PIC18F2221_1 Datasheet, PDF (207/402 Pages) Microchip Technology – Enhanced Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology

PIC18F2221/2321/4221/4321 FAMILY
FIGURE 18-29:
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 18-30: 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
© 2009 Microchip Technology Inc.
DS39689F-page 207