• Please review our updated Terms and Rules here

A Long Look at the Panasonic Personal Computer JR-200U (1983)

Bill_Loguidice

Veteran Member
Joined
Mar 13, 2006
Messages
621
Location
Central New Jersey, USA
I rarely cross-post about my Armchair Arcade blogs here, but I think this latest one merits it since it's on a very obscure system that few have any familiarity with, the Panasonic Personal Computer (JR-200U), from 1983. I didn't do it as a formal article, obviously, so it's a very casual account of first exposure with lots of exclusive images. Enjoy: http://armchairarcade.com/neo/node/1598
 

carlsson

Veteran Member
Joined
Jul 30, 2003
Messages
6,275
Location
Västerås, Sweden
Wow! That loader screen on the Solitaire game looks mighty impressive, given the graphic limitations. If it had played music while loading as well, it had been truly groundbreaking for its time.
 

Bill_Loguidice

Veteran Member
Joined
Mar 13, 2006
Messages
621
Location
Central New Jersey, USA
That's just it, though, JUST the pre-loader screens were impressive, obviously using some type of machine language routines. Whether it was the fancy screen for Solitaire or the animated Panasonic logo and color flash, all that far overshadowed the poor relative quality of the actual program (and actual loader). It's easy to see how outclassed it was in 1983.
 

carlsson

Veteran Member
Joined
Jul 30, 2003
Messages
6,275
Location
Västerås, Sweden
Yep, but still it shows what is possible with a good amount of machine code. It is similar to what demo groups later have achieved on other platforms; often you can create much more awesome presentations if you don't have to bother with user input and arbitrary "scenarios". The JR-200 in some ways reminds me both about the vTech Laser-110/220 (?) and the COMX-35 (of which I recently acquired one).

A few other true oddballs to look for would be the BIT Corporation BIT-60 (Atari 2600 compatible?) and BIT-90 (ColecoVision/Sega SC-3000 compatible?). In particular the first one, there were very few el-cheapo home computers powered by a 6502. With Atari already in the computer business, it probably was to avoid competing with themselves they never made a real computer out of the VCS, even if there are 3rd party keyboards, tape storage systems et.al.
 

Bill_Loguidice

Veteran Member
Joined
Mar 13, 2006
Messages
621
Location
Central New Jersey, USA
Yep, but still it shows what is possible with a good amount of machine code. It is similar to what demo groups later have achieved on other platforms; often you can create much more awesome presentations if you don't have to bother with user input and arbitrary "scenarios". The JR-200 in some ways reminds me both about the vTech Laser-110/220 (?) and the COMX-35 (of which I recently acquired one).

A few other true oddballs to look for would be the BIT Corporation BIT-60 (Atari 2600 compatible?) and BIT-90 (ColecoVision/Sega SC-3000 compatible?). In particular the first one, there were very few el-cheapo home computers powered by a 6502. With Atari already in the computer business, it probably was to avoid competing with themselves they never made a real computer out of the VCS, even if there are 3rd party keyboards, tape storage systems et.al.

Those BIT Corporation machines are definitely interesting - the height of grey market engineering. I do have the Spectravideo computer add-on for the Atari 2600, which is the only "real" computer add-on for the system that I know of (with the ability to save and load programs on cassette). I also have the Sega SC-3000 (the one with the chiclet keyboard rather than the full stroke model (H)). I'm not big on import systems, other than ones from Japan, since power/display conversion issues are trivial with them, though I do have several European systems and the necessary converters. It gets tough for me when there's not an English-language component to the hardware or easily acquirable software, because the utility/usefulness drops dramatically for me, making it a dust collector.
 

carlsson

Veteran Member
Joined
Jul 30, 2003
Messages
6,275
Location
Västerås, Sweden
Amen to that! An undocumented computer soon loses its glory, unless it is in very good physical condition, perhaps mint in box. Of course I'm willing to reconsider that standpoint if I would come across something really exciting. Personally I prefer 220-240V and PAL, but that is due to my location.
 

tezza

Veteran Member
Joined
Oct 1, 2007
Messages
4,720
Location
New Zealand
Interesting article. I love reading about lesser-known models.

As an aside, I note that the only country outside Japan the prototype (JR-100) was released in was New Zealand.

This was common with "first-off-the-shelf" electronic goods from Japan during the '80s and '90s (and maybe still is?). New Zealand was (is?) regarded as a test market, where Japanese manufacturers would release new models and see if they would fly.

Being a relatively affulent modern western country, if they succeeded here in NZ, then they would most likely succeed in bigger markets like North America and Europe. On the other hand, if they bombed, a suppy and marketing effort to only 4 million people is not too big an investment to write off and (being an isolated country) not many outside NZ would know about it. The latter means the manufacturer's name (at least globally) would not be associated with a "failure" as such.

In this age of Globalisation this may no longer apply, but it was a cunning strategy back in the day.
 

tezza

Veteran Member
Joined
Oct 1, 2007
Messages
4,720
Location
New Zealand
Amen to that! An undocumented computer soon loses its glory, unless it is in very good physical condition, perhaps mint in box. Of course I'm willing to reconsider that standpoint if I would come across something really exciting. Personally I prefer 220-240V and PAL, but that is due to my location.

I agree. That's why I'd just love to get some docs on my EACA Colour Genie (anyone?).
 

CP/M User

Veteran Member
Joined
May 2, 2003
Messages
2,984
Location
Back of Burke (Guday!), Australia
I'm only familiar with the JR-200 which is mentioned along with a list of other computers - The Personal Computer Handbook by Peter Rodwell (1983/4). It looks like a nice machine, though the Keyboard is Rubber and comes with Audible Signals, which I hate in a computer - though it could probably be turned off and perhaps for somebody who's blind the use of Audible Signals in a computer would attract that Client ell.

256x192 high resolution graphics in 8 colours mightn't sound like much these days, for 1983 though that's pretty good.

What's with this loading screen business (I can't really see that), is it something like a Speedlock loading system found on an Amstrad? Since I managed to get into some loading systems which were deliberately made to look like Speedlock loading systems (but weren't), I can say that there was some serious poking around between the Hardware and even a True Speedlock loading system does this as well. I cracked one game which used the Speedlock because it was an eary Speedlock loading system - it was still a pain though compared with games which tried to make themselves look like Speedlock but weren't. The main secret was in the size of the loading program, most true Speedlock loading systems were over 2048b (the size of 1 Block in a standard loading file which included header and information).
 
Last edited:

carlsson

Veteran Member
Joined
Jul 30, 2003
Messages
6,275
Location
Västerås, Sweden
256x192 used to be a very good resolution, but often the screen is not truly bitmapped. Instead it is made up of characters from ROM or RAM. I believe most 8-bit computers has a limitation at 256 characters in a set, sometimes less than that. In that case, each character code can only be displayed once on screen, in a matrix like this:

@ABCDEFGHIJKL
MNOPQRSTUVW
XYZ[£]^ etc

You would define a custom character set of 256 definitions, in which you address individual dots based on where on the screen each character is located as above. If each character occupies 8x8 pixels, you can get a bitmapped area at most 16x16 characters = 128x128 pixels, which is much less than 256x192.

Some computers (e.g. the VIC-20) have special character modes where each character uses 8x16 pixels. In that case you could in theory get 32x8 double height characters = 256x128 pixels. In particularly the case of the VIC, it can not display that screen width but can nicely display e.g. 25x10 double height = 200x160 pixels.

I don't know how flexible the Panasonic computer is, but I believe it works with custom character sets as described above. A lot of the area is blank or filled with one colour, so one and the same character definition could be used many times, and only use unique characters for the detailed graphics.

I suppose the initial reason behind making loading screens is to give the user something to look at while loading, and to let him or her know progress is under way. Often the system loading routine is very bland. When you mention 2048 Kb, is that kilobit? 2048 kilobit equals 256 kilobyte, which is a lot even for CPC6128. Perhaps you mean 2048 bytes = 2 kilobyte?

I am of the old-school who uses SI units: k, M, G instead of Ki, Mi, Gi and also differentiates between lower-case b as in bit from upper-case B as in byte. A lot of people unfortunately don't adhere to this nomenclature, which makes it a bit fun everytime one speaks about millibit (mb). The same people tend to write kilo with capital K as in KHz or even Khz, when it really should be kHz.
 

CP/M User

Veteran Member
Joined
May 2, 2003
Messages
2,984
Location
Back of Burke (Guday!), Australia
Bugger I've hit the wrong button and my message was deleted before I could post it - can't be bother replying now! :-((

You are correct though 2048 bytes it should be not 2048 Kb, that would make it 2Mb wouldn't it?!

I'm familar with those odd VIC-20 symbols through the many type-ins I've seen for a VIC-20. The Amstrad's could also have simular control codes in BASIC type-ins, though they work in TP 'writeln' statements (though nobody could be bother writing programs with them since unlike a VIC-20 the character wasn't represented on the keyboard).

CP/M User.
 

carlsson

Veteran Member
Joined
Jul 30, 2003
Messages
6,275
Location
Västerås, Sweden
Ok. You say b, I say B, we both mean byte. By the way, the Amstrad does seem to have pure bitmapped graphics (like the ZX Spectrum, Commodore 64 and many more) so one would technically not have to resort to the simulative (?) method I described. Custom characters still are fine for displaying individual graphics, just like sprites.

Quite a few computers had character graphics, some more symbols than others. I recently had a look at my Atari 800XL and 130XE. They have the basic symbols except for one: two quarters of a characters filled:

Code:
***---
***---
---***
---***

At least I could not find it on the keyboard. The other symbols for one, two, three or four quarters of a character are there, using inverted graphics.
 

Bill_Loguidice

Veteran Member
Joined
Mar 13, 2006
Messages
621
Location
Central New Jersey, USA
RGB on the JR-200U

RGB on the JR-200U

We've been having a small discussion over at AA about the RGB output since I got it working with a handy Neo Geo AES composite cable. Top of our heads, it seems like this might be one of the first systems with an RGB output if we can date the system to its original 1982 Japanese origins. What do you guys think? It's certainly a contradiction for such a low end system to have such an unusual capability when it would be served just fine with a standard TV connection (unless it's just a by-product of the chipset used and of nominal cost to activate).
 

carlsson

Veteran Member
Joined
Jul 30, 2003
Messages
6,275
Location
Västerås, Sweden
Hm. The ZX Spectrum has RGB on its expansion bus, but I think it was released early in 1983. The same goes for the Oric-1 which has RGB. The Acorn BBC of course has RGB as well, and I think the first Model A was released in 1982. While I'm quite sure the Atari 400/800's don't have RGB on a connector (or at all), we must consider the TI-99/4 which as far as I understand has component video: Y Pb Pr, at least on the European version of /4A. It is similar to RGB but perhaps even more technically advanced, not until these days we have consumer electronics which output component video instead of RGB.

So yes, the Panasonic JR-200U might be one of the first, but not neccessarily the first home computer (if you consider e.g. an Acorn BBC Model A to be a home computer).
 

rmay635703

Experienced Member
Joined
May 29, 2003
Messages
491
Location
Wisconsin
I have a 1976 Casi Apollo VP2 that can output B/W composite in either combined or separated syncs in NTSC if that means anything, it was apart of a $25k computer photography setup though.

There was a circa 1980 CASI Rainbow color computer portrait machine based off a modded apple II that had RGB output and captured NTSC video frames. The images were pretty much brownish with little true color coming through but still looked OK for the time.

Both systems were bitmapped, I would really like to find a rainbow but sadly I have to go off others descriptions of it since I cannot locate one in the flesh as it was also apart of a $25k color computer portrait system.
 

carlsson

Veteran Member
Joined
Jul 30, 2003
Messages
6,275
Location
Västerås, Sweden
Hm yes, doesn't the original Apple II in itself output RGB in one way or another? Never mind, it is cool that a relatively low-cost computer like the JR-200U would have this feature. I wonder if the output is analog or TTL level.
 
Top