I2C and Serout problems with 18F4525

[Yuantu Huang]

Dear Steve,

I made it working as your suggestion although sometimes it doesn't go (seems no clock, it may be the circuit board problem). The following is the change of the code and cofiguration:

code:
========================
DEFINE OSC 8
OSCCON = %01110111
=======================

cofiguration:
==============================================
__CONFIG _CONFIG1H,_OSC_INTIO67_1H
__CONFIG _CONFIG2H, _WDT_ON_2H & _WDTPS_128_2H
__CONFIG _CONFIG3H, _MCLRE_ON_3H & _PBADEN_OFF_3H
__CONFIG _CONFIG4L, _LVP_OFF_4L & _ENHCPU_OFF_4L
==============================================

Once again thank you very much.

[mister_e]

Great. Try reprogram your PIC with the lowest Brown-Out-voltage treshold too. Power-Up timer have to bet set too.

Of course noisy supply line and 'weird contact' on a board can do bad results. PIC18F series are really noise sensitive... use of external pull-ups instead of the internal seems to solve some problems. After some tests, Pull-ups lower than 4.7k give better result. i use 1K in all my apps. For sure sink a bit more current but... it works.