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Chuck(G)
December 15th, 2008, 11:52 AM
I've discovered that I've got what appears to be a new Plus/4 here (in original box). I was thinking of using it as a terminal, but note that the display is limited to 40 columns.

Is there a way to extend this to 80, or am I better off putting this thing back on the shelf?

carlsson
December 15th, 2008, 01:52 PM
Probably through software, a program that emulates 80 columns using 4x8 pixel characters. It has been done on the C64, and I believe the Plus/4 would be just as capable. However it won't look nice, may be rather sluggish and have limited colour resolution compared to the 40 column mode. When you say terminal, you mean to connect it via some serial port to another computer? In that case, you should probably try something else. How about a C128 or an cheap Amiga 500?

Vint
December 15th, 2008, 02:12 PM
I really like Plus/4's.
It runs a MOS 7501 CPU and a MOS TED chip which handled video, sound, and I/O. It's a 'lamed down' machine compared to many others, and kind of shot itself in it's own foot - so to speak - with non-standard joyports, missing many features that were becoming standards of the day, a keyboard many people didn't like at all (except me, of course). A practically worthless set of built in programs, etc., etc.
In my opinion it's nicest feature was it's version 3.5 of Commodore BASIC. It also had 60k of free space to play in.

Put it back on the shelf OR write yourself some nice programs in BASIC for it - that's the fun part :)
In the history of Commodore computers I believe it's an important 'spoke in the wheel' to any vintage collection.

carlsson
December 15th, 2008, 02:29 PM
I'm a part time Commodore collector but has never seriously considered including neither a Plus/4 nor a Commodore 16 into my collection. Maybe if it is dirt cheap.

The reason for being "lamed down" is said to initially had been to compete with the low-end inexpensive computers over here in Europe (read: Sinclair Spectrum), but as time went on engineers kept adding features to it, no longer making it the el-cheapo computer Jack Tramiel wanted it to be.

Actually, I have a non-functional Commodore 264-ish prototype motherboard dated August 1983, probably predating all complete 264, 364 or 232 prototypes you have seen on eBay. This motherboard is so old it still had DB9 joysticks and the card edge tape connector, both later changed to mini-DINs. From pictures, it has even been confirmed by former Commodore engineer Bil Herd. It is quite interesting how an early prototype would have C64 compatible connectors and not until a later stage in production they would switch to another kind. While the card edge connector surely takes a bit of valuable space, I'm not sure the joystick connectors save so much space by using mini-DINs instead of DB9s. Could it be Commodore's way to circumvent any patent infringes from Atari or that they'd make their own joysticks for this new machine, cashing in a bit more money?

Chuck(G)
December 15th, 2008, 03:22 PM
Sigh. Oh well, this was a freebie anyway. I was thinking that since the Plus/4 had a built-in UART and 64K ofmemory, it might make a good terminal in a pinch. Guess not.

As far as BASIC programming goes, I'd just as soon stick with C and assembly, or even JOVIAL, thank you.

carlsson
December 15th, 2008, 04:19 PM
Perhaps you could attach your own 6845 type board.. but then again, why would you bother using a Plus/4 in the first case if you need external hardware to make it useful? :)

I'm sure you will find some better device to use as a terminal. Most home computers from the 1980's will probably need some RS232 interface anyway, if only for converting voltages and pinouts. If you don't fancy using some old PC for this matter, I would still suggest a "gaming class" Amiga: having 80 column composite/monochrome, RGB or even RF output, plenty of memory and software, DB25 serial port pretty much according to standard IIRC, reasonably easy to transfer files to (compared with a lot else you could consider), full sized keyboard of decent quality...

billdeg
December 15th, 2008, 06:09 PM
If there were ample software in NTSC I'd use this system more. Yes you can swap the video mode to PAL, but the colors don't quite look right. There's a SYS command that swaps from PAL to NTSC.

The 7501/8501 chip goes bad, insist before you buy one that the owner test it for you.

There is a "rare" PLus/4. The Plus/4 was the official computer of the Canadian Winter Olympic Team 1984. These systems are identified by the Plus/4 logo on top which is different than standard and harder to find.

BD

Chuck(G)
December 15th, 2008, 07:06 PM
I'm sure you will find some better device to use as a terminal. Most home computers from the 1980's will probably need some RS232 interface anyway, if only for converting voltages and pinouts. If you don't fancy using some old PC for this matter, I would still suggest a "gaming class" Amiga: having 80 column composite/monochrome, RGB or even RF output, plenty of memory and software, DB25 serial port pretty much according to standard IIRC, reasonably easy to transfer files to (compared with a lot else you could consider), full sized keyboard of decent quality...

I still have the prototype terminal that I did for Fortune Systems a long time ago. It needs a serial keyboard, but I think I may be able to rig one up with an AVR and a PC keyboard.

Or just use a PeeCee like I'm doing now.

I did take the Plus/4 out of the box and hook it up to a TV. It seems to work okay. I've also got a 1541 and a printer for it, but game machines aren't my cup of tea.

Thanks anyway!

carlsson
December 16th, 2008, 06:10 AM
The Plus/4 was the official computer of the Canadian Winter Olympic Team 1984.
This fact is very bizarre, yet verified to be true. In the USA and other parts of the world, the Plus/4 was not released until the summer or even early fall of 1984. We all know the Winter Olympics are held in February or so, even those games which took place in Sarajevo, Yugoslavia 1984. It means the "commemorial Commodore" must have been launched in Canada at least a quarter, perhaps a half year before the official launch.

I'm willing to believe the Canadian Olympic Team edition was released at the end of 1984, to celebrate the success in the past games. Perhaps Canada didn't do so well in Los Angeles summer games, so it made more sense to celebrate the winter team. ;-)

docred
December 16th, 2008, 04:24 PM
Wow....I had absolutely no idea. I've always had a hard time finding +4 stuff up here regardless :)

Eh...we always do better at the Winter games than the Summer games I think, lol. We spend far too much of our year playing around in the snow :)

channelmaniac
December 19th, 2008, 07:21 AM
WOW.

If you have a WORKING Plus/4 consider yourself lucky. You should open it up and check to see if there's a heatsink on that TED chip. If there isn't, put a big one on it. Those things are well known for self destructing.

RJ

billdeg
December 19th, 2008, 07:37 AM
I would consider selling one of my extra working Plus/4's - U.S. power, boxed, and including the manual and a copy of a Plus/4 usergroup disk and whatever Plus/4 programs I can find that work (i.e. are NTSC if you're in the US, PAL if you're in England, etc). If anyone is interested make an offer via P.Message..

I am located in the USA.

Bill

docred
December 19th, 2008, 08:40 AM
I've actually got two of them - one was a planned purchase with box etc, the other was a lucky break out of the blue. I don't have much software for it. Thanks for the heatsink tip though, I'm going to check that on both of them.

Paulwa
December 19th, 2008, 06:13 PM
I got two +4's also from long ago. Blew one up trying to hook the wrong tape player up to it. The other one was like new I got at a yardsale for $40 in the box. Don't have the box anymore I guess, not sure but it worked just fine when I stored it away. I was always fascinated by this little machine but the built in programs were near worthless for me. I got several C64's and variants stored away with peripherals also. Got a couple of SX 64's, one working one not. Gonna have to go digging one day to see what I have. Haven't been around vintage computer forum for a long time. The market place looks interesting.
Paul