
A-90188E-01 SETTING 1.MODBUS/TCP SERVER FUNCTION
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Concurrency of word data (2-byte data)
To ensure data concurrency, the following two conditions must be
observed:
(1) In the ladder program, the following instructions must be used in
units of two bytes:
DECB, CODEB, DCNVB, COMPB, DSCHB, XMOVB, ADDB,
SUBB, MULB, NUMEB, MOVN, EOR, AND, OR, and NOT
instructions
(2) When AREA1-3 is assigned to PMC %M, %ME or %R
addresses, %M, %ME or %R addresses must be on 2-byte
boundaries.
The 2-byte boundaries mean that a PMC address number satisfies
the following condition.
- For PMC %M, %ME addresses:
(8×n)+1 [The even of n = 0 - 7999]
Example) %M1, %M17, %ME1, %ME17
- For PMC %R addresses:
n/2+1 [The even of 4 of n = 0 - 9999]
Example) %R1, %R2