PIC analogue to serial interface

[Jules_Theone]

I have started looking at PIC programming again, tried to write the firmware I had written before for the 16F688, but there were compile errors. I appear to have sorted the compiling issues and able to program the device but it doesn't seem to work as I had it before. I am using a newer version of both MPLAB and Hi-Tech compiler. I can't see where the problem is. I tried stripping the firmware down to just flash an LED (so I can build it up from there again) but I can't seem to do that right. Any help would be appriciated.

MPLAB IDE 8.83
Hi-Tech Universal Toolsuite 9.83

Thanks,

Jules.

 

[Ian Rogers]

The only thing that sticks out.... ADC_CH0 doesn't start at 0.. also when you assigned channel[k] k never increases ... It's always 0.

I'm going to run it through ISIS.... I'll get back to you.... Are you still using the pic16f688?

 

[Ian Rogers]

~ FOSC_INTOSCIO .... turns OFF the internal clock so OSC1 and OSC2 are inputs

 

[Jules_Theone]

I've double checked things with the PICKIT1 and 16F688 datasheets and it seems ok, besides I don't understand why I had it working a year ago (and still have a programmed 16F688 that works). Is there a way to get the program back from the PIC? Or can you check what I want it to do is what the code actually says.

To Ian Rogers:

The trimmer is connected to AN0/RA0 pin so I want the code to read from that input, is that what my code is doing or did you mean I'm reading from the wrong place?

I thought "k++;" on line 94 increments k. Correct me if I'm wrong.

I have several 16F688s as that seems to be the only one that has a hardware USART and can be programmed with a PICKIT1.

I have checked the pic16f688.h file (attached) for the __CONFIG and I believe FOSC_INTOSCIO means to use the internal oscillator, which i want to do.


Another idea I had was that the (pro trial) Hi-Tech compiler is optimising the code without me knowing it. Is there a better way to make it read AN0 and output it on the serial (RS232) once a second?

Thanks,

Jules.

 

[be80be]

He needs to get rid of ~ in front FOSC

 

[Ian Rogers]

Yes Burt... I should have explained that... Thanks

I thought "k++;" on line 94 increments k. Correct me if I'm wrong.

Yes but you immediately turn it back to 0.

   k++;
   if (k == 1) k = 0;
   break;

I have tried this in ISIS and it works very well.

 

[Jules_Theone]

Yes that solved it, I didn't see the added ~ in the __CONFIG line.

Thanks everyone.