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Any info on Video Technology Laser 500 computer?


31336haxx0r

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A while ago, a VTech (Video Technology) Laser 500 home computer found its way into my collection.

 

vtech_laser500_1.jpg

 

Resources regarding that machine are scarce. The most useful information I found was this Spanish Wikipedia arcticle.

Does anyone happen to know more about that computer, like pinouts, wiring diagrams, software and programming information? Maybe even the scan of its manual? Is it a worthy collectable?

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In theory there is a section at the CreatiVemu forum, but I'm afraid there are no more resources to be found there. I don't know if there is a VZ series community where the Laser 350, 500, 700, 750 would be considered side-topic. Perhaps you can try VZ-ALiVE?

 

It seems Video Technology made several different series of computers which have very little in common and thus would be scattered among the Internet:

 

Laser 50 = Z80 handheld computer

Laser 100, 110 = Z80 TRS-80 clones

Laser 200, 210, 310 = Z80 TRS-80 clones with colour (not 6809 CoCo)

Laser 350, 500, 700, 750 = Z80 standalone computers, no longer TRS-80 clones?

Laser 2001, Creativision = 6502 computers similar to Z80 Colecovision

Laser 3000 = 6502 Apple ][+ alike

Laser 128, 128EX, 128EX2 = 6502 Apple ][ clone with legal ROM

Laser XT Compact & similar models = 8088 IBM XT clone

 

Some of those are known as VZ-nnn, some were rebranded by Salora etc. I might have overlooked some series, but in general it seems they made a few too many series to create a following.

 

Good luck with your hunt, and if you find a community, user group, mailing list aimed at various vintage Video Technology creations (not counting v-Smile etc) it might be useful to try and unite resources or at least exchange links. Often these computers are the kind you get a stray topic here and there at various general vintage computing forums.

Edited by carlsson
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Laser 50 = Z80 handheld computer

Laser 100, 110 = Z80 TRS-80 clones

Laser 200, 210, 310 = Z80 TRS-80 clones with colour (not 6809 CoCo)

Laser 350, 500, 700, 750 = Z80 standalone computers, no longer TRS-80 clones?

Laser 2001, Creativision = 6502 computers similar to Z80 Colecovision

Laser 3000 = 6502 Apple ][+ alike

Laser 128, 128EX, 128EX2 = 6502 Apple ][ clone with legal ROM

Laser XT Compact & similar models = 8088 IBM XT clone

 

 

This is by far the most comprehensive list of their computer models. The ones that are not toys. Thank you! The Laser 200/300 (aka Dick Smith) was big in Australia some 20 years ago. Sadly it is not compatible with the 500/700 series. I'm afraid the folks at VZ-ALiVE only know those, but it is worth a try. :)

Edited by 31336haxx0r
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Seob, as it turns out I am the owner of your former Laser 2001. :)

 

I've also heard about the Sanyo direction but don't know exactly which models it applied to. I also wonder if the peripherals are somewhat cross-compatible between the different lines. The expansion ports visually look similar but it doesn't mean the signals are the same.

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Seob, as it turns out I am the owner of your former Laser 2001. :)

 

I've also heard about the Sanyo direction but don't know exactly which models it applied to. I also wonder if the peripherals are somewhat cross-compatible between the different lines. The expansion ports visually look similar but it doesn't mean the signals are the same.

Nice to know. Did you get the games working? I didn't have a tape deck to check out the game and demo tape. What kind of programs where on the demo tape?

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Yes and no. I got two tapes: Sonic Invader for Laser 2001 which loads fine. A WAV recording can be found here (4 MB).

 

The other tape was Demonstration Tape for Laser 200 Color Computer. Notice the missing "1" - this one obviously was for the Laser 200/VZ series and thus won't load on a 2001 so I traded it further to a Laser 200 owner. Your images of the two tapes still remain on the Old-Computers.com site and despite I tried to contact them explaining the mix-up, nobody from that web site seems interested in correcting the false information?

 

As a side note, the Laser 2001 and the Creativision Basic use two completely different tape formats although being so closely related. The Laser 2001 Basic also is not compatible with the Creativision Basic, and if you try to run Creativision Basic on a Laser 2001, none of the keys respond to input anyway. It really seems like VTech did all they could to make each machine as incompatible with the others as possible...

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Prop... what? It sounds very un-Video Technology to develop or even include custom chips that were not at least a little off the shelf components. Maybe it is a clone of some other video chip, integrating a different solution?

Actually, they started making their own chips for the Laser 128 Apple clones and the VZ300 had a custom gate array to do address decoding, so a custom video chip does not surprise me. But I wouldn't be surprised if it's based on another chip.

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Interesting...

 

Stuff about ROMs

 

More stuff

 

So I now know that OS ROM and character set ROM are two seperate chips. Makes sense, as they probably had at least one character ROM for the Asian market(s) and another one (or more?) for the rest of the world. Dammit, I NEED to rig up stuff to read out ROMs!

 

Edit: I should start to compile all that stuff somewhere.

Edited by 31336haxx0r
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Hm, I know I have opened up my Laser 2001 and probably took pics, but I don't remember if I read the exact chip numbers from the board. I remember as much as the ROMs are soldered to the board, which is the sole reason why I haven't dumped them. I'm sure a talented repairman could desolder them without damage, read the chips and perhaps even install sockets to put them back into, but my skills with a soldering iron, sucker etc tells me I should stay away from hacking a very rare and valuable computer.

 

The pictures I uploaded to the CreatiVEmu site only include an interior picture with the RF shielding still in place, so one can't even see the chips on that picture. Since I tend to remember the ROMs were soldered to the board, it suggests I have removed the shielding at least once.

 

But anyway, I'm sure VTech made their own chips from blueprints of others. It was any possible R&D and improvements on existing designs that boggled me slightly.

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I too cannot believe they developed a whole freaking video chip from scratch. An address decoder chip, okay. But not a video chip. Let's have a look at the graphic modes:

 

The text modes

 

40 x 24 in 16 colors

80 x 24 in 2 colors between 16

 

The graphics modes

 

GR0 = 160 x 96 with 16 colors

GR1 = 160 x 192 with 2 colors between 16

GR2 = 320 x 192 with 2 colors between 16

GR3 = 160 x 192 with 16 colors

GR4 = 320 x 192 with 4 colors between 16

GR5 = 640 x 192 in 2 colors between 16

 

Take a look at the colors:

http://es.wikipedia.org/wiki/VTech_Laser_700#Video

 

 

The CGA card used in 808x PCs/XTs has a 6845. Now let's have a look at CGA text and graphic modes.

Text modes:

 

40×25 characters in up to 16 colors.

80×25 characters in up to 16 colors.

 

Graphic modes:

320×200 pixels, 4 colors.

640×200 pixels, 2 colors.

 

 

Again, take a look at the colours:

http://en.wikipedia.org/wiki/Color_Graphics_Adapter#With_an_RGBI_monitor

 

Almost the same 16 color palette!

 

Given that the Laser 100/110/VZ200/300 (which are TRS-80 Model 1 clones) used the 6847 like the TRS-80 Color Computer, I assume it's their derivative of a 6545/6845/6847.

 

The Z80 as well as the 8088/8086 are descendants of the 8080. All of those processors use a design that employs "ports" and apparently there is a CP/M80 disk for this computer. Hmm....

Edited by 31336haxx0r
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For that matter, we should not ignore the Amstrad/Schneider CPC series which have a bit similar graphics. Actually I was first going to suggest this series of Laser computers might have bits of common heritage with the CPC, although probably not clones of those.

 

The choice of a palette is not so strange if you consider digital RGB only has eight possible combinations plus an intensity bit for a total of 16. It should be added 6845 is a "video address generator" or CRT controller while a 6847 is a complete "video display generator". As far as I understand, a 6845 never generates a whole image by itself, it is just a helper component in a circuit while the 6847 would do more of the work itself. Is this correct?

 

When it comes to the Sanyo reference, I just found the box of the German edition 2001 which was imported by Sanyo Video Vertrieb GmbH & Co in Hamburg so perhaps they never rebranded VTech computers but just were the agent.

 

Here is a Wikipedia page trying to summarize known home computers by the type of video hardware:

http://en.wikipedia.org/wiki/List_of_home_computers_by_video_hardware

Edited by carlsson
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I don't know anything about the CPC and very little about the 6847. All I know is my old trusty CGA card has a 6845 with external character set ROM and HEAPS of 74xxx chips aboard, that probably create the video signal. Maybe the VTL video chip is some sort of crossbreed between 6845 and 6847? Also, it has 80 pins, while the 684x have 40. Pins cost money. That chip must be handling some more stuff then, I guess.

 

I saw a German ad for the Creativision. It was sold by Sanyo, too. So maybe they were just the international distributor for VTech computers.

 

Edit: I just dug out my trusty old CGA adapter. The sole socketed chip is a "AM9264DPC34147" (emphasis added). The VTech character ROM is a "TMS 2364". I'm positive those two chips are PROMS of the same size.

It was JamesD's suggestion of 684x chips that started making me think about that CGA stuff. :)

 

Edit2: Wait! The CGA's char ROM has 24 pins while the VTL char ROM has 28! :o

Edited by 31336haxx0r
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2364 is an 8K ROM chip in DIP-24 package.

2764 is an 8K EPROM chip in DIP-28 package.

27128 is a 16K EPROM chip in DIP-28 package.

 

It is quite possible your 27-0401-00-00 is an one-time-programmable (OTP) 2764 or similar EPROM, or at least directly pin compatible with one. This is a common problem with old computers and video games when you want to replace a broken ROM with EPROM, that you need an adapter.

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  • 3 months later...

nice machine the Laser 500, I know it quite well, having played with it for almost 3 years in my childhood during the '80s. It was the machine where I started to learn programming seriously because of the more advanced BASIC language, the 80 column display and the 16 colours unclashed graphic mode.

 

A friend of mine managed the major computer club for the VZ-machines here in italy; it was a sponsored club so we had access to all machines and peripherals. I remember we had a VZ-plotter, VZ-joysticks, and VZ-disk drive 5"1/4 with the CP/M system too.

 

We wrote several programs for the 500 (in basic) that were published on the club's magazine. It was a great fun. I remember of a word processor, and a painter program (called "magic paint") we used to draw screen intros. There were also (few) assembly written commercial games sold on tapes.

 

Unfortunately I no longer have the machine and the software was lost during some house cleaning. I wish I had kept at least the software to run it in the emulator, what a pity!

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