nippur72 Posted June 28, 2014 Share Posted June 28, 2014 what do you mean by "video RAM is memory mapped off of the CPU" ? I vaguely remember the Laser 500 graphic memory address space not being sequential, rows were arranged in a bizarre pattern I never full understood, I remember I had an hand-made table of pointers in my sprite routine for calculating the row where to start write. Quote Link to comment Share on other sites More sharing options...
JamesD Posted June 28, 2014 Share Posted June 28, 2014 what do you mean by "video RAM is memory mapped off of the CPU" ? I vaguely remember the Laser 500 graphic memory address space not being sequential, rows were arranged in a bizarre pattern I never full understood, I remember I had an hand-made table of pointers in my sprite routine for calculating the row where to start write. Computers like the ADAM use the TMS9918.VDC. The VDC has it's own RAM which is not directly accessible by the CPU and the CPU has to send commands to the VDC to access video RAM which makes access slow. The separate RAM does have some advantages but it means doing a lot of reading and writing to video RAM like the software font routines is going to be really slow. You could eliminated reads through the VDC by mirroring the contents of screen memory in CPU RAM but the 9918 doesn't use a conventional bitmap either so it would be a little complicated. Computers like the Spectrum, VZ200, etc... have the video RAM directly accessible by the CPU. You just read and write within the CPU address space to alter what is on the screen. Even if video RAM is paged like on the VZ hi-res mod, Drawing text on the hi-res VZ display is still very fast. I think the worst part of the VZ code was scrolling since you have to scroll across memory page boundaries. I used a buffer as an intermediate storage location. Thankfully, text does not get split between pages on the 64 x 24 character display so I only needed to set the memory page before printing to a line instead of for every byte of a character. The Apple II has a really bizarre screen memory layout and I wrote graphics text routines for it when I was in college. It's just a question of calculating the address before reading and writing to video RAM. I'm sure font routines could have been easily written for the Laser 500 but the small number of machines just didn't attract the right people. I'd be curious to seen more info on the Laser screen. Quote Link to comment Share on other sites More sharing options...
nippur72 Posted June 28, 2014 Share Posted June 28, 2014 Ok, thanks for the explanation. Yes, the L500/700 graphic memory was mapped in the CPU address space (I vaguely remember the ML routine being placed just before the video somewhere near &HBE00, and video probably starting at &HC000). The mode we used most was 160x96x16, because it was so colourful and totally unaffected by colour clash. It was nice to be free to paint anything with the paint program! And the result was a lot better than Commodore 64! Regarding the VZ200, I remember it very well (210,110 and 310), my only regret is that we didn't gave it the respect it deserved at the time--in our eyes it was the "poor" machine because of the limited video chip. BTW, I've just read in the Wikipedia page that the 6847 was also used in other home computers, that's completely new to me as I've always thought that it was just an odd chip from VTech. I thought it was odd because while in text mode, the fonts were strangely sharper than other home computers with similar resolutions. Later I discovered it was due to an hardware padding space put in the character matrix, giving the illusion of an higher DPI. I did not understand that at the time, and I also was puzzled why text in graphic mode was instead so "blocky". I remember several afternoons spent searching in RAM for bitmapped fonts and founding none (I expected it to work as for commodores). Then I deduced there was some kind of "magic" behind! Quote Link to comment Share on other sites More sharing options...
JamesD Posted June 28, 2014 Share Posted June 28, 2014 Ok, thanks for the explanation. Yes, the L500/700 graphic memory was mapped in the CPU address space (I vaguely remember the ML routine being placed just before the video somewhere near &HBE00, and video probably starting at &HC000). The mode we used most was 160x96x16, because it was so colourful and totally unaffected by colour clash. It was nice to be free to paint anything with the paint program! And the result was a lot better than Commodore 64!Do you know if the computer used bitplanes? This would allow an 8 color mode and may require writing to multiple addresses to set a single pixel. You would have to write to 3 addresses for an 8 color mode and 4 for a 16 color mode. Bitplanes were common on 16 bit computers but not on 8 bits. I think one Russian 8 bit used them. Regarding the VZ200, I remember it very well (210,110 and 310), my only regret is that we didn't gave it the respect it deserved at the time--in our eyes it was the "poor" machine because of the limited video chip. BTW, I've just read in the Wikipedia page that the 6847 was also used in other home computers, that's completely new to me as I've always thought that it was just an odd chip from VTech. I thought it was odd because while in text mode, the fonts were strangely sharper than other home computers with similar resolutions. Later I discovered it was due to an hardware padding space put in the character matrix, giving the illusion of an higher DPI. I did not understand that at the time, and I also was puzzled why text in graphic mode was instead so "blocky". I remember several afternoons spent searching in RAM for bitmapped fonts and founding none (I expected it to work as for commodores). Then I deduced there was some kind of "magic" behind!Green screens were popular on B&W machines with black on green characters supposedly the most readable. That's why they used that color scheme for the font in the 6847. Your eye blends the black together because it's black between the pixels so it looks higher res where you see individual pixels on lighter colored fonts. Funny thing though, some people complained because the Tandy CoCo text mode was black on green. Later models of the 6847 added true lower case characters in ROM. The chip was set up to it could use external ROM for fonts. The NEC Treck used this for upper and lower case and the Japanese version could display Katakana characters if I remember right. Text in VZ graphics mode was so blocky because the VZ didn't support the higher resolution graphics modes. Funny how things look like magic to a kid. 2 Quote Link to comment Share on other sites More sharing options...
nippur72 Posted June 28, 2014 Share Posted June 28, 2014 No it didn't use bit-planes I'm quite sure, if I remember correctly the 16-color mode was just writing a semi-byte in the upper or lower part of the byte (pixel). As for the "increased sharpness effect" in the 6847 I was referring to the hardware pixel spacing between characters, they made an 8x8 matrix looks like a 12x12 (or something like that--I don't really know how many hardware pixels they added, I should check it in the emulator). Quote Link to comment Share on other sites More sharing options...
enthusi Posted July 1, 2014 Share Posted July 1, 2014 My Laser500 is in a very nice condition (though without any manuals/tapes/etc). I expect a second child and to be honest, the Laser500 is not on top of my 8-bit-Hardware list, so I wont spend much/any time with it probably. If anyone would want to buy it? Quote Link to comment Share on other sites More sharing options...
enthusi Posted November 24, 2014 Share Posted November 24, 2014 Hi, the laser500 is now for sale among some other things/games: http://www.ebay.de/sch/martinwendt/m.html?item=201224761028 Quote Link to comment Share on other sites More sharing options...
MADrigal Posted November 24, 2014 Share Posted November 24, 2014 sorry the link points to a list of items. the item n. 201224761028 apparently is a c64 game, "usagi yojimbo" Quote Link to comment Share on other sites More sharing options...
gilles Posted June 14, 2015 Share Posted June 14, 2015 I had the scart cable for the laser 500 but converted it slighly to fit a sharp mz700 (fr) I'll probably rebuild a cable today since I'm preparing the machine for an exchange. I think I'll be able to send pinout anyway pinout is always the same for such machines: _ find ground and 12v _ find composite sync (or mono image) _ find the 3 colors (need to know the mapping with color codes) this makes 6 pins. other pins can be sound (not sure here because the laser 500 has a small loudspeaker) or separate H and V sync. Quote Link to comment Share on other sites More sharing options...
carlsson Posted July 29, 2015 Share Posted July 29, 2015 Every now and then I look, but still I haven't found any software resources for the 350, 500 or 700. I understand it has some support in MESS so at least the ROMs must've been dumped, but probably it is one of few computer lines that is emulated but with next to no available software. Perhaps it is time to port some BASIC games from other systems, just to have something to load... Quote Link to comment Share on other sites More sharing options...
nippur72 Posted July 29, 2015 Share Posted July 29, 2015 yeah that's very sad, we had plenty of software for these machines (both homemade and commercial) but all was lost. Also, I don't think everything was dumped, for example the ROM that came with the disk-drive expansion I think is lost forever (it extended the basic with commands like DLOAD and DIRECTORY). Quote Link to comment Share on other sites More sharing options...
carlsson Posted July 29, 2015 Share Posted July 29, 2015 (edited) There is someone on Flickr who posted a screenshot of Moon Patrol a couple of years ago, supposedly loaded from floppy disk so at least one of those should still exist. The poster was pointed to this thread and asked if they could dump it somehow. I read on Spanish Wikipedia that it originally was sold with some tapes of games, but no trace of those. User CatPix in this thread posted last year he's got the demo tape from INFP Scheidegger, which probably should be transferred to WAV any time soon. My machine also comes in a carrying bag from Scheidegger with a generic BASIC course that IIRC doesn't even list the set of commands available to the machine, but no demo tape. This page has seemingly some material, at least the manual in English: http://retroordenadoresorty.blogspot.com/p/cannon.html Edited July 29, 2015 by carlsson Quote Link to comment Share on other sites More sharing options...
Platis Posted November 16, 2015 Share Posted November 16, 2015 How about the sound capability of Laser 350/500/700 ? Quote Link to comment Share on other sites More sharing options...
nippur72 Posted November 17, 2015 Share Posted November 17, 2015 @carlsson as far as I remember all games were sold on tapes, and I vaguely remember it was hard to transfer them to disk, because of the a special loader used. @Platis all lasers had poor sound capabilities, there was a piezoelectric speaker driven by a 1-channel square wave generator. Sound could be produced from BASIC with SOUND and PLAY commands, I remember they were compatible with GW-BASIC, so you could type in a listing for e.g. IBM pc. Quote Link to comment Share on other sites More sharing options...
Platis Posted November 17, 2015 Share Posted November 17, 2015 (edited) So Laser 350/500/700 was not much better than the 200 in that respect? Can't understand why the they didn't throw in a real sound chip? Whatever homecomputers they thought they competed against, almost all had better sound capability around this time, strange!? Seems like many of this computers was sold in France/Italy/Germany/Holland, hard to understand why dokumentation and games are so rare today? How was the pricetag in Italy compared to spectrum/atari/C64/MSX? I also have a 500, but no manual! Haven´t played a lot with it get, but I like the better colour/graphics and the 80X24 mode compared with Laser 200! Edited November 17, 2015 by Platis Quote Link to comment Share on other sites More sharing options...
carlsson Posted November 17, 2015 Share Posted November 17, 2015 I believe "many" is a relative term here. Even if 50% of all machines made were sold within a single country, that would not need to equate to a large user base. According to one user input on Old-Computers, a Laser 500 with floppy drive cost correspondingly to 457 Euros in May 1985, obviously once converted from Franc. That could be compared to a Thomson MO5 which cost ~541 Euros in May 1984, one year earlier. I suppose there should be some old computer magazines with adverts for all those computers which would give a better picture of the price point. Quote Link to comment Share on other sites More sharing options...
nippur72 Posted November 18, 2015 Share Posted November 18, 2015 Yep it was a pity it didn't have a decent sound chip, but at least the video was good enough to keep us busy. Its major feature was the 160x200 color mode which was fully addressable (no color clashing). Perfect for games. Regarding to its limited diffusion among users, I see two different reason. The first is that L500/700 appeared too late, the world was already moving to 16 bits (Amigas etc). The second, is that all these machines weren't sold in regular stores (at least here in Italy), they were only sold along with the BASIC computer school course. And when they switched to selling 500s in place of the old 310, people just stopped buying computer courses, so that's why they are so rare machines. Quote Link to comment Share on other sites More sharing options...
Platis Posted November 18, 2015 Share Posted November 18, 2015 (edited) This "BASIC computer school courses" was it in English or Italian? Is it SECAM or PAL in Italy? Seems like VTECH moved to do a lot of own ASICs for its computers/toys-line at this time, especially for graphics(500, 128ex etc). I have two other cool computers/toys from VTECH, IQ and IT Unlimited! I find these somewhat interesting, they have a lot of applications software inbuilt , even BASIC(but sadly very restricted BASIC, no graphics/sound etc). http://www.danielsays.com/ss-gallery-vtech-iq-unlimited.html Edited November 18, 2015 by Platis Quote Link to comment Share on other sites More sharing options...
nippur72 Posted November 18, 2015 Share Posted November 18, 2015 in Italy we have PAL (luckily for us). BTW this reminds me of one thing I've never fully understood: Laser 500 had 1-pixel wide fonts and it was very well readable both on 40 and 80 columns mode. On the contrary the Commodore 64 had to use 2 pixels wide fonts to be readable on 40 columns. I wonder if that depends on poor video signal generation on the C64 side. Quote Link to comment Share on other sites More sharing options...
Platis Posted November 18, 2015 Share Posted November 18, 2015 What were the differences between 700 and 750? Quote Link to comment Share on other sites More sharing options...
StarshipUK Posted November 18, 2015 Share Posted November 18, 2015 What were the differences between 700 and 750? 50. 2 Quote Link to comment Share on other sites More sharing options...
nippur72 Posted November 19, 2015 Share Posted November 19, 2015 from http://www.old-computers.com/MUSEUM/computer.asp?st=1&c=449 "The memory size is also bigger compared to the old series and ranges from 16K RAM for the Laser 350, to 128K RAM for the Laser 750. The Laser 500 and 700 have 64K." Quote Link to comment Share on other sites More sharing options...
carlsson Posted November 19, 2015 Share Posted November 19, 2015 (edited) Yes, C64 video output is far from the most crisp. As I noted before, I found the 80 column mode on my Laser 500 to be sharper than the 40 column mode. Generally, I'd say most VTech machines were mail order, one way or another. Either bundled with a course or similar, or sold on its own but probably only occasionally in stores. This usually held true for most of the smaller brands, not enough demand to get them into the stores, not enough software to support buyers anyway. Some may have appeared in stores after a while when a market had formed, but to me VTech/Laser is a typical mail order brand. Perhaps things were different in other countries, in particular in the USA where I got the impression that at least the Laser 128 series did fairly well. Edited November 19, 2015 by carlsson Quote Link to comment Share on other sites More sharing options...
+Gemintronic Posted November 19, 2015 Share Posted November 19, 2015 Which units were battery powered? Quote Link to comment Share on other sites More sharing options...
The Usotsuki Posted November 19, 2015 Share Posted November 19, 2015 Well, the 128 already had a software library when it came out. That absolutely had to help it. Quote Link to comment Share on other sites More sharing options...
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