Hello. I'm reading MODBUS holding registers. On register 0 the value is -35 (signed). If I show this value in gage the value is 65501 (unsigned). How can I show SIGNED INTEGER? Thanks. BR.

What do you get coming out of whatever node you are using for modbus? Feed it directly into a debug node and screenshot please.

is that directly from the MODBUS node? Some of the modbus nodes output a buffer object. And if it is a buffer then its pretty simple : in a function node (untested)... let buf = msg.payload; msg.converted = []; msg.converted[0] = buf.readInt16BE(); msg.converted[1] = buf.readInt16BE(); msg.conver…

[image] Colin: msg.payload[i] = (msg.payload[i] << 16) >> 16 Collin you are the best. Simple and effective sollution. BR.

Collin. Off topic question. Do you have similar (simple) idea of how to show BCD formated numbers? I have posted: OMRON BCD format Thanks. BR.

Ask for further help on that thread. One poster described how to do it, if that is not in sufficient detail then ask for further clarification.

MODBUS 16bit SIGNED INTEGER

General

Colin 23 April 2020 14:38 6

To use the data as in the debug then you can do, for each item in the array
msg.payload[i] = (msg.payload[i] << 16) >> 16

How to decode 16 bit unsigned integer

Can anyone explain to me why this works...? (Signed integer data)

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MODBUS 16bit SIGNED INTEGER

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