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TMP89FM42
RA001
18.5.4 Stop condition generation
When SBI0CR2<BB> is "1", a sequence of generating a stop condition is started by setting "1" to
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.
When a SCL line on a bus is pulled down by other devices, a serial bus interface circuit generates a stop con-
dition after a SCL line is released.
The time from the releasing SCL line until the generating the STOP condition takes t
HIGH
.
Figure 18-21 Stop Condition Generation
18.5.5 Restart
Restart is used to change the direction of data transfer between a master device and a slave device during
transferring data. The following explains how to restart the serial bus interface circuit.
Clear SBI0CR2<MST>, SBI0CR2<TRX> and SBI0CR2<BB> to "0" and set SBI0CR2 <PIN> to "1". The
SDA0 pin retains the high level and the SCL0 pin is released.
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
released.
Example :Generate the stop condition
LD
(SBI0CR2), 0xD8
; Sets SBI0CR2<MST>, <TRX> and <PIN> to "1" and SBI0CR2<BB> to
"0"
CHK_BB:
TEST
(SBI0SR2).BB
;Waits until the bus is set free
JR
T, CHK_BB
Stop condition
If the SCL of the bus is pulled
down by other devices, the stop
condition is generated after it is
released
SDA0 pin
SCL0 pin
SCL (Bus)
SBI0CR2<PIN>
SBI0SR2<BB>
SBI0CR2<MST>="1"
SBI0CR2<TRX>="1"
SBI0CR2<BB>="0"
SBI0CR2<PIN>="1"
Summary of Contents for TLCS-870/C1 Series
Page 1: ...8 Bit Microcontroller TLCS 870 C1 Series TMP89FM42 查询TMP89FM42供应商 捷多邦 专业PCB打样工厂 24小时加急出货 ...
Page 3: ...Revision History Date Revision 2007 10 25 1 First Release 2007 11 3 2 Contents Revised ...
Page 4: ......
Page 14: ......
Page 18: ...1 3 Block Diagram TMP89FM42 1 3 Block Diagram Figure 1 2 Block Diagram ...
Page 22: ...1 4 Pin Names and Functions TMP89FM42 ...
Page 60: ...2 CPU Core 2 5 Revision History TMP89FM42 ...
Page 76: ...3 Interrupt Control Circuit 3 8 Revision History TMP89FM42 ...
Page 86: ...4 External Interrupt control circuit 4 3 Function TMP89FM42 ...
Page 102: ...7 Voltage Detection Circuit 7 5 Revision History TMP89FM42 ...
Page 126: ...8 I O Ports 8 3 I O Port Registers TMP89FM42 Note 2 i 0 to 1 ...
Page 136: ...8 I O Ports 8 5 Revision History TMP89FM42 ...
Page 142: ...9 Special Function Registers 9 3 SFR3 0x0E40 to 0x0EFF TMP89FM42 ...
Page 146: ...10 Low Power Consumption Function for Peripherals TMP89FM42 ...
Page 149: ...TMP89FM42 11 3 Revision History Rev Description RA001 Deleted SLEEP2 description ...
Page 150: ...11 Divider Output DVO 11 3 Revision History TMP89FM42 ...
Page 220: ...15 Real Time Clock RTC 15 4 Real Time Clock Operation TMP89FM42 ...
Page 250: ...16 Asynchronous Serial Interface UART 16 15 Revision History TMP89FM42 ...
Page 302: ...18 Serial Bus Interface SBI 18 7 Revision History TMP89FM42 ...
Page 338: ...21 Flash Memory 21 4 Toggle Bit D6 TMP89FM42 ...
Page 384: ...22 Serial PROM Mode 22 15 Revision History TMP89FM42 ...
Page 388: ...24 Input Output Circuit 24 1 Control Pins TMP89FM42 ...
Page 404: ...25 Electrical Characteristics 25 11 Revision History TMP89FM42 ...
Page 406: ...26 Package Dimensions TMP89FM42 ...
Page 408: ......