Can't get a 16F88 to do anything.

[Archangel]

Hi ccowley,
Welcome to The Forum, let's pretend, just for hoots, that you are a complete newbie, and we are the starving code hungry dogs,<b> I did say we are pretending didn't I ?</b> Throw us some bones of your startup code, maybe a little meat on those bones (a loop or 2 ), a little copy paste of what you have tried . . . and we'll see if you did something wrong, just so you don't have to edit the hex later

[ccowley]

Hi again,

Thanks to both of you for your input! I really appreciate the response, but things still aren't working. I did read through the entire thread that was linked to (among others) and tried everything that was suggested. The code snippit below is the from that thread and is the one I have been working with today. I have spent another 4 hours playing with this thing and it just isn't going.

I have repeated the results with two different bread boards and two different power supplys and I have rotated through 4 diffent chips and get the same results. I have checked my power and ground connection also. I can't remember ever have this kind of trouble with a microcontroller (well, okay, there were a few hairy times back in wirewrap days in college with a certain 6502 chip).

So, here is the code that I am using:

OSCCON = %01101110 'set int osc to 4mhz
'OSCON = %01100000
ANSEL = 0 'ALL DIGITAL
CMCON = 7 'COMPARATORS OFF

TRISA = %00000000 'ALL OUTPUTS
TRISB = %00000000 'ALL OUTPUTS
PORTA = 0 'PORTA LOW

@ DEVICE MCLR_OFF, INTRC_OSC, WDT_ON, LVP_OFF, BOD_OFF, PWRT_ON, PROTECT_OFF
Pause 100 'SETTLE DOWN

START:
High PORTA.6 'ON LED
High PORTA.7
Pause 1000
Low PORTA.6 'OFF LED
Low PORTA.7
Pause 1000
GoTo START 'REPEAT FOREVER

end

I have also tried it with the edited INC file and unedited INC file as mentioned in the other thread, but it doesn't change anything.

One odd note is that RB5 is always a constant 5V on every chip that I have tried so far (up to 4 now). I checked it with a scope to see if it was a clock signal or something, but it is a solid 5v.

Thanks in advance!

Carl

[mikendee]

Hi Carl,
I usually use
OSCCON = %01101000 and it seems to work. Don't forget the Define OSC for speeds other than 4MHz.
Hope this helps.
Mike

[ccowley]

Hi Mike,

Thanks for taking a look at it. I tried the OSCCON value that you suggested and it still didn't work. I am beginning to wonder if it must be a compiler error, but I'm sure I'm not the only one using these that is still on PBP 2.47. I ordered upgrade to PBP 2.50 today just in case, but I'm not conviced that's the answer.

Thanks again,

Carl

[mackrackit]

If you are using MPLAB then try this config

@__config _CONFIG1, _INTRC_IO & _WDT_ON & _LVP_OFF & _CP_OFF &_MCLR_OFF

[ccowley]

Hi Dave,

I only use MPLab for programming the chip it isn't used for anything else. The current fuses show up perfectly in MPLab when I import my code into it. If I change them, they change in MPLab with next import. I have also turned off the 'set from code' on import and set them manually, but still no luck.

I suppose I could change MicroCode Studio's setup so that it used MPLabs assembler (I have used it that way before) instead of PBP's and then I could use the fuse settings that you listed. It might be worth a shot. I will check it on Monday.

Either I am missing something really simple or this thing just isn't compiling/programming correctly as far as I can tell. My PICStartPlus programmer has the most current software upgrade too. Monday I'm going to try it all with a different computer and my other PICStartPlus programmer. I also order one of MicroEngineering Labs new programmers along with the PBP upgrade, so I'll see if that makes any difference. My current version of PBP is supposed to work with the F88 though, so I am at a loss.

My current setup is working fine with the other PIC's I am programming and using in other projects, but I need some of the extras in the F88 for another project and I am just not getting anywhere with this bad boy.

Thanks for the suggestions,

Carl

[Archangel]

try this using MPASM assembler:

OSCCON = %01101110 'set int osc to 4mhz
OSCTUNE = 0   ' SET TO CENTER FREQ

ANSEL  = 0 'ALL DIGITAL
ADCON0 = 0
ADCON1 = 0
CMCON  = 7 'COMPARATORS OFF
DEFINE OSC 4

TRISA = %00000000 'ALL OUTPUTS
TRISB = %00000000 'ALL OUTPUTS
PORTA = 0 'PORTA LOW
@ __config _CONFIG1, _INTRC_IO & _WDT_ON & _LVP_OFF & _CP_OFF &_MCLR_OFF
;@ DEVICE MCLR_OFF, INTRC_OSC, WDT_OFF, LVP_OFF, BOD_OFF, PWRT_ON, PROTECT_OFF
Pause 100 'SETTLE DOWN

START:
High PORTA.6 'ON LED
High PORTA.7
Pause 1000
Low PORTA.6 'OFF LED
Low PORTA.7
Pause 1000
GoTo START 'REPEAT FOREVER

end

or this for PM assembler

OSCCON = %01101110 'set int osc to 4mhz
OSCTUNE = 0   ' SET TO CENTER FREQ

ANSEL  = 0 'ALL DIGITAL
ADCON0 = 0
ADCON1 = 0
CMCON  = 7 'COMPARATORS OFF
DEFINE OSC 4

TRISA = %00000000 'ALL OUTPUTS
TRISB = %00000000 'ALL OUTPUTS
PORTA = 0 'PORTA LOW
;@ __config _CONFIG1, _INTRC_IO & _WDT_ON & _LVP_OFF & _CP_OFF &_MCLR_OFF
@ DEVICE MCLR_OFF, INTRC_OSC, WDT_OFF, LVP_OFF, BOD_OFF, PWRT_ON, PROTECT_OFF
Pause 100 'SETTLE DOWN

START:
High PORTA.6 'ON LED
High PORTA.7
Pause 1000
Low PORTA.6 'OFF LED
Low PORTA.7
Pause 1000
GoTo START 'REPEAT FOREVER

end

A genuine 2 bit blinky

[nomad]

i had 3 16f88's that no matter what i did, they would not run with internal osc. pop a crystal and 2 caps and not another problem since.