6 C51 6.1 6.2 51 6.3 C51 6.3 6.5

51UART481011351

51515151

6.1 6.1.1 6.1.2 6.1.3 PC

6.1.1 6.1

1. (Asynchronous Communication)

(Character Frame)46.21)

2) (Baud Rate)b/s/ 509600b/s

2. (Synchronous Communication)6.3SYNCRC3

56000b/s6.4

6.1.2 (Simplex)(Half Duplex)(Full Duplex)36.5

6.1.3 UART/USRTUSART CPUCPUCPU

RS-232CRS-449RS-422RS-423RS-48520mARS-232RS-232C

RS-232C(DCE)(DTE) RS-232C020000b/s(15m) RS-232C

1. RS-232C RS-232C2125 RS-232CDDB-256.6DB-25DB-15DB-9

6.6 DB-25

2. RS-232C TTLRS-232CTTLTTL(MC1488MC1489MAX232) RS-232CTTLTTLRS-232CRS-232C315V0315V133V

6.2 516.2.1 6.2.2 6.2.3 51UART4810113

6.2.1 6.7SBUFSBUFPCONSCONTIRI

1. () SBUFTI(T1T2)TXD(P3.1)SBUFTI =1CPUTISBUF

2. () REN(/)RI()(SBUF)RIRXD(P3.0)SBUFRI=1RI

6.2.2 51SFRSCONPCON

1. SCON SCON98H06.8

2. PCON PCONCHMOS87HHMOSPCON6.9

6.2.3 SCONSM1SM040I/O123 40213T1

1. 0 08fosc /12RXD(P3.0)TXD(P3.1)

1) SBUF8fosc /12RXD()TI1TI02) REN=1RI=0RXDfosc/12()8RI1RI0

0I/O(74LS164CD4094)(74165CD4014) SCONTB8RB808TIRI1CPUTIRI00SM20

3) 0fosc1/126.1 874LS1646.108D1D8 74LS1646-2

6-2 74LS164

6.2 874LS1656.1170K11K22K770 74LS1656-3

6-3 74LS165

2. 1 110UARTRXDTXD10108116.12

1) TXDSBUFTI12) REN1RXD100RI=01SM2=0RB8RI1RISM2

k0k=131k=1623k=8T126-43) 1T1PCONSMOD

6-4 T1

6.3 12MHz1/121200b/s26

3. 2 211UARTSMOD111(0)81()1(1)6.14

1) TB8SBUFSBUF8SBUFTB89 TI1TI

2) REN=1RXD11RXD9RI=0SM2=0918SBUF9RB8RI=1

3) SMODPCON76.4 12MHz2909AFASCII 2

4. 3 311UART216.5 316RecData[16]fosc =11.0592MHz2400b/sPSW.5(F0)10

6.3 C51 6.3.1 6.3.2 TIRITIRITI=1RI=1TIRI1

6.3.1 6.166.176.6 6.18U1U2U2P1.0P1.1P1.2U2U10x01U2U10x02U2U10x03

6.3.2 6.196.206.7 6.21U1U2P1.0P1.1P1.2U1U20x010x010x020x020x030x03

6.20

6.4 2. 1. PC 3. 3

4. UART/USART 5. 51UART4810113

6. 51SCONPCON 7. TIRI1

6.5 6.22U1U2U1P13K1K2K3U2P13D1()D2()D3() K1D1K2D2K3D3K1D1K2D2K3D3K1K2K3D1D2D3

6.22

12T1234D1D2D3K1K2K3 (1) D1D2D3 (2) K1D1K1D1K1D2D3 (3) K2D2K2D2K2D1D3 (4) K3D3K3D3K3D1D2

6