, "Don't INCREASE the baud rates of the GPS beyond 9600". I need to DROP the baud rate to 4800 so the clock can read it. Is that okay? Also, I am not interested in fast update rates (e.g. 1 Hz, 5 Hz, 10 Hz, etc), I could live with updates every few minutes since all I am doing is updating the clock's time setting. Therefore I don't need a higher baud rate anyway - all I need to do is get the two on the same rate so they can play nice.
Do I run the risk of bricking the GPS? The thread referenced above has no conclusion so I am spooked on the idea of attempting to change anything. Any suggestions? Has anyone else done this? Has anyone else updated their Ultimate board without bricking the unit?
Thanks in advance for any assistance.