Hi, I'm alive, for those of you who remember me from IRC. Sorry for my absence from efnet for the last year or so; either efnet has my VPS's IP range blocked, or my VPS host has efnet blocked. And I've been using my VPS as a VPN tunnel. But anyway...
I recently came into possession of an Epson PC-486GR - an NEC PC-9801 series clone from 1992. I got it in part so I could help a friend of mine dive into and embrace a passion for old electronics/computers, something I've been swimming in for a long time but which they felt was out of their reach before they met me. This friend was already determined to get a PC-98, and I decided that 1) I would enjoy learning about it, too, and 2) that it'd be fun for me to get one so we could learn about it together, since I had considerably more pre-existing knowledge about DOS and SCSI and other "old computer things" than they did.
My blog post/writeup:
https://wyatt8740.gitlab.io/site/blog/011_012.html#pc9801-1
![Image]()
(Click image for full size.)
I've been working on writing a huge documentation blog post about it, and I thought that maybe some people here would find useful or interesting, even if it's mostly not programming oriented as of now.
It's not specifically about developing for it for the most part. It is more of a general description of the various bits of hardware, how they interact, some pinouts, and more generally a guide on what you're in for if you try to get one of these and set it up in the western world in $year. For that reason, I'm not sure if it strictly counts as something that I could post in "Other Retro Dev." If you think it'd be fine there, admins, then please feel free to move it.
Also, if anyone has corrections or disagreements regarding something I've said, please let me know why I'm wrong. I'll try to fix it if your argument seems reasonable/credible. I'm definitely not perfect, and a lot of you guys might know more than I do about this stuff. Part of my reason for posting here is because I'd like your input/suggestions. I was maybe 14 when I first interacted with nesdev, and am 28 now, but I am still probably a fair way behind some of you guys.
If there's something I should talk about more, clarify, or rearrange on the page for legibility/comprehension, then I also welcome those kinds of critiques. This is my attempt to improve the somewhat poor and spotty amount of documentation on the PC-98 series in the English language - especially for the Epson clones, but for NEC machines as well.
Anyway, TL;DR - what do you guys think of it so far? Is it helpful? How can I make it better? What do I need to talk about more? Can't promise to do everything that's suggested, but I really do want to make this helpful for people beyond just myself.
If you like it and don't have much more to say, I also appreciate that input to know I'm doing something right.
Again, that link is:
https://wyatt8740.gitlab.io/site/blog/011_012.html#pc9801-1
--------
Oh yeah; I wanted to also take a moment to reply to rainwarrior's statement about two years ago without bumping that thread, so here it goes:
My PAL A500 is also roughly 1:1, to confirm that. At least with my Amiga's Commodore 1942 monitor (when it works... so many bad capacitors).
From what I can tell, PC-88's mostly used the same 24KHz scan rate as the PC-98's used until pretty late in their lifetimes. And my monitor was intended for the PC-8801mkIISR, but is still compatible with my Epson PC-98 clone from the early 90's.
I recently came into possession of an Epson PC-486GR - an NEC PC-9801 series clone from 1992. I got it in part so I could help a friend of mine dive into and embrace a passion for old electronics/computers, something I've been swimming in for a long time but which they felt was out of their reach before they met me. This friend was already determined to get a PC-98, and I decided that 1) I would enjoy learning about it, too, and 2) that it'd be fun for me to get one so we could learn about it together, since I had considerably more pre-existing knowledge about DOS and SCSI and other "old computer things" than they did.
My blog post/writeup:
https://wyatt8740.gitlab.io/site/blog/011_012.html#pc9801-1
(Click image for full size.)
I've been working on writing a huge documentation blog post about it, and I thought that maybe some people here would find useful or interesting, even if it's mostly not programming oriented as of now.
It's not specifically about developing for it for the most part. It is more of a general description of the various bits of hardware, how they interact, some pinouts, and more generally a guide on what you're in for if you try to get one of these and set it up in the western world in $year. For that reason, I'm not sure if it strictly counts as something that I could post in "Other Retro Dev." If you think it'd be fine there, admins, then please feel free to move it.
Also, if anyone has corrections or disagreements regarding something I've said, please let me know why I'm wrong. I'll try to fix it if your argument seems reasonable/credible. I'm definitely not perfect, and a lot of you guys might know more than I do about this stuff. Part of my reason for posting here is because I'd like your input/suggestions. I was maybe 14 when I first interacted with nesdev, and am 28 now, but I am still probably a fair way behind some of you guys.
If there's something I should talk about more, clarify, or rearrange on the page for legibility/comprehension, then I also welcome those kinds of critiques. This is my attempt to improve the somewhat poor and spotty amount of documentation on the PC-98 series in the English language - especially for the Epson clones, but for NEC machines as well.
Anyway, TL;DR - what do you guys think of it so far? Is it helpful? How can I make it better? What do I need to talk about more? Can't promise to do everything that's suggested, but I really do want to make this helpful for people beyond just myself.
If you like it and don't have much more to say, I also appreciate that input to know I'm doing something right.
Again, that link is:
https://wyatt8740.gitlab.io/site/blog/011_012.html#pc9801-1
--------
Oh yeah; I wanted to also take a moment to reply to rainwarrior's statement about two years ago without bumping that thread, so here it goes:
I guess they might not be quite 1:1 on non-LCD/plasma models, but it should at least be noted that my PC-98's monitor (NEC PC-KD851) does draw a roughly 8:5 raster for the 640x400 picture being generated by the GDC (µPD7220 or evolution thereof) - which is therefore about a 1:1 PAR. It seems my monitor purposefully underscans to maintain a relatively square PAR instead of trying to fill the entire screen.Maybe PAL Amiga, or PC88 (sometimes) had close to 1:1? I think you could make a case that some european SNES developers might have worked with 1:1 PAR in D-Paint on the Amiga. PC88 was less suitable for colourful artwork (and had inconsistent PAR)... the later PC98 which a lot of Japanese developers were using through the SNES era didn't have 1:1 PAR on most models.
My PAL A500 is also roughly 1:1, to confirm that. At least with my Amiga's Commodore 1942 monitor (when it works... so many bad capacitors).
From what I can tell, PC-88's mostly used the same 24KHz scan rate as the PC-98's used until pretty late in their lifetimes. And my monitor was intended for the PC-8801mkIISR, but is still compatible with my Epson PC-98 clone from the early 90's.
Statistics: Posted by wyatt8740 — Tue Jan 16, 2024 3:51 pm — Replies 4 — Views 283