Minstrel the 4th is a modern recreation of the Jupiter Ace, a lesser-known home computer from 1982. It's notable for its use of Forth rather than BASIC which was common at the time.
The Ace had a ZX Spectrum-like rubber keyboard. The Minstrel's is an improvement but its small tactile switches don't really allow for fast typing.
It's not only the size and arrangement of the keys that limit typing speed, but the fact that the keyboard matrix is scanned every 1/50th second and then not buffered. So even with modern key switches, this makes typing on computers like the Ace, ZX81 and Spectrum is a bit of a plod. It's easy for the Pico to buffer the keyboard input, and present it to the Minstrel one key at a time, at a speed that it can handle.
This also opens up the possibility of connecting a serial terminal to the device to allow listings to be pasted to the Minstrel. It also means that anything you type using a USB keyboard can be echoed to the terminal giving you a paper tape of In the top picture you can see that the finished product has a USB-FTDI adaptor attached for this purpose.
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