???%20?Borland%20C %20Builder??%20???????I/O????

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??? ????
Serial-Data Transmission
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????

• RS232??
• RS232????
• PC?PC?RS232????
• RS232????????

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????(??????)

• RS232??
• RS232????
• PC?PC?RS232????
• RS232????????

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RS232??

• ??(Baud Rate) ???????? ?
• 1 Baud Rate1BPS(bit per second) ?
• RS232???????

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RS232??(?)

• RS232????? RS232???????25pin D?
• ???9
  pin D????

PGD ??????????????? GND??????????
TXD ?????? RXD????? ?
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RS232??(?)

• RS232????
• 1. ????(Simplex)
• ???????????????????????,?AM?FM????
• 2. ?????(Half Duplex)
• ????????????,???????????????
• ???????
• 3.?????(Full Duplex)
• ????????????,????..?

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????(??????)

• RS232??
• RS232????
• PC?PC?RS232????
• RS232????????

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RS232????

• RS232????????(Package)??? ?
• ????????(Frame)??? ?
• ???(Frame)???????
• ???9-12?????? ?

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RS232????(?)
????1?bit ????7?8?bit
????1?bit???? ????????
Mark(???1)?None ????1?2?bit
RS232?????byte?data???17019 bits,??? 1
81212 bits ?
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????(??????)

• RS232??
• RS232????
• PC?PC?RS232????
• RS232????????

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PC?PC?RS232????

• ??????RS232???????,?????9 pin D??? (??????) ?????
• PC?PC?RS232??????????????????

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????(??????)

• RS232??
• RS232????
• PC?PC?RS232????
• RS232????????

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RS232????????

• ????RS232?????????,???????????????(Protocal) ?
• ????????,?????---???????????? ?
• ??1?????????-???????????DO
• ???

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RS232????????(?)

• ?????????????? ?
• ?????????????? ?
• ????????????,??????01
• ???????2???(00-FF)???DO????????
• ?????????data??????XOR????ASCII
• code(2byte)

??01 0F 4E ??????4E(0x34,0x45) ??01 0F 4E
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RS232????????(?)
???? 1. ??????8-3??????????????? 2.
???????,?????????????? 3. ????????8-3???