Maybe IBM did not add it in the first place, because of that feature that would defeat their big line-up of mainframes at the time.
But someone knowing someone there at IBM may be able to add something or tweak that computer, so still it is not the original design of either one of those computers.
And it was not sold in the marketplace!
And, perhaps, JT just needed the computer also, instead of just relying on manuals because they might want to know how it was built, and disassembly that computer, so something similiar they could build to actually do the job they needed the computer for, and really not use the computer that was picked up.
If you wanted to know how the Apple IIC computer was made -- you may use reference manuals if you can get ahold of them, or actually have the computer on hand, to measure and actually know how the computer was built, but not use it in the end, but a similiar design made in the future to do some task.
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