C64 to RS232 Interface

 Userport C64                                           C64 RS232
                       _________
                      |         |
   PA2 M-----------11-|         |-14------------------- TXD (2)
   PB1 D-----------10-|         |--7------------------- RTS (4)
   PB6 K-----------12-| MAX 232 |-13------------------- CTS (5)
 FLAG2 B---X--------9-|         |--8------------------- RXD (3)
   PB0 C---|          |         |--3--|+-|
   VCC 2-----------16-|         |--1-----|              DB25-connector
   GND N------X----15-|         |
              X--|+-2-|         |--5--|+-|
              X--+|-6-|_________|--4-----|
              |
              |---------------------------------------- GND (7)

-|+- capacitor 22uF/16V
-  +

Contributions

• Joakim Ögren

Sources

• Usenet posting in comp.sys.cbm, C64 -> Serial -> IBM ? by Andreas Boose