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I am writing my LUA-Code in order to decode a UDP-Payload. I need to read JUST the first 20 bits of the following 3 bytes in a LITTLE-ENDIAN decoding: I tried with the following function: ::subtree:add_le((buffer:range(79, 3):bitfield(0, 20)):le_uint()) But I get this error: ::Lua Error: ...oftware\WiresharkPortable\App\Wireshark\diagnose_118.lua:94: attempt to index a number value

The bytes seen in the payload of the UDP-Message may be the following:

BIG-ENDIAN -->FF 35 50 LITTLE-ENDIAN -->50 35 FF The hexadecimal-data interesting for me is --> 0 35 FF --> 0000 0011 0101 1111 1111

The problem appears when I introduce the function bitfield - I cannot avoid it as I just want the first 20 bits and not the whole 24. Do you know another different way to fulfill my purpose? Many thanks in advance! :)

I am writing my LUA-Code in order to decode a UDP-Payload. I need to read JUST the first 20 bits of the following 3 bytes in a LITTLE-ENDIAN decoding: I tried with the following function: ::subtree:add_le((buffer:range(79, 3):bitfield(0, 20)):le_uint()) 20)):le_uint()) But I get this error: error:

::Lua Error: ...oftware\WiresharkPortable\App\Wireshark\diagnose_118.lua:94: attempt to index a number value

The bytes seen in the payload of the UDP-Message may be the following:

BIG-ENDIAN -->FF 35 50 50
LITTLE-ENDIAN -->50 35 FF
The hexadecimal-data interesting for me is --> 0 35 FF --> 0000 0011 0101 1111 1111

The problem appears when I introduce the function bitfield - I cannot avoid it as I just want the first 20 bits and not the whole 24. Do you know another different way to fulfill my purpose? Many thanks in advance! :)