Erratic behavior with a PIC16F88 and an custom LCD Board

[russman613]

Thanks for the response. Properly setting those registers did not seem to help my specific problem.

Additionally, I set the OSCCON to 0 and used HS in the HW programmer (with external 20Mhz resonator) and that did not make a difference - still seeing flakey bahaviour.

I set:

define OSC 8
OSCCON=%01110110

and it was still flakey.

I am starting to suspect that my board is just bad. I wired it on a breadboard and it was reliable without the resonator though i had to jiggle the wires around quite a bit to get it to work.

russ

[mister_e]

OK.. you're using an external OSC, BUT not the MCLR pin, so just make MCLR pin as I/O OR tie it to Vdd via 10K resistor... it should work Better.

If you're using an external OSC, the OSCCON stuff won't change anything. So i bet that..

@ DEVICE PIC16F88, HS_OSC 'HS oscillator
@ DEVICE PIC16F88, WDT_ON 'Watchdog Time
' (http://www.hobbyprojects.com/pic_tut...utorial13.html)
@ DEVICE PIC16F88, PWRT_ON '15.5 Power-Up Timer: Provides a fixed delay of
' 72 ms (nominal) on power-up only. It is designed to keep the
' part in RESET while the power supply stabilizes.
@ DEVICE PIC16F88, BOD_ON '15.7 Brown-Out Detect
@ DEVICE PIC16F88, MCLR_OFF 'Master Clear Options set to Internal. RA5 unavail
@ DEVICE PIC16F88, LVP_OFF '15.18 Low Voltage Programming via ICSP.
@ DEVICE PIC16F88, CPD_OFF '15.1 bit 8 - Data EE Memory Code Protection bit
@ DEVICE PIC16F88, WRT_OFF '15.1 bit 10-9. FLASH Program Memory Write protection off
@ DEVICE PIC16F88, DEBUG_OFF '15.1 bit 11. DEBUG: In-Circuit Debugger Mode bit
' In-Circuit Debugger disabled, RB6 and RB7 are general
' purpose I/O pins
@ DEVICE PIC16F88, CCPMX_OFF '15.1 bit 12. CCPMX: CCP1 Pin Selection bit
' 1 = CCP1 function on RB0
' 0 = CCP1 function on RB3
@ DEVICE PIC16F88, PROTECT_OFF 'Code protection off

could help

[russman613]

Whose the stud?? Steve aka mister_e, that's who!

Thx much for noticing my problem with the MCLR fuse setting.

I changed it to the correct value (MCLR_OFF since i don't have reset wired in my schematic) and voila - flowers and discount surplus parts rained from the sky to bring happiness to the masses - even though they were sober and balding ...

Very much appreciate the attention to detail. Thanks again for your assistance.

Russ

[Archangel]

CONGRATULATIONS russman613 and
<font color=red><h1> Hurray for mister_e !</h1></font color> the devil is always in the details! Nice catch Steve!

[mister_e]