VeriFone MX800 Series - Page 37

DEVICE DRIVERS
msrRead
M
X
800 SERIES PROGRAMMERS GUIDE 37
The status byte (s1,s2,s3) can have one of the following values:
Return Values
0 valid data
1 no data
2 missing start sentinel or insufficient data
3 missing end sentinel or excessive data
4 missing BCC or BCC error
5 parity error
NOTE
The returned error status may not reflect the exact cause because the algorithm
tries to decode data in both direction streams. An error in one direction stream
may not produce the same error as in the other.
The decode algorithm searches the entire data stream for the start sentinel.
> = 0 Total number of bytes read
< 0 Error