p16f877 Microchip Technology Inc., p16f877 Datasheet - Page 93

• Manufacturer Part Number: p16f877
• Description: 28/40-pin 8-bit Cmos Flash Microcontrollers
• Manufacturer: Microchip Technology Inc.

FIGURE 9-21:
FIGURE 9-22:
2001 Microchip Technology Inc.
SDA
SCL
SEN
BCLIF
S
SSPIF
BCLIF
S
SSPIF
SDA
SCL
SEN
BUS COLLISION DURING START CONDITION (SCL = 0)
BRG RESET DUE TO SDA COLLISION DURING START CONDITION
SDA pulled low by other master.
Reset BRG and assert SDA.
’0’
’0’
SCL = 0 before BRG time-out,
Bus collision occurs, Set BCLIF
’0’
Set SEN, enable START
sequence if SDA = 1, SCL = 1
Less than T
BRG
SDA = 0, SCL = 1
SDA = 0, SCL = 1
T
BRG
SDA = 0, SCL = 1
Set SSPIF
Set SEN, enable START
sequence if SDA = 1, SCL = 1
s
Set S
T
T
BRG
BRG
Set SSPIF
SCL = 0 before SDA = 0,
Bus collision occurs, Set BCLIF
SCL pulled low after BRG
Time-out
Interrupts cleared
in software
’0’
’0’
Interrupts cleared
in software
PIC16F87X
DS30292C-page 91