[time-nuts] Re: Both TruePosition boards does not work

[Ben Hall]

On 11/18/2024 9:58 AM, Alexandre Souza via time-nuts wrote:
> Danke, herr Ziggy...but unfortunately this is already done, and even before
> the $proceed the trueposition boards shows some gps messages. But there is
> just no activity whatsoever. Serial is correct at 9600 n 8 1, power supply
> is correct, antenna is working and with good view of sky, jumoer on pins 4
> and 5 of the 6 pin connector, but no activity on rs232 AND ttl serial port.

Greetings Alexandre and all!

So...I'm looking thru my Arduino TruePosition interface code.  Seems that before I do *anything* with the unit, I send it the $PROCEED command.  In fact, I do it twice, just to be sure:

delay(5000);
Serial.println("$PROCEED");
delay(5000);
Serial.println("$PROCEED");

It has been a long time since I've looked at the TruePosition serial output, but I'm 99.9% sure it won't send anything out the serial port until it's been issued the $PROCEED command.  No GPS messages, no nothing.  In fact, the TruePosition units don't send any sort of normal NMEA or other known GPS messages - it has it's own format...

Looking thru my old notes, I see I wrote down that before "$PROCEED" is issued, the board is in bootloader mode.  I also see some notes where I wrote that sending any characters to the board before PROCEED is issued may cause issues to the bootloader.  That's why I wait 5 seconds, send it, wait 5 seconds, and send it again.  Don't ask me where / why I wrote this down, it's been too long and my memory is too poor to remember.

thanks much and 73,
ben