Hi everyone,

It's 2 years now that i'am read the list and now i'am trying my first "real"
project.
It's based on 16f876:
The working part:
                Seriale interface 232 using interrupts
                Modubus protocol func. 1 to 6 using interrupts
                Magnetic Card Reader using interrupts
                I2C routine for RTC and ext EEprom using polling

My perplesity is that a polling routine can get stuck in the middle
and never return to the main cycle. I tried doing I2C with interrupts
on PIR1, SSPIF but it seems to me that I never can clear it. I tryed
a couple of weeks and then gave up.
The real question is does peolple ("programmers") use polling or interrupts
for I2C. Any help ?


; ***** Routine x pulire SSPIF
**********************************************
clear_sspif
   bcf      PIR1, Bit3              ; SSPIF
   btfsc    PIR1, Bit3              ; SSPIF
   goto     clear_sspif
   return

; ***** Routine x cercare SSPIF alto
****************************************
poll_sspif
   btfss    PIR1, Bit3
   goto     poll_sspif
   return

; ***** Start routine per iniziare TX o RX del I2C
start_i2c
   bsf      PORTC, Bit3
   bsf      PORTC, Bit4
   go_bank1
   bsf      SSPCON2, SEN
   go_bank0
   return

stop_i2c
   go_bank1
   bsf      SSPCON2, PEN
   go_bank0
   return

recieve_i2c
   go_bank1
   bsf      SSPCON2, RCEN
   go_bank0
   return

master_ACK
   go_bank1
   bcf      SSPCON2, ACKDT
   bsf      SSPCON2, ACKEN
   go_bank0
   return

master_NOT_ACK
   go_bank1
   bsf      SSPCON2, ACKDT
   bsf      SSPCON2, ACKEN
   go_bank0
   return

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