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Noisy Boysie avatar image
Noisy Boysie asked

Modbus TCP register 820 returning 64k not minus numbers Cerbo GX

Hi


im seeing the data returned from my

Product Cerbo GX

Firmware version v2.73

when using Modbus register 820 +64k when it should be showing minus numbers, so when the register should be showing exporting numbers eg minus im getting +64k which is odd.

the Spreadsheet for this int16 should be

-32768 to 32767

But I'm getting 0 to 65535

1641999409380.png

is this a bug in v2.73?


Regards

Boysie

cerbo gxModbus TCP
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tnt369 answered ·

This is correct. If you are using int16 this will shown as negative value. But in the list the viewing is as hexadecimal and as unsigned integer (uint16). So the value in the list is approx -20 (65516-65536). Only a thing how the value is interpreted (int/uint).

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tnt369 avatar image tnt369 commented ·

Signed number representations - Wikipedia

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