Hello Everyone,

EXPERIMENT 1

I have a 16F676 @ 4MHz communicating with 24LC256 using RC1 (SDA, with
1K pull up) and RC2 (SCL).

I am using bit bang technique.

As observed on an oscilloscope, the SDA and SCL lines raise to 5V and
fall to 1V but not to 0V.

I removed the 24LC256 thinking it could be pulling the line high.

Again, as observed on an oscilloscope, the SDA and SCL lines raise to 5V
and fall to 1V (above TTL level) but not to 0V.

I started single stepping the code. Now the SDA and SCL both raise to 5V
and fall to 0V.

I inserted some 10 uS delay between SDA and SCL lines changing the
state. Still no success.

EXPERIMENT 2

Removed the 24LC256.

Ran the below code.

	bsf portc,scl
	bsf portc,sda
	goto $+1
	bcf portc,scl
	bcf portc,sda
	goto $-5

Same results.

If I run this with 5 mS delay then the I/O lines reach 0v.

I am unable to understand this behavior.

Has anyone come across this type of behavior?

Cheers

Ravi
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