Hi All,
I have managed to get my APM up and running using two XBee 2.4Ghz modules without any problems, however if I swap these modules over and replace them with the XBee Pro 900Mhz modules I get no data coming over the link. I have set my baud rate to 9600 on both ends and in the APM just to be safe, since that appears to be the maximum RF baud rate supported.
What I have noticed is that if I use the test -> xbee mode of the ArduPilot I get "00" bytes coming through to my serial terminal on the PC. About one a second.
Has anyone else encountered similar problems, did I miss something somewhere in the documentation regarding the way the Pro 900 chips work vs the 2.4Ghz ones?
Thanks
Shaw
Replies
Hi Shaw,
I've been having a simliar problem when using XBeePro XSCs with an Arduino Mega. I'm receiving zeros at the serial port.
One problem could be that I'm using Xbee explorers from Sparkfun which may have a current limit problem on transmit (i.e. the regulator is only 150mA, but the XSC needs 265mA). Another problem could be the VIO levels (Xbee 3.3V) to ArudinoMega 5V - I think usign the Adafruit adapter would rule this out, but I don't have one.
Have you had any success?
Duncan.
You have the wrong Xbee modules.
The Xbee 900 Pro XSC has a maximum data rate of 9.6 kbps
The Xbee 900 Pro has a maximum data rate of 156 kbps
Thomas - I don't have one in fornt of me just now - but I'm willing to bet that's the default, and therefore exactly what I've done wrong.
I'll let you know how I get on when I try it later..
Hi Chris,
I did notice that - I changed a few of the defaults:
#define GCS_PROTOCOL GCS_PROTOCOL_LEGACY
#define GCS_PORT 3
#define SERIAL3_BAUD 9600
It works fine if I use the 2.4Ghz modules, but not with the 900Mhz ones...
I'm powering the APM off the USB port and I wonder if there isn't enough current to drive the 900Mhz module vs the 2.4Ghz one? Is this likely?
All telemetry is sent at 57k unless you've changed it in the config file.
It's all spelled out in the manual. Is something there unclear?