Page 221
TMP89FM42
RA001
16.9 Data Sampling Method
The UART receive control circuit starts RT clock counting when it detects a falling edge of the input pulses to the
RXD0 pin. 15 to 17 RT clocks are counted per bit and each clock is expressed as RTn (n=16 to 0). In a bit that has 17
RT clocks, RT16 to RT0 are counted. In a bit that has 16 RT clocks, RT15 to RT0 are counted. In a bit that has 15 RT
clocks, RT14 to RT0 are counted (Decrement). During counting of RT8 to RT6, the UART receive control circuit
samples the input pulses to the RXD0 pin to make a majority decision. The same level detected twice or more from
among three samplings is processed as the data for the bit.
The number of RT clocks can be changed in a range of 15 to 17 by setting UART0CR2<RTSEL>. However, sam-
pling is always executed in RT8 to RT6, even if the number of RT clocks is changed (Figure 16-7).
Figure 16-7 Data Sampling in Each Case of UARTCR2<RTSEL>
RT15
14
13
12
11
10 9 8 7 6 5 4 3 2 1 0
16
15
14
13
12
11
10 9 8 7 6 5 4 3 2 1 0
15
14
Bit 0
Start Bit
Bit 0
Start Bit
(b) UARTCR2<RTSEL> is “001B”
RT clock
Internal received
data
RT15
14
13
12
11
10 9 8 7 6 5 4 3 2 1 0
15
14
13
Bit 0
Start Bit
Bit 0
Start Bit
(a) UARTCR2<RTSEL> is “000B”
RT clock
RXD0 pin
RXD0 pin
RXD0 pin
RXD0 pin
RXD0 pin
Internal received
data
RT16
15
14
13
12
11
10 9 8 7 6 5 4 3 2 1 0
16
15
14
13
12
11
10 9 8 7 6 5 4 3 2 1 0
16
Bit 0
Start Bit
Bit 0
Start Bit
(e) UARTCR2<RTSEL> is “100B”
RT clock
Internal received
data
RT14
13
12
11
10 9 8 7 6 5 4 3 2 1 0
15
14
13
12
11
10 9 8 7 6 5 4 3 2 1 0
15
14
13
12
11
10 9 8 7 6 5 4 3 2 1 0
14 13 12 11
Bit 0
Start Bit
Bit 0
Start Bit
(d) UARTCR2<RTSEL> is “011B”
RT clock
Internal received
data
RT14
13
12
11
10 9 8 7 6 5 4 3 2 1 0
14
13
12
11
10 9 8 7 6 5 4 3 2 1 0
14
13
12
11
10
Bit 0
Bit 1
Bit 1
Bit 1
Bit 1
Start Bit
Bit 0
Start Bit
(c) UARTCR2<RTSEL> is “010B”
RT clock
Internal received
data
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: ......