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How to save in a variable a specific value from masked bytes?

The variable YEAR, has got an offset of 2000. This means, that I need to add 2000 to the taken value. Here I create my "ProtoField":

local Year_proto = ProtoField.uint16("Variable_Year", "This is the transmitted year", base.DEC, nil)

Before adding it to the shown values of my Wireshark-Parser, I need to save the LITTLE-ENDIAN 7 bits long number. The bit mask should be 0x07f0 = 0000 0111 1111 0000 - so the only intersting bits here are the "1". The start byte is the 77 and the information is found in two bytes (buffer(77,2).

Can you please tell me how can I save the mentioned LITTLE-ENDIAN 7 bits number? Let's say that the name of the saved number is saved in "year_test" and the variable "year" is the corrected value:

offset=2000.0
year=year_test+offset //for example year_test=0x15=21 --> 2021

Afterwards I would list the corrected year value as follows:

subtree:add(Year_proto, year)

Many thanks for your help!

How to save in a variable a specific value from masked bytes?

The variable YEAR, has got an offset of 2000. This means, that I need to add 2000 to the taken value. Here I create my "ProtoField":

local Year_proto = ProtoField.uint16("Variable_Year", "This is the transmitted year", base.DEC, nil)

Before adding it to the shown values of my Wireshark-Parser, I need to save the LITTLE-ENDIAN 7 bits long number. The bit mask should be 0x07f0 = 0000 0111 1111 0000 - so the only intersting bits here are the "1". 0000. The start byte is the 77 and the information is found in two bytes (buffer(77,2).

Can you please tell me how can I save the mentioned LITTLE-ENDIAN 7 bits number? Let's say that the name of the saved number is saved in "year_test" and the variable "year" is the corrected value:

offset=2000.0
year=year_test+offset //for example year_test=0x15=21 --> 2021

Afterwards I would list the corrected year value as follows:

subtree:add(Year_proto, year)

Many thanks for your help!

How to save in a variable a specific value from masked bytes?

The variable YEAR, has got an offset of 2000. This means, that I need to add 2000 to the taken value. Here I create my "ProtoField":value:

local Year_proto = ProtoField.uint16("Variable_Year", "This is the transmitted year", base.DEC, nil)

Before adding it to the shown values of my Wireshark-Parser, I need to save the LITTLE-ENDIAN 7 bits long number. The bit mask should be 0x07f0 = 0000 0111 1111 0000. The start byte is the 77 (buffer(77,2).

Can you please tell me how can I save the mentioned LITTLE-ENDIAN 7 bits number? Let's say that the name of the saved number is saved in "year_test" year_test and the variable "year" is the corrected value:

offset=2000.0
year=year_test+offset //for example year_test=0x15=21 --> 2021

Afterwards I would list the corrected year value as follows:

subtree:add(Year_proto, year)

Many thanks for your help!

How to save in a variable a specific value from masked bytes?bytes

The variable YEAR, has got an offset of 2000. This means, that I need to add 2000 to the taken value:

local Year_proto = ProtoField.uint16("Variable_Year", "This is the transmitted year", base.DEC, nil)

Before adding it to the shown values of my Wireshark-Parser, I need to save the LITTLE-ENDIAN 7 bits long number. The bit mask should be 0x07f0 = 0000 0111 1111 0000. The start byte is the 77 (buffer(77,2).

Can you please tell me how can I save the mentioned LITTLE-ENDIAN 7 bits number? Let's say that the name of the saved number is year_test and the variable "year" is the corrected value:

offset=2000.0
year=year_test+offset //for example year_test=0x15=21 --> 2021

Afterwards I would list the corrected year value as follows:

subtree:add(Year_proto, year)

Many thanks for your help!

How to save in a variable a specific value from masked bytes

The variable YEAR, has got an offset of 2000. This means, that I need to add 2000 to the taken value:

local Year_proto = ProtoField.uint16("Variable_Year", "This is the transmitted year", base.DEC, nil)

Before adding it to the shown values of my Wireshark-Parser, I need to save the LITTLE-ENDIAN 7 bits long number. The bit mask should be 0x07f0 = 0000 0111 1111 0000. The start byte is the 77 (buffer(77,2).

Can you please tell me how can I save the mentioned LITTLE-ENDIAN 7 bits number? Let's say that the name of the saved number is year_test and the variable "year" is the corrected value:

offset=2000.0
year=year_test+offset //for example year_test=0x15=21 --> 2021

Afterwards I would list the corrected year value as follows:

subtree:add(Year_proto, year)

Many thanks for your help!