Originally Posted by
IguSystem
Video BTR is a punched tape connection, i.e. parallel in a way. I used to do those conversions with such cards and later with programmable converters (parallel-serial RS232).
The oldest 3000 and some of the first 5000 series had a punched strip in one direction and RS232 in the other
With a serial port cable and using the TT: method of my post, you can do better. Some 5000 models require RTS/CTS handshake and some handshake from D25 pin number 20. You should be careful if you don't know what you are doing.