PIC16F87XA
FIGURE 9-27:
BUS COLLISION DURING START CONDITION (SCL = 0)
SDA = 0, SCL = 1
TBRG
TBRG
SDA
Set SEN, enable START
sequence if SDA = 1, SCL = 1
SCL
SEN
SCL = 0 before SDA = 0,
bus collision occurs. Set BCLIF.
SCL = 0 before BRG time-out,
bus collision occurs. Set BCLIF.
BCLIF
Interrupt cleared
in software.
S
’0’
’0’
’0’
’0’
SSPIF
FIGURE 9-28:
BRG RESET DUE TO SDA ARBITRATION DURING START CONDITION
SDA = 0, SCL = 1
Set S
Set SSPIF
Less than TBRG
TBRG
SDA pulled low by other master.
Reset BRG and assert SDA.
SDA
SCL
S
SCL pulled low after BRG
time-out
SEN
Set SEN, enable START
sequence if SDA = 1, SCL = 1
BCLIF
’0’
S
SSPIF
Interrupts cleared
in software.
SDA = 0, SCL = 1
Set SSPIF
2001 Microchip Technology Inc.
Advance Information
DS39582A-page 105
MICROCHIP [ MICROCHIP ]
