Communications Card Description ZB4-601-IF1, ZB4-609-IF1 4-37
Moeller 07/01 AWB-C2700-1347GB
SPECIAL NOTE
Data is normally transferred in word or double word format, e. g.:
1R0141 HI-BYTE LO-BYTE
1R0142 HI-BYTE LO-BYTE
1R0143 HI-BYTE LO-BYTE
1R0144 HI-BYTE LO-BYTE
All values in the PASE, however, are “24-Bit” (3 BYTE) in length.
In the range 1R and 3R the ZB4-601/609-IF1 sends a 00 for the most significant 8 bits:
This has the disadvantage that only bytes (range 0...255) and words (range 0...65535) can be sent, whilst
ShortIntegers (range –128...+127) and Integers (range –32768...+32767) cannot.
If the most significant bit (in this case bit 7) of a ShortInteger is set the value is negative:
ShortInteger : –1 = FF
h
; –2 = FE
h
; –128 = 80
h
; 127 = 7F
h
...
The value –5, for example, is represented in the PASE accordingly as 251 (0000FB
h
) instead of FFFFFB
h
and must be converted inside the PLC:
The same applies to the Integers (2 bytes).
The ranges 2R and 4R are reserved exclusively for LONG values since they are also transferred in a special
way by the DRIVER.
BSP 2R0241 HI-BYTE LO-BYTE
2R0242 HI-BYTE LO-BYTE
2R0243 HI-BYTE LO-BYTE
2R0244 HI-BYTE LO-BYTE
transferred 2R0241 MED-BYTE LO-BYTE
2R0241 UNUSED HI-BYTE
2R0243 MED-BYTE LO-BYTE
2R0243 UNUSED LO-BYTE
The two registers 242 and 244 are therefore not written and can be used as required in the PLC program.
Long values are normally in the range of +/–2,147 billion (32-bits). The min MIN/MAX for the PASE must not,
however, exceed +/–8,388 million (24-bit).
Higher values are shortened by the DRIVER to 24-bit and are therefore transferred incorrectly.
ShortIntegers and Integers are also not permissible in these ranges!
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