On Mon, Jan 30, 2023 at 5:34 PM Jim Brain via cctalk <[email protected]> wrote: > > On 1/30/2023 11:14 AM, Chris via cctalk wrote: > > It had a dedicated cassette port? Don't most cassette ports resemble a > > serial port, or is my wonky brain making that up? What protocols did most > > cassette ports use (c64/128?, IBM 5150, coco ...)? > > Lots of systems had dedicated cassette ports, but yes, CoCo has a > dedicated cassette port, as does all the 8 bit CBM machines, I think the > Model 1/3/4 also, and doesn't the Apple II have one as well.
Yes, all those have dedicated cassette ports. > I am sure > I am forgetting a bunch. ZX80, ZX81, Spectrum, Acorn Acom, Acorn Electron, BBC Micro, etc, etc. Do you count machines like the Amstrad CPC464 which had a built-in cassette recorder? > > I think it would have been hard to have the cassette use the serial > port, because cassette needs audio tones, not RS232 levels. There was an almghty kludge in the TRS-80 Modem 1. You could flip a switch and the modem serial input changed from RS232 levels to cassette levels. The modem serial output became a keyed (by the serial data) audio tone. This meant you could link it to a Model 1 cassette port and drive it with special software. It's documented in the service manual for said modem. -tony
