Propeller resetting - I think?

Mike G

I believe I’m having a problem with the Propeller resetting.

My project is to control a ½ duplex 1Mpbs bus with a STAMP using the Propeller as middleware. The Propeller receives commands from a STAMP and forwards the data to the AX-12 Dynamixel network (1Mbps). I have 1k resistors between the STAMP pins and the Propeller pins.

I have the STAMP setup to ping the bus forever. I get the Prop application loaded then reset the STAMP. The very first ping might not receive a response but all successive pings do. I would guesstimate that 75% of the time the first ping is not successful.

I think that resetting the STAMP is causing the problem but I’m not sure. Any ideas?

Mike Green

1) What parts of your demo are already known to work?

2) How are you powering things? Most problems with unexpected resets are due to either marginal power or software errors.
The kinds of software errors are usually RETURN without GOSUB on the Stamp and too small a stack for secondary cogs and
errant programs using out-of-range pointers that overwrite other parts of the program or stack area.

3) To catch Stamp resets, use a short DEBUG statement at the beginning of your program. If the Stamp resets, the DEBUG
statement will execute and you'll see repeated DEBUG output on your connected PC.

4) To catch Propeller resets, you can use an extra pin with an LED on it (and series resistor) and just flash the LED for 1/2 second
at the beginning of your main program before you initialize the various serial routines.

Mike G

Thanks Mike

Sorry, my original post was not detailed enough. The whole enchilada works. The only time I have an issue is when I press the STAMP’s reset button. The STAMP is not resetting by itself.

For power I’m using a variable power supply and Parallax issued wall transformers.

Since my last post I did a few things like sending the Propeller output to a terminal app and scoping the Tx/Rx lines. It appears that the prop is sending a signal back every time. So I might be having a timing issue with the STAMP.

I’ll check out the LED test. That’s a great idea. Wish I would have thought of that.

Mike G

I executed the simple but effective LED reset test. The prop is not resetting! Now I can X that off the list of things to check.