GeoChron Issues

I have just purchased a GeoChron Blue for use on a consulting project and although I like the product, I am constantly butting heads with what appears to be bugs and strange features.

The most important bug for me relates to MODE 2. In this mode, you can get the logger to record things when power is applied. I am intending on logging street sweepers, logging only when the broom is down. If I set MODE 2 with 00:00:01 delay and a hold off of 5, the position reports are about 11 seconds apart, and are really choppy. This is because the GPS is being turned off after each report and being turned back on.

If I set the delay at 00:00:00, things are more bizzare. I get a delay between logged points of 5 seconds. This translates to the Hold Off time of 5 seconds. I think this comes from a bug in mode_1(void) of main.c where in the case of a zero delay, the GPS is still constantly being turned on and off.

This might also explain why the LED is green with the occasional flash when I use MODE 2.

Unfortunately I need MODE 2 to work logging each second without turning the GPS off all the time else the product will be useless to me. As the source code is all a year old, I am guessing I will need to search for another product as I do not have the skills to fix this.

Other issues…

The GPS reports as having 12 channels whilst the SFE website reports this GPS as being 20 channels. Not sure what is going on here. Also, the GPS reports ‘$PSRFTXT,WAAS Enable’. If this is just saying that it can support WAAS, then fine. If it is saying WAAS is enabled then there is an issue, since the code only enables WAAS, and restarts the GPS to disable it.

When starting up for the first time, turning the Power to 1 and Standby to 0 is required. What is not explained well in the manual is that once Standby is 1, a power cycle is needed to stop the red LED flashing. I wasted too much time on that.

The PIN for Bluetooth is 1234, and this is not in the manual at all. The Bluetooth is not as useful as it would appear as it is firstly rather hard to connect to Bluetooth, particularly in MODE 2 (Actually, I have NEVER connected in MODE 2). And if you connect, I have yet to find a way to use the Bluetooth for anything other than Config. You see, a menu item is needed to see GPS data, and mobile phone satnav software does not tend to like this.

Darryl

There is also a bug where if you attempt to use the Bluetooth serial interface to view a file on SD Card, and the file does not exist, the user will be immediately placed into the settings menu.