Searching for NEC PC-8001A software & hardware

[jltursan]

Samdisk also has a good support to write D88 image disks to physical floppy drives, have you tried just using it alone?

Btw, L3diskex has evolved great, now it supports a hell of formats (altough is still missing something, of course...)

 

[1980s_john]

The color sockets were quite odd. These socket has:

V sync = 60Hz negative going pulses (16.7ms between pulses, TTL levels, 0V to 4.1V)
H sync = 15.75kHz negative going pulses (63us between pulses, TTL levels, 0V to 4.1V)
Color clock = 14.3MHz (ie 4 times the NTSC 3.579545MHz color carrier), positive going pulses (70ns between pulses, from -2V to +8V)
RGB = waveform going from -8V to +16V (24V p-p)

As the power on screen is mostly blank the RGB signals are long periods of 0V with short bursts of signal. Not sure why the voltage goes over such a large range, maybe it is designed for some sort of terminating network (eg a 1kohm resistor in series feeding a 100 ohm resistor to ground would give 2V p-p, or a 150 ohm resistor in series feeding a 75ohm input)?
<cut>

I would be wary of connecting the color output straight into a prized multisync monitor without checking it out first.

Hi,
10 years on I finally got my PC-8001 outputing RGB into my recently repaired NEC Multisync II (JC-1401). Looking at this monitors RGB inputs each pin is clamped by diodes between ground and 8V so I tried directly wiring the RGB output into the monitors RGB input (using CGA pinouts). The (eventually) simple cable (*) is as follows:

8-pin DIN 9-pin D-type
2 --- ground ----- 1 & 2
6 --- red ---------- 3
7 --- green -------- 4
8 --- blue ---------- 5
4 --- Hsync -------- 8
5 --- Vsync -------- 9

I didn't need to connect up the Intensity line (CGA pin 6). Video looks good but just in white (ie RGB all on).

I'd like a short test program to check the 8 available colours, I tried a PC-8801 one-liner:

FOR I=0 TO 7:LINE(I*10,150)-(I*10+9,180),I,BF:NEXT

(as shown here - https://www.leadedsolder.com/2018/09/24/pc88-colour-video.html )
but this isn't valid on the PC-8001. What's the simplest test program please?

Regards,
John
(*) I actually built an adapter in a small plastic box for maximum flexibility, and used a straight 8-pin DIN to 8-pin DIN lead, plus a straight 9-pin D-type to 9-pin D-type. The latter is needed on the Multisync II as a CGA cable (and I use it with a VGA to CGA adapter lead for VGA).

 

[seat safety switch]

For colour in my own (upcoming; as soon as the PC-8033 clone board and PC-80S31 get here) PC-8001 post, I have the following:

10 CONSOLE ,,,1
20 FOR I = 0 TO 8
30 COLOR I
40 PRINT "Colour", I
50 NEXT I

Produced this on my cheap 150-ohm adapter for my MultiSync 1970NX, but the multi-digital-RGBI adapter PCB I cobbled together for my MultiSync 3D hasn't arrived yet either.

 

[1980s_john]

Thanks - here's the result attached. All looking good, thanks for earlier page from the manual confirming the colours.

BTW I found the best settings on the Multisync II are:

Manual mode = ON
Mode = Color
Color Mode = 8

Setting Color Mode =8 disables the Intensity input, before switching I had Manual mode=OFF and had to turn the brightness up.

I'm still hoping for a simple program to draw colour bars, does the N-BASIC allow this?

Any news on a scan of the English N-BASIC manual please? I know this is a big job, so maybe get a tip jar started!

Regards,
John

 

[seat safety switch]

Sorry about the broken image in my previous post, apparently copying and pasting the image into the forum post actually tries to put in a localhost URL, as opposed to "attach files..."



Your colours are a little different from mine, but the MultiSync II is coming up with its own palette I guess?

 

[1980s_john]

Thanks for uploading your screen shot. In the flesh the colours on my Multisync II look bright and clear, my photo doesn't do the monitor justice.

What's the N-BASIC command to switch to 80 columns please, assuming this is possible on a base level 16K machine with no add-ons?

BTW I now have a spare PC-8001BE for sale (can post from UK at usual rates - nb its heavy), if interested please PM with any offers before I put it on eBay (I will list at £199 so offers from £150 please).
Regards,
John

 

[1980s_john]

Hi,
I found the N-Basic reference card (in Japanese) here:

NBASIC Refcard : Free Download, Borrow, and Streaming : Internet Archive

N BASIC Reference Card (NEC) PC-8001

archive.org

From this the command to change screen to 80 columns / 25 rows is:

WIDTH 80.25

and back to 40 columns / 20 rows:

WIDTH 40,20

As a starter please can someone scan the English ref card (about 4 or 6 pages at most)? I can stich them together as needed if that would help.

Regards,
John

 

[Ksinfos]

Hi,
I'd like to share this manual with you, which I scanned.

PC8001-B NBASIC Reference Manual

Regards,
Carl

 

[1980s_john]

I did a quick search and I found some info on setting the PC-8011 modes here on Enri's website. It's in Japanese, but Google Translate does a reasonable job of it.

Mode 2 looks like the way to go for a full 64K, but he cautions:

Not sure how that squares with CP/M. He also has a good page on the PC-80s31 disk unit, but I haven't read it yet. There is also the possibility of building this internal 32K board made by one of the Japanese hobbyists, but I'm not sure how CP/M wants to see the address space and/or ROMs.

Also in Enri's page it says the memory map mode can be set through the I/O port as follows:

0E0H : Mode 0
0E1H : Mode 1
0E2H : Mode 2
0E3H : Mode 3

So I am guessing when CP/M boots up it writes to 0E2H to set Mode 2.

I noticed on JCM's PC-8001 video (

) that the CP/M boot screen shows:

56K CP/M

He was using a PC-8012 rather than PC-8011 but I'm not sure whether the 32K RAM extension is different.

Regards,

John

 

[Ksinfos]

Hi all,
As soon as I have a little time, I'm going to digitize these books...


Carl

 

[1980s_john]

But since you seem to have the ability to dump the ROMs in your PC-8001A, I'd love to get a copy of them so I could compare them with the Japanese versions. I'm not sure if I can receive PMs in this forum (I know I can't send them), so it's probaby best to use my e-mail address from my GitHub profile.

Hi,
I've finally dumped the three 2364 ROMs and the character generator EPROM (2716) from my PC-8001BE. I haven't done a compare but I expect the ROMs are same as PC-8001A, the character ROM will be different as machine doesn't display # but displays £ instead. So for double length floating point need to define as A£=1.23456789012345

Hopefully these are good dumps, I'll message CJS as requested.
Regards,
John
PS Hardest part was removing the metal screening cover. Although only held in by the 4 feet screws it wouldn't come off until I levered it, there was a tiny bit of corrosion sticking it to the metal base mounting. All very clean inside so no issue, and PSU dated 1983-7 so a late model.

 

[seat safety switch]

The 80S31 finally arrived along with some other goodies to help with the shipping cost. Zenmarket double-boxed it and put styrofoam reinforcements on the corners, stuffed the voids with bubble wrap, and even cut a custom cardboard jig for holding the eject levers still so they wouldn't get sheared off if everything else failed and the drive still somehow moved around in the box.

Pretty good packaging for a ¥1000 fee.



I'm in the midst of digging out parts and building cables for the PC-8033 clone. Things will be slow over the holidays!

 

[Ksinfos]

Hi,
Enjoy your reading


https://drive.google.com/file/d/1c8n7-KZAeTI1EgVEHBjeB2aUfqR-UTwC/view?usp=drive_link


https://drive.google.com/file/d/1jwQXqSxHCrdeukVgk77lDxesF4LpwwnU/view?usp=drive_link

NEC PC8031-8032 Mini Disk Unit Reference Manual .pdf

drive.google.com

Carl

 

[1980s_john]

Hi,
Here are some books with type-in programs for the PC-8001. Books are in Japanese but all listings are in English:

PC-8001 はるみのプログラミングレッスン : Free Download, Borrow, and Streaming : Internet Archive

For NEC PC-8001(N-BASIC)Programming manual for beginners

archive.org

PC 8001 BASIC ゲームブック : アスキー・ラボラトリーズ : Free Download, Borrow, and Streaming : Internet Archive

本書には， グラフィックJ栄作性の優れたPC-8001 の機能を100 % 活用するためのテクニックが秘められています....

archive.org

Following has a tutorial section with step-by-step small type-in programs:

PC 8001活用研究 : Kogakusha : Free Download, Borrow, and Streaming : Internet Archive

Application note for NEC PC-8001. Selection of articles for PC-8001 in magazine I/O.

archive.org

Regards,
John

 

[1980s_john]

Hi,
Enjoy your reading

Many thanks Carl, these are essential reading for any PC-8001 owner (who can't read the Japanese manuals).

Has any one managed to run the disk version of N-Basic? This needs a boot disk (single sided for PC-8032).

Regards,
John

 

[cjs]

Enjoy your reading

Brilliant; thanks for those scans! Are you also going to put them up on archive.org? If not, I'll upload them (unless you object to them being there). That's the place I usually go to search for stuff like this.

 

[cjs]

I've finally dumped the three 2364 ROMs and the character generator EPROM (2716) from my PC-8001BE. I haven't done a compare but I expect the ROMs are same as PC-8001A, the character ROM will be different as machine doesn't display # but displays £ instead.

Thanks for contacting me through Discord; I would have missed this otherwise. I've added your dumps to the repo. It turns out that there is a very slight difference between your BE ROM and the version 1.1 Japanese ROM (a few backslash/yen characters replaced with dollar signs); I'll be sure to include a note about this in my disassembly, if I ever get around to doing more on it.

 

[cjs]

Enjoy your reading

Brilliant; thanks for those scans! Are you also going to put them up on archive.org? If not, I'll upload them (unless you object to them being there). That's the place I usually go to search for stuff like this.

I'll take silence as a "yes." : - ) These manuals are now archived and browsable on-line:
https://archive.org/details/pc-8001b-micro-computer-users-manual-nec-en-1981
https://archive.org/details/pc-8001b-n-basic-reference-manual-nec-en-1981
https://archive.org/details/pc-8031b-32b-mini-disk-unit-reference-manual-nec-en

Looking through them, I noticed that for the Micro Computer User's Manual pages 34-35 are missing. It would be nice to get an update with those added, if it's not too much trouble.

 

[voidstar78]

Great compilation of PC-8001 here! I just recently got a working Japanese PC-8001 with its original color screen. What a neat system and from 1979, wow!

From the PC-8001B manual are these part numbers:

PC-8001 Computer (32K RAM, N-BASIC)
PC-8012 Expansion Unit
PC-8023 132-Character Dot Matrix Printer
PC-8033 I/O Port for PC-8031
PC-8031 Dual Mini-Disk Unit
PC-8032 Expansion Dual Mini-Disk Unit
PC-8041 12" Green Display
PC-8043 12" Color Display
PC-8062 RS-232 Cable
PC-8093 Cassette Port Cable

By "Mini-Disk" that is referring to 5.25" instead of 8", correct? Excellent to think of those 5.25" as the mini-disk!


Has anyone tried a WiModem232 with one of these and the terminal program? I'm not sure yet where to start on any kind of adapter cable, but the "as-is" PC-8001 might be able to support it? Or does the built in TERM really need something from the Expansion Unit?



To me the PC-8001 is somewhat like a hybrid between a 1980 PET 4032 and a C64 (in terms of being able to do color), almost like a SuperPET. It's not quite there in the same class as the IBM 5150. I recall early versions of the 5150, to add a hard drive you effectively had to add yet another chassis like the 5150 itself. IIRC, that's how early disk drives for the PET were like also - you were effectively buying another computer without a screen or keyboard.

I came across an article suggesting the FTC (federal track commission) sued NEC around 1988 essentially on false advertising (by claiming the PC-8001 could be upgraded to 160KB??) I can't find the article now, so maybe I have some details wrong. Anyone call anything like that?

But in terms of larger memory - when did CP/M start readily supporting more than 64K systems? (very early on, from the get go??) In other words, we can fault QDOS/MS-DOS for a lot of things, but it did do a good job of making 10x 64KB segments appear as one contiguous/conventional RAM. A lot of people have been "mystified" on how/why the IBM 5150 was so successful - surely part of it is the combination of factors: a single I/O + disk drive chassis, and an OS that "broke the 64KB barrier" in a Micro. (I never used CP/M that much often - I've read it essentially evolved in the DR-DOS lineage, and there was a "Concurrent CP/M" early on in the 1980s that never quite caught on; but when you look at something like the OSBORNE-I, it's still a 64KB-limited CP/M system.

 

[vwestlife]

I came across an article suggesting the FTC (federal track commission) sued NEC around 1988 essentially on false advertising (by claiming the PC-8001 could be upgraded to 160KB??) I can't find the article now, so maybe I have some details wrong. Anyone call anything like that?

In 1988, NEC got slapped by the Federal Trade Commission for "unfair and deceptive practices" because they advertised the PC-8001A computer as having 32K of RAM expandable to 160K, while only a programmer who wrote their own code could access the RAM above 64K, and there were no operating systems available in the U.S. which could: https://books.google.com/books?id=xFHtAAAAMAAJ&pg=PA501#v=onepage&q&f=false

NEC was ordered to contact everyone who bought an Expansion Unit and at least one extra RAM board for it, and then send everyone who responded a refund check. But they expected the turnout to be low, because the maximum refund of $150 per person would apply if less than 100 people responded.

My dad was still using his PC-8001A in 1988, but the refund offer didn't apply to him, because his computer came with the aftermarket "The Wedge" add-on, rather than NEC's own Expansion Unit.