| IWR-PORT SERIES
UTILITY OPERATING MANUAL
C
opyright © 2021 Sensata Technologies, Inc.
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16-bit output link values if they are unlocked (see below)
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16-bit burnout level values if they are unlocked (see below)
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16-bit burnout timeout values if they are unlocked (see below)
Multiple writes are also possible, using function code 0x10. A maximum of 8 registers can
be written in one command string.
Writing to register 48000 to unlock scaling and link table registers
Write 0x0000 to register 48000 to gain write access to the span and zero scaling values,
link table. Write 0x0001 to lock them again, as they are at power-up.
Writing 16-bit Data Values:
To calculate the 16-bit unsigned integer register offset please refer to the IWR-Port
Modbus register table (128 channel, 8 parameters).
The IWR-Port output and Isoslice units that have outputs can have values written to them
via Modbus, provided they have been set up to allow this (see section 6.5).
An isoslice unit with a digital output can have a digital value written to it.
A digital output value is 0x0000 = off, 0x0001 = on.
For analog outputs, 16-bit data values are written as unsigned integers representing a
number between –6.7% and 106.7%. 100% and 0% correspond to the output span and
zero points learned at calibration.
Output value = (%Value x 577.81) + 3869
e.g. 0%
3869d
0x0F1D
100%
61650d
0xF0D2
50%
32759d
0x7FF7
Writing 16-bit Span Point Scaling Values:
To calculate the 16-bit span point register offset please refer to the IWR-Port Modbus
register table (128 channel, 8 parameters).
Scaling values are written as unsigned integers.
They will only be changed by the IWR-Port if the Scaling values are
unlocked, by first writing 0x0000 to register 48000
The scaling value must fall in the range of –999 to 9999
For positive numbers convert to hexadecimal
e.g. 1000 converts to 0x03E8
