Am I right in assuming the serial interface on the pi is TTL and not RS232?
I have a mifare reader below that is stated to work at 5v and 3.3v but it has an RS232 interface.
I have writted some python to read, format and return the UID of some cards. It is currently connected to a usb to serial converter and works fine.
Next step is I want to get this working directly from the pi. How do I interface this?
I measured the voltage across Ground and TX on the reader and it is -7.25v and goes to -6.88v when I present a badge.
Anyone got suggestions I don't want to damage my pi by prematurely connecting a device to it when I don't fully understand the circuitry.
Cheers in advance
Oh also here is the datasheet of the reader. Not sure what the "out 1" and "out 2" pins do or the "RST".
http://www.ehuoyan.com/download/module/ ... G++_EN.pdf