Actually in the late 70's early 80's I ordered parts from GM/GMPD using a thermal heat print terminal/computer terminal. With a keyboard and a dual cassette deck on top I would communicate with our inventory control service provider, Reynolds and Reynolds. I would run a routine from that terminal to generate a stock order, get the results, and record them on a cassette, they looked like the common cassette. From there I flipped a series of toggle switches and typed in a phone number to GMPD's computer and their computer communicated with my terminal and read the cassette. The response of their computer was sent back and recorded on the other cassette on my terminal. And finally my terminal read the cassette and answer from GMPD and printed the results on that terminals thermal heat print paper.