Chapter 6 computer interface – INFICON SID-142 Thin Film Deposition Controller User Manual
Page 68
Chapter 6 Computer Interface
6-3
Update Command:
@<command>;<param1>;...;<paramn>;<data>;<Chksum><CR>
Update Example: Set Process
@UP;11;MyProcess;44<CR>
Description:
@;UP;
Update Process command
;
Separator
01
Parameter 01 (Set Process)
;
Separator
MyProcess
Data
;
Separator
??
Checksum
<CR>
Carriage Return (ASCII 13)
Response Example: Set Process Completed
@UP;<ACQ>;??<CR>
Response Example: Set Process Failed
@UP;<NAK>;<ERR>;??<CR>
(Response to Update Process)
ERR: 01
Illegal Command
02
Illegal Parameter
03
Illegal Format
04
Checksum Error
05
Request Denied
06
Unknown Error
Checksum Calculation
The sample code below calculates the FCS checksum of a string of characters.
In the code, Message is a string that has been stripped of terminator and
checksum characters before being passed to this routine
' XOR ASCII codes
For i = 1 To Len(Message)
FCS = Asc(Mid$(Message, i, 1)) Xor FCS
Next i
' Convert FCS to two character hex string
If Len(Hex$(FCS)) = 1 Then
CalcChkSum = "0" & Hex$(FCS)
Else
CalcChkSum = Hex$(FCS)