TMP91C824
91C824-167
(4)
Stop condition generation
When SBI0SR<BB> = 1, the sequence for generating a stop condition can be initiated by writing
“1” to SBI0CR2<MST,TRX,PIN> and “0” to SBI0CR2<BB>. Do not modify the contents of
SBI0CR2<MST,TRX,PIN,BB> until a stop condition has been generated on the bus. When the
bus’s SCL line has been pulled Low by another device, the TMP91CW12 generates a stop condition
when the other device has released the SCL line.
When SBI0CR2<MST,TRX,PIN> are written “1” and <BB> is written “0”, <BB> changes
to “0” by internal SCL changes to “1”, without waiting stop condition.
To check whether SCL and SDA-pin are “1” by sensing their ports is needed to detect
bus free condition.
Internal SCL
SDA pin
<PIN>
<BB> (read)
Stop condition
“1”
→
<MST>
“1”
→
<TRX>
“0”
→
<BB>
“1”
→
<PIN>
SCL pin
Figure 3.10.17
Stop condition generation ( Single-master)
Internal SCL
SDA pin
<PIN>
<BB> (read)
Stop condition
“1”
→
<MST>
“1”
→
<TRX>
“0”
→
<BB>
“1”
→
<PIN>
SCL pin
The case of pulled low
by another device
Figure 3.10.18 condition generation ( Multi-master)