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Epson PX-4

The Epson PX-4; beautiful, isn't it?
[Epson PX-4][Batteries]

6V DC in.
4 x 1.2V/500mAH Ni-cad pack
4.8V /50mAh Ni-cad
Production year: 0000OS: CP/M
Type: LaptopRAM: 64KB
ROM: 32KBDisplay: Internal LCDResolution: 40 x 8chars
The Epson PX-4

So, what's this then? Produced in 1985, it looks superficially like the older HX-20, but when you start looking, there's a few differences.


Upper Right corner: 30pins(2x15) for a small printer or other module. Possibly even a RAM or ROM pack.
Lefthand side: A RAM Disk can be connected on the expansion bus. Se separate page.
B: and C: drives. these are slots for ROM modules beneath the machine.

Other details that you will notice is that the screen is hinged, there are small feet in the back of the machine to give it a tilt, the keyboard can easily be removed just by removing 3 screws(No cable, just a pressure based connector), and that this machine have a VERY recessed RESET switch.
The mini printer have a 8049 microcontroller and a 2KB ROM. That is NOT usual in these types. They are usually just 'dumb' interfaces that the computer must control by itself. What made the designers decide on stuffing a dedicated processor in the printer? (Not that I'm complaining. :-)

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