PIC18F25J11-I/PT MICROCHIP [Microchip Technology], PIC18F25J11-I/PT Datasheet - Page 318

• Manufacturer Part Number: PIC18F25J11-I/PT
• Description: 28/44-Pin, Low-Power, High-Performance Microcontrollers with nanoWatt XLP Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F46J11 FAMILY
18.5.17.3
Bus collision occurs during a Stop condition if:
a)
b)
FIGURE 18-33:
FIGURE 18-34:
DS39932C-page 318
After the SDAx pin has been deasserted and
allowed to float high, SDAx is sampled low after
the BRG has timed out.
After the SCLx pin is deasserted, SCLx is
sampled low before SDAx goes high.
SDAx
SCLx
PEN
BCLxIF
P
SSPxIF
SDAx
SCLx
PEN
BCLxIF
P
SSPxIF
Bus Collision During a Stop
Condition
BUS COLLISION DURING A STOP CONDITION (CASE 1)
BUS COLLISION DURING A STOP CONDITION (CASE 2)
SDAx asserted low
Assert SDAx
T
BRG
T
BRG
T
BRG
T
BRG
The Stop condition begins with SDAx asserted low.
When SDAx is sampled low, the SCLx pin is allowed to
float. When the pin is sampled high (clock arbitration),
the BRG is loaded with SSPxADD<6:0> and counts
down to 0. After the BRG times out, SDAx is sampled. If
SDAx is sampled low, a bus collision has occurred. This
is due to another master attempting to drive a data ‘0’
(Figure 18-33). If the SCLx pin is sampled low before
SDAx is allowed to float high, a bus collision occurs. This
is another case of another master attempting to drive a
data ‘0’ (Figure 18-34).
SCLx goes low before SDAx goes high,
set BCLxIF
T
BRG
T
BRG
© 2009 Microchip Technology Inc.
SDAx sampled
low after T
set BCLxIF
‘0’
‘0’
‘0’
‘0’
BRG
,