How to calculate checksum?

Posted by Patel Rikin on Super User See other posts from Super User or by Patel Rikin
Published on 2012-06-11T04:16:47Z Indexed on 2012/06/11 4:42 UTC
Read the original article Hit count: 983

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checksum

I m developing instrument driver and i want to know how to calculate checksum of frame.

Explanation:

Expressed by characters [0-9] and [A-F].

Characters beginning from the character after [STX] and until [ETB] or [ETX] (including [ETB] or [ETX]) are added in binary.

The 2-digit numbers, which represent the least significant 8 bits in hexadecimal code, are converted to ASCII characters [0-9] and [A-F].

The most significant digit is stored in CHK1 and the least significant digit in CHK2.

This is sample frame :

<STX>2Q|1|2^1||||20011001153000<CR><ETX><CHK1><CHK2><CR><LF>

and i want to know what is value of chk1 and chk2 and i am new in this so i m totally blank about how to calculate checksum

i am not getting above 3rd and 4th point.

can any one provide sample code for c#.

Please help me.

© Super User or respective owner

How to calculate checksum?

Posted by Patel Rikin on Programmers See other posts from Programmers or by Patel Rikin
Published on 2012-06-11T04:18:51Z Indexed on 2012/06/11 4:46 UTC
Read the original article Hit count: 983

Filed under:

algorithms

I m developing instrument driver and i want to know how to calculate checksum of frame.

Explanation:

Expressed by characters [0-9] and [A-F].

Characters beginning from the character after [STX] and until [ETB] or [ETX] (including [ETB] or [ETX]) are added in binary.

The 2-digit numbers, which represent the least significant 8 bits in hexadecimal code, are converted to ASCII characters [0-9] and [A-F].

The most significant digit is stored in CHK1 and the least significant digit in CHK2.

This is sample frame :

<STX>2Q|1|2^1||||20011001153000<CR><ETX><CHK1><CHK2><CR><LF>

and i want to know what is value of chk1 and chk2 and i am new in this so i m totally blank about how to calculate checksum

i am not getting above 3rd and 4th point.

can any one provide sample code for c#.

Please help me.

© Programmers or respective owner

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