BasicMicro - Forums

Well it was worth the try...

If it were me, some of the things I would try include:

1) Adding extra debug code, that either printed data to S_OUT or to LEDS or... that showed if and what data was received on P12. So you can see if the data is garbled. I would also hook up my logic analyzer, but that is cheating .

2) Try different IO pins.

3) Play around with some init code. Maybe the Nano is now not properly putting P12 into an input pin. So try adding:
input p12
Just before the serin command.

4) Like 3, but maybe modify or check with some of the PIC registers associated with this IO pin. I have not done anything with PICs before so I am only guessing, but I think there are at least 3 registers (PORTA, TRISA, ANSEL) associated with this IO pin. Maybe the appropriate bit is not set in ANSEL to make it a normal IO pin...

5) Verify wiring. That is Do I have both a signal wire coming from the other board to the NANO, but do I also have a ground wire.

Good Luck
Kurt

So how are you getting it to work the first time? Right after programming the chip it works? What about after a reset(not a power down)? Also is that the whole program or is that a trimmed down version?

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Basic Micro - Robotic Technology Evolved

Yes it works after programming the chip. I power up, program the chip, unhook the serial programing cable and I can happily turn lights on from across the room sending 1's and 2's from my laptop connected to the radio. I can send the command 50 times, works fine, I can leave it sit and run for hours, works fine. I can turn off the radios, then turn them back on, it works fine. I just can't power down the chip, if I do, it hangs after the LED flashes on.

The board this is running on does not have a reset switch. RES pin is pulled high via a 10K resistor. But obviously it is resetting at power up since it always runs the first part of the program which turns on the LED. And that is the entire program, like I said it's not doing much.

Kurt, I have tried other pins, the Nano SER pin itself, different boards (of the same design), all have the same problem.

I had hoped someone would just say you forgot this, or do this you idiot, and it would be fixed. This is not something I do as a hobby, it's a means to an end. So I don't spend a lot of time working with uC's other than to do a specific job now and then. So something that may seem very basic may well be over my head. Again, thanks for the ideas.

Scott

Well I suggest you wire up that reset pin so you can reset it. Then we can see if it is purely a power on issue and you can get out of it with reset or it, it is a more general problem.

Also did you add in the timeout I suggested? Please post your updated code. The only way the program can freeze up after the led turns off is if the serin command never gets a start bit. Any change of the serin line will look like a start bit so even garbage should keep it from freezing up.

Change your program to this:



This should cause the led to toggle every 100ms if no data is received on the serial port. If data is received but it is garbage it will toggele every 500ms. If a valid command is received the delay will be 1700ms.

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Basic Micro - Robotic Technology Evolved

Nathan,

Yes, I tried using a timeout early on, no luck. I'll try adding a manual reset and the code you indicated. But I've got the project buttoned up now so I'll have to wait until the weekend after next to look at it seriously again. I'm just going to program the chip an hour or so before it'll be put to use. It's working fine that way and I've tested it numerous times without a problem.

Thanks,

Scott