Hello, here are a few things I need to know :

1. I want to use bits 3 and 4 of PORTC for SCL and SDA when working with
    the I2C bus. I'm single master of this bus. My question is how to
initialise
    this I2C-bus ?? I wrote some code. Does this code make any sense and
   didn't I forget something ?

    The declaration of the variables looks like this :

#DEFINE SCL             PORTC,3         ;SCL PIN
#DEFINE SDA             PORTC,4         ;SDA PIN

INIT_I2C

      BCF           STATUS , RP0
      CLRF         PORTC
      BSF           STATUS , RP0
      MOVLW    B'11100111'
      MOVWF   TRISC

      RELEASEBUS                         ; Don't know what this is and what
it does ?
                                                          ; Think it's a
macro. Think it makes SDA and
                                                          ; SCL high.
      CLRF        BUS_STATUS       ; Signalisation FLAG !!
      RETURN

Is it so that you have to make SDA and SCL high to release the bus ??

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2. The following code that I found is a delay for 4.7 us :

Delay47uSec
       movlw ((_47uS_Delay-8)/3 + 1)
DlyK
        movwf DelayCount
        decfsz DelayCount
        goto $-1
        return

How does it work ?
What is _47uS_Delay ? It's probably defined somewhere else !!

goto $-1 --> a loop ??

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3. Slaves are allowed : Clock stretching ??

But when you have fast slaves, you don't have to implement this
in your software. How do I know I have to implement it or not ?
The I2C bus I'm working with is one inside a SONY TV. They
told me that the I2C it uses, is not the fast on (400k ??)

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4. I have a program where each operand is preceded by  an underscore _
    Why's that ?


So that will do it for now !!

All comments or advice are very welcome !!

Greetings,

Glenn Goovaerts