ABB 266 MODBUS User Manual page 20

2 System description
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MODBUS communication can be configured to emulate three different transmitter register maps:
— ABB transmitter 267/269 (Default)
— Rosemount 3095FB
— Invensys IMV25
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Go to Appendix C, MODBUS register lists for detailed MODBUS register tables.
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Mapping tables assign 16 bit system objects to 32 bit register addresses. This allows the MODBUS Master to select and use a
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single addressing mode. The MODBUS processor zero-fills any undefined 16 bit objects. The defined bits occupy the LSB
(least significant (lower) bits) and the zeroed bits are the MSB (most significant (higher) bits). A 32 bit register address is
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mapped the same way as a single 16 bit register address. MODBUS communication prevents a protected register object from
being overwritten.
12 | 266 MODBUS® multivariable transmitter User manual 2105216 Rev. AB