MagTek HALF CARD PORT - Manual (Page 23)

Section 3. Commands, Formats, Timing
15
READER TO HOST FORMATS
The following diagram represents the format of the data transmitted to the Host:
Where optional characters
STX (0x02) = Start of text character
ESC (0x1B) = Escape character
CR (0x0D) = Carriage return character
ETX (0x03) = End of Text
are used to frame data.
These sentinel characters can be changed in the new reader by using the program mode
command set.
% = Start Sentinel Track 1
; = Start Sentinel Track 2
? = End Sentinel
The LRC character is not transmitted.
Track data may be represented as follows:
Where
SS = Start Sentinel: "%" for Track 1; ";" for Track 2
Data = Track Data in track order that is, Track 1 then Track 2
ES = End Sentinel: "?"
Sensor = "0" no card in reader
"1" card present in reader (rear sensor blocked)
If there is an error in one of the tracks, the "Track Data" field will be replaced with "E" (0x45).
SS Track Data ES Card Sensor Status
STX ESC % Track 1 Data ? ; Track 2 Data ? Sensor CR ETX
Optional