Issues reading card reader w/ Arduino

Development Boards Arduino
1

Hello, I am attempting to read this card reader with my Arduino’s serial monitor: http://www.sparkfun.com/products/11096

All I get is garbled text when I swipe a card. Each string is always the same for each card, but not the same as other cards.

I have the unit powered and the data pins broken out, I just can’t figure out why the signal isn’t readable text. At first I thought it was because the signals are output from the reader at 3.3V. I tried running the signal through a hex inverter twice to step it up to 5V, but I get the exact same garbage with or without the hex inverter.

Any suggestions? Or questions I can answer to help you help me?

Regards,

Steve

2

The specs for your reader say it’s not 5V nor 3.3V but RS232, meaning -12/12V. Using an Arduino to read these signals requires some sort of MAX232 or the like to change the levels. In your text you just mention Arduino’s serial monitor. Do you mean the serial monitor of the Arduino IDE? Please describe your wiring because you seem to mix different things…

Often getting garbled text means having the wrong baud rate. Did you check that you have chosen 9600/8/N/1?

3

Also remember RS-232 is inverted from TTL, which could explain the garbled text.