PIC18F258 Datasheet, PDF (180/384 Pages) Microchip Technology – High Performance, 28/40-Pin Enhanced FLASH Microcontrollers with CAN

PIC18FXX8
FIGURE 17-27:
BUS COLLISION DURING START CONDITION (SCL = 0)
SDA = 0, SCL = 1
SDA
TBRG
TBRG
SCL
Set SEN, enable START
sequence if SDA = 1, SCL = 1
SEN
BCLIF
SCL = 0 before BRG time-out,
bus collision occurs. Set BCLIF.
S
’0’
SSPIF ^{’0’}
SCL = 0 before SDA = 0,
bus collision occurs. Set BCLIF.
Interrupt cleared
in software
’0’
’0’
FIGURE 17-28: BRG RESET DUE TO SDA ARBITRATION DURING START CONDITION
SDA
SDA = 0, SCL = 1
Set S
Less than TBRG
TBRG
SDA pulled low by other master.
Reset BRG and assert SDA.
Set SSPIF
SCL
SEN
BCLIF
S
SCL pulled low after BRG
Time-out
Set SEN, enable START
sequence if SDA = 1, SCL = 1
’0’
S
SSPIF
SDA = 0, SCL = 1
Set SSPIF
Interrupts cleared
in software
DS41159B-page 178
Preliminary
 2002 Microchip Technology Inc.