tmp89fm42 TOSHIBA Semiconductor CORPORATION, tmp89fm42 Datasheet - Page 297

• Manufacturer Part Number: tmp89fm42
• Description: 8 Bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

RA001
Example :Generate the stop condition
18.5.4 Stop condition generation
18.5.5 Restart
SBI0CR2<MST>, SBI0CR2<TRX> and SBI0CR2<PIN> and clearing SBI0CR2<BB> to "0". Do not modify
the contents of SBI0CR2<MST>, SBI0CR2<TRX>, SBI0CR2<BB> and SBI0CR2<PIN> until a stop condi-
tion is generated on a bus.
dition after a SCL line is released.
transferring data. The following explains how to restart the serial bus interface circuit.
SDA0 pin retains the high level and the SCL0 pin is released.
released.
When SBI0CR2<BB> is "1", a sequence of generating a stop condition is started by setting "1" to
When a SCL line on a bus is pulled down by other devices, a serial bus interface circuit generates a stop con-
The time from the releasing SCL line until the generating the STOP condition takes t
Restart is used to change the direction of data transfer between a master device and a slave device during
Clear SBI0CR2<MST>, SBI0CR2<TRX> and SBI0CR2<BB> to "0" and set SBI0CR2 <PIN> to "1". The
Since this is not a stop condition, the bus is assumed to be in a busy state from other devices.
Check SBI0SR2<BB> until it becomes "0" to check that the SCL0 pin of the serial bus interface circuit is
CHK_BB:
SCL (Bus)
SBI0CR2<PIN>
SCL0 pin
SDA0 pin
SBI0SR2<BB>
SBI0CR2<MST>="1"
SBI0CR2<TRX>="1"
SBI0CR2<BB>="0"
SBI0CR2<PIN>="1"
LD
TEST
JR
Figure 18-21 Stop Condition Generation
(SBI0CR2), 0xD8
(SBI0SR2).BB
T, CHK_BB
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;Waits until the bus is set free
; Sets SBI0CR2<MST>, <TRX> and <PIN> to "1" and SBI0CR2<BB> to
"0"
If the SCL of the bus is pulled
down by other devices, the stop
condition is generated after it is
released
Stop condition
HIGH
.
TMP89FM42