This port seems to be configured to send TTL logic signals to a chip-card (smartdcard) reader. The RX/TX lines are high logic (+5V) while inactive. They transition to 0V when bits are being moved. This is inverted from RS232 and the wrong signal levels. A MAX232 could be used to invert and condition these signals so you could use a modem or such. On the other hand this port would be perfect for talking to a PIC1684, serial A/D, 4-line LCD, or other TTL serial device with no conditioning. The best use might be as a DSS emulator/programmer. The port will interface to the DSS plastic through a $2.50 socket and a $3.00 3.579MHZ oscillator with no PC bord required. Stick the socket and oscillator on a perfboard, hook up RX/TX and RTS plus the clock from the ocsillator and +5V/0V all available at CN26 on the Scovery. Mount it to the lugs behind the chipcard slot and viola, phoenix programmer! Run the SLE44 stuff from Comm1 and it would make a neatly packaged DSS H-card emulator.
-bruce | |
