Action
Returns a checksum of a string.
Syntax
PRINT Checksum(var)
b = Checksum(var)
b = ChecksumXOR(var)
Remarks
Var |
A string variable. |
B |
A numeric variable that is assigned with the checksum. |
The checksum is computed by counting all the bytes of the string variable.
The checksumXOR is computed by Xor-ing all the bytes of the string variable.
Checksums are often used with serial communication.
The checksum is a byte checksum. The following VB code is equivalent :
Dim Check as Byte
Check = 0
For x = 1 To Len(s$)
Check = check + ASC(mid$(s$,x,1))
Next
The following VB code is equivalent for ChecksumXOR
Dim Check as Byte
Check = 0
For x = 1 To Len(s$)
Check = check XOR ASC(mid$(s$,x,1))
Next
See also
CRC8 , CRC16 , CRC32 , CRC16UNI, CRCMB
Example
$regfile = "m48def.dat" ' specify the used micro
$crystal = 8000000 ' used crystal frequency
$baud = 19200 ' use baud rate
$hwstack = 32 ' default use 32 for the hardware stack
$swstack = 10 ' default use 10 for the SW stack
$framesize = 40 ' default use 40 for the frame space
Config Com1 = Dummy , Synchrone = 0 , Parity = None , Stopbits = 1 , Databits = 8 , Clockpol = 0
Dim S As String * 10 'dim variable
S = "test" 'assign variable
Print Checksum(s) 'print value (192)
End