S3B, SM=1, PC=0. Occasionally booting into command mode.

Question

I have some XSC radios that appear to be booting into command mode instead of idle mode.

I am using pin sleep so...
SM = 1;

But PC is 0 so it should boot into idle mode.
PC = 0;

So I don't think that the PC command is the issue. But when I power them up from a cold boot I have to wait 20 seconds for command mode to timeout, before my data transmission starts.

Answer 1

Hello Aaron,

You may be pulling the Config pin (pin 6) low during boot. If this is done, the module will go into Command Mode.

This is something that was carried over from the older XStream radio.

If you are using a 3rd party interface board, this may be happening. I have seen this on boards from Parallax and a few others.

Have a great day!

Comments

Pin 6 is floating on my design.
Thanks for the response!

Answer 2

Well, I got the strange behavior to stop by adding a 100ms delay on power up before sending UART data. It now boots into idle mode like it should.

The only pins I have hooked up on my design are 1,2,3,9 and 10.