Sharp MZ-80C (MZ-80K Line, 1979)

I enjoy boxes that hold a motherboard, some sort of data storage, and a CRT in the same case. It's a funky look, it was popular in my preferred pre-IBM era of stuff, and all sorts of interesting systems came in the style. Here's a page about about one of my favories.

The MZ-80C, an upgraded version of the previously-released MZ-80K, is a pretty basic system. You get a keyboard, a tape drive, 48K of RAM, a monochrome green screen, and an exposed system bus out the back. One big enhancement of this model over the 80K is that the keyboard is in staggered QWERTY format, not a perfect grid of keys, which makes typing a bit easier. I'm fairly certain you could only get it in red whereas the 80K came in black, green, red, brown, and maybe even more.

They call this a "Clean Computer" as Sharp didn't actually put an OS in ROM to keep base RAM usage low. You boot into a very simple monitor which lets you do a handful of commands:
LOAD the cassette tape starting from wherever it's at
LOAD[PROGRAM] to have the cassette drive search for and load a program with a particular name
GOTO$[LOCATION] to start a program with a specific entry point
FD to check and load whatever's at location $F000
SG to have the beeper make noise every time you press a key
SS to have the beeper quit making noises when you type

Some alternate monitors exist, for example page has a SP-1002 replacement which gives stuff like the ability to dump memory and restart the system without opening the thing up.

Speaking of opening the system up, the MZ-80 opens kinda like a Commodore PET. Take a few screws out on the bottom of the system - these are probably long gone - and then lift the front up like it's the hood of a car. There's a funky hinging arm on the left side which you can deploy and even a safety screw that blocks the hinge and keeps the system up in case you were to bump anything.

You can see the full 48K of RAM, three 16K banks of 4116s across the bottom. To their left is a little jumper block which needs to be set up for whatever your memory configuration is, just keep it as-is unless you need to upgrade.

Right below the bottom edge of the power supply is your reset switch. Press it and it dumps everything back to the monitor.

Under the connector blocks is your CPU, a Z80A at a whopping 4MHz. You can also see the ROMs to the left of it, a 2K chip for the CGROM and a 4K chip for the monitor.

On the top side of the case, directly attached to the very exposed (and gladly willing to zap you) HV board for the CRT, are the monitor adjustment controls. You've got the usual contrast and brightness, vertical and horizontal hold adjustments, and a focus knob. If you're a klutz like me, use an insulated screwdriver or something plastic to turn these as it's really easy to zap your hand trying to turn these.

I'd write a section about the cassette drive to go here but, at the moment, my drive belt is shot. When I find a good replacement I'll add it here!

I'd also write a section about the MZ-80K SD board to go here, a very useful add-on which just takes breaking out +5V and changing out a ROM, but I don't actually have one soldered together for myself at the moment. Same deal as the tape drive, I'll update this page with info on it later!

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