NAiS FP Series, Руководство пользователя

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FP
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9.4 Data Transmitted and Received with the FP
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9 - 29
9.4 Data Transmitted and Received with the FP
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The following four points should be kept in mind when accessing data in the FP
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transmission and received buffers.
- Data in the transmission and received buffers, that is being sent and received, is in ASCII code.
- If the transmission format settings indicate that a start code will be used, the code STX (H02)
will automatically be added at the beginning of the data being sent.
- An end code is automatically added to the end of the data being sent.
- There is no end code on the data stored in the received buffer.
When sending data:
Data written to the transmission buffer will be sent just as it is.
Example: When the data “12345” is transmitted as an ASCII code to a
device with RS232C port.
Data sent using the F95 (ASC) instruction should be converted
to ASCII code data.
Conversion of ASCII code
“ 1 2 3 4 5 ” (Data to be transmitted)
Conversion of ASCII code
(1) (2) (3) (4) (5)
H 31 32 33 34 35 (Coded data)
Figure 193: FP
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Conversion of ASCII code
If DT100 is being used as the transmission buffer, data will be
stored in sequential order in the data registers starting from
the next register (DT101), in two-byte units consisting of the
upper byte and lower byte.
DT103 DT102 DT101
Upper byte
H35 H34 H33 H32 H31
(5) (4) (3) (2) (1)
Lower byte Upper byte Lower byte Upper byte Lower byte
Figure 194: FP
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Example (transmission buffer)