Command – Measurement Computing CB-COM-7021 User Manual
Page 26
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CB-7021, CB-7022, CB-7024 User’s Manual
2. Command
Command Format: (Leading)(Address)(Command)[CHK](cr)
Response Format: (Leading)(Address)(Data)[CHK](cr)
[CHK]
2-character checksum
(cr)
end-of-command character, character returns(0x0D)
Calculate Checksum:
1.
Calculate ASCII sum of all characters of command (or
response) string except the character returns(cr).
2.
Mask the sum of string with 0ffh.
Example:
Command string: $012(cr)
Sum of string = ‘$’+‘0’+‘1’+‘2’ = 24h+30h+31h+32h = B7h
The checksum is B7h, and [CHK] = “B7”
Command string with checksum: $012B7(cr)
Response string: !01300600(cr)
Sum of string: ‘!’+‘0’+‘1’+‘3’+‘0’+‘0’+‘6’+‘0’+‘0’
= 21h+30h+31h+33h+30h+30h+36h+30h+30h = 1ABh
The checksum is ABh, and [CHK] = “AB”
Response string with checksum: !01300600AB(cr)
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