The Mysterious Sharp MZ-100

[BikeForever]

Again with the undying zombie thread
Hey @Retroplayer , that's some usful info for me, I just got my 4502. I'm wanting to upgrade my memory from 380k. Could you tell me the part number on your memory chips please?
Also I'm wondering is an ISA graphics card could be fitted? Seems unlikely, but it would be neat if a vga card just slotted in.

 

[Franchute13]

Well, at least I am not resurrecting a too old discussion. I actually bought a PC-4502 system about a month ago and have been exploring it since. I managed to get a XT-CF card working internally on the CN14 header. For now, it is just bodged wires to an 8-bit ISA connector. Routed PCB coming soon.

At the moment, it recognizes the drive (tested from 32MB to 512MB) and I can read and write to it. Having trouble booting from it, but that is most likely just some config changes I need to make to the XT-CF Bios.

Prior to this, I got a GOtek drive running as the A drive. Kept the original 720K B drive.

All of the expansion connectors inside are sub-sets of the ISA bus.

I am planning several other upgrades to it as well. One will be a dual serial card with a battery backed RTC. Another is a mega card with a joystick port, sound card, EMS, and an 8255 GPIO.

So far, it looks like all of these different Sharp computers from this era use the same connectors.

Hi.
Thanks for the effort.
Any updates on your HDD addition project?

 

[Retroplayer]

Hi.
Thanks for the effort.
Any updates on your HDD addition project?

No update. It just worked. Including booting. I don't remember what that was , but I am pretty sure it was just configuration of the bios.

I did not finish the board to plug directly in, though. It is still dangling on wires.

I even managed to get Windows 3.0 running (terribly) on it.

I encountered someone that had made an ISA expander that plugs into the expansion port in the back. Fun for some development, but not great having something hanging off the back.

Sharp PC-4600 (PC-4602/PC-4641) Expansion Bus ISA Breakout

This project provides two 8-bit ISA Slots to the Sharp PC-4600 (PC-4602/PC-4641) laptop computer systems.

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