DIYDrones,
I'm wondering if anyone can answer a simple question related to the MAVLink messages sent from the APM. I am running a program that uses a XBEE via USB to monitor the messages sent from the APM. When I run this program, using an APM1, I see over 10 different messages sent from the APM. These messages are sent from pwr on, until the APM is powered down. Moreover, only heartbeat messages are sent until the APM is initialized. But, once initialized, the APM sends many different messages.
The problem comes about when I try to do the same using the APM2 hardware. The APM2 will only send out heartbeat messages (id#0) and an occasional STATUSTEXT message (id#253). Why doesn't the APM2 send just as many messages as the APM1?? Is the APM2 waiting for a response before it starts sending all of the messages that the APM1 will send? I'm deadlocked at this point in my program, and need to be able to use the APM2 hardware while monitoring the mavlink messages. Does anyone know why the APM2 is not sending these messages?
Replies
David,
Michael O and Tridge probably know better than me but I think that the APM2 does wait for a request message from the GS saying which messages it wants...but i'm not sure. I'm surprised there's a difference between APM1 and APM2.
Hello David,
You need to have the data stream rates configured correctly. To do so, connect to Mission Planner. Go to configuration. Locate EEPROM parameters and verify that you have the following parameters configured as here:
SR0_EXT_STAT,2
SR0_EXTRA1,15
SR0_EXTRA2,10
SR0_EXTRA3,3
SR0_PARAMS,50
SR0_POSITION,3
SR0_RAW_CTRL,0
SR0_RAW_SENS,25
SR0_RC_CHAN,3
SR3_EXT_STAT,2
SR3_EXTRA1,15
SR3_EXTRA2,5
SR3_EXTRA3,3
SR3_POSITION,0
SR3_RAW_CTRL,0
SR3_RAW_SENS,25
SR3_RC_CHAN,0
Change accordingly and save the parameters to APM. The numbers refer to the telemetry data rate for the specific message group. The data rates in the list above are just suggestion. Hope this can help you.
Pedro