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Posted By

MIRKOSOFT
on 2016-06-07
15:52:15
 How are looking Plussy users on Commodore 128's VDC video device?

Hi!

I want to ask as many as possible users of 264 Series computers users how they're looking on Commodore 128's VDC 8563 or 8568 and its improvements, both with 64K video RAM.
It's for now investigation... I need to know opinion of 264 users if they could have VDC available as 2nd video circuit, so how and what means?
Thanks for each opinion sharing.
Miro

Posted By

MMS
on 2016-06-07
18:37:57
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Hi,

I always found the VDC as a fantastic device and great achivement of big resolution on 8 bit machines. I felt sad, how complicated to reach and program that 16k (or 64k). I think this (and the slow down of C128 by VIC-II) were the main reasons, why C128 could not be evena bigger success (though 2 million sold units is not bad at all).
The VDC resolution 640x400 was such a nice resolution for a productivity SW, like GEOS, that with the proper size of RAM, it is almost the same like EGA for PCs. The 1571 was also pretty fast with burst mode. I dunno what was the CPU speed with VDC "no badlines" but could be pretty impressive.
I want one, if the access would be standardized with some standard drivers, easy to understand extensions, that could live paralel to the existing ones. ( Would be great to use the 64K foir 320x200x 121 free color like VGA chunky happy )

Posted By

MIRKOSOFT
on 2016-06-07
19:55:36
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Thank you for opinion.
Programming VDC is easy and access not interferes computer RAM.
Slow down C128 is for one chip only - VIC-IIe - cannot handle 2MHz and Z80's 4MHz.
64K video RAM offers theoretically data for 1024x512 pixels resolution.
Tested was 1024x296 pixel text mode, maximal reached is 800x600...
8568 features also EGA mode. When I'm writing about VDC maximum of colours is 16, interlaced modes looks like 136 color modes, but reality is 16, also in EGA mode.
Color mode edge is 640H, 8x1 color cells mode (16 colors in 8x8 pattern) edge is 480H, always is possible to use in color modes 8x2 color cells (8 colors in pattern).
320x200 in 121 colors is not possible, but 320x400 simulates 136 colors.
Features also double-width mode - aspect ratio like 640x200, but can use 8x1 cells.
I'm writing features of real use, of course 64K video RAM. Default 16K video RAM of C128/D allows 640x200 monochrome mode only, or color modes less resolution vertically.
With 128DCR came new 8568 chip with default 64K video RAM, but offers not composite greyscale output, this feature replaces EGA mode...
So, your opinion is 1st vote for VDC happy

Posted By

gerliczer
on 2016-06-08
06:32:27
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Bleh.

Posted By

siz
on 2016-06-08
07:05:54
 Re: How are looking Plussy users on Commodore 128's VDC video device?

I agree with gerliczer. Although probably it's not too complicated to create a VDC expansion board for the plus/4 as the VDC uses only two memory addresses to access it's registers and display memory I don't think it would make much sense nowadays. Yeah, the challenge is there but what would you use that for? None of the existing programs are able to use it. Perhaps with a custom KERNAL the programs without direct screen memory access would work but all of them are created with a 40 columns wide display in mind.
In my opinion it does not worth the effort. In spite of this maybe I would purchase one for a reasonable price out of curiosity but I have no high hopes about it.

Posted By

MIRKOSOFT
on 2016-06-08
09:57:26
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Magic of VDC is two IO addresses access - don't interfere computer RAM.
VideoRAM can be used also (no my choice) as RAMdisk...
For setting text mode, cursor, other needed things requires not extra Kernal, in all cases for Plussy it's independent desktop, without Kernal requirements. In case of C128 in Kernal are 2 read/write routines only and ESC+X desktop switch.
Ok, now VDC has score 1:2, I mean not more positive feedback.
Result will be next opinion.
I respect your opinion and thank you.
Miro

Posted By

MMS
on 2016-06-08
15:13:12
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Hi Mirko,
as you told, I am in! but it would be great to have a solution integrated into the device how to connect the VDC to modern LCD monitor or TV. Most of people has no Commmodore monitor any more.The RGBi output anything but compatible, due to the 15kHz rate and the strange pin output (not to mention the black/white composite output). Yeah, it is CGA compatible, but who has CGA monitor?
Yes, there are hacks to solve it, but some of them has strange colors, or costs too much.
Just connecting the C128 RGBi connector to an LCD monitor costs a 100€ board, so any itegrated solution (to have more modern output, eg scandoubler, DVI-I) would be more than welcomed.

Posted By

MIRKOSOFT
on 2016-06-08
19:44:15
 Re: How are looking Plussy users on Commodore 128's VDC video device?

For now, if will be device available for Plussy, it needs to get more positive votes.
Currently are in discussion extension details.
In case of output - we can add RGBI to S-Video converter (with A. Bairstow agreement) which allows connect VDC to TV or modern LCD, but it scales down resolution higher than 720H (768 is total maximum) and 576V (PAL) / 480V (NTSC) - picture is ok, but true higher resolution is scaled down, when we look at Commodore CRTs they offer similar limit, so it's not so big disadvantage.
I tested succesfully on C1084 resolution 800x600, tested (not me personally) was 1024x296 with warning of overheat or monitor damage. The same I tested with RGBI2SV (downscaled) and my CGA2VGA upscaler with turned off 1084 - no problem, in case of MOS 8568 EGA mode - this damages normal CGA / Commodore monitor 100%, so our choice is MOS 8563 (with one more output - composite greyscale)
Miro

Posted By

MMS
on 2016-06-09
00:16:31
 Re: How are looking Plussy users on Commodore 128's VDC video device?

well, i see the the others point, but it is worth to mention, that some VDCmodes allow 8x2 color in one attribute, means that any of the 8 (or 16) color can be used freely in one character area. as a gfx guy I see this as a fantastic video mode (though the fantastic plus4palette is ot available). You Can easily convert/crop any EGA picture downloaded from the net, and it is crazy how easy to make COLORFUL software sprites in such a video mode. . c64/c128 users were not impressed as they had athe VIC HW sprite, but plus4 can manage 2 color software sprite at it's best. not to Mention that vdc can work as a second monitor output, as far as I see. 720x 480 is a stellar resolution, though I am more interested in tge colorful gfx modes (i think it is 640x200 or 640x 400)

Posted By

MIRKOSOFT
on 2016-06-09
05:39:18
 Re: How are looking Plussy users on Commodore 128's VDC video device?

So - to color cells - it removes attribute clash not.
8x1 color cell means 2 user selected colors for 8 pixel horizontally, 1 pixel vertically (1 foreground, 1 background color), so in 8x8 block it allows use 16 colors and the same for 8x2 or 8x3 or 8x4...(higher Y makes less colors), default is standard, VIC HiRes like, 8x8 color cells.
When you're talking about fantastic (really is) Plussy palette - 121 colors in 320x200 in 8x8 cells - doing similar is possible with double-width mode (changes aspect ratio to 2:1) in resolution 320x400 interlaced in 8x1 color cells - interleaved frames making 136 color effect, but really are there simple 16 colors...and each 8x8 block can use 16 colors instead VIC HiRes 2 colors.
8x1 cells is tricky mode, but always is available 8x2 cells mode.
Resolutions on VDC are really user defined, only timing limited.
Common are: 640x480x16, 640x576x16, 720x700x2, 800x600x2, 640x512x16, 320x200x16, 320x256x16, horizontal limit reached 1024, vertical currently 700 pixels, real maximum reached not released Commodore 900 - 1024x800, but it used 128K videoRAM (unknown is RAM handling - if it could be known, we could do it), videoRAM of normal VDC allows theoretically space for 1024x512 pixels. Each interlaced mode no matter of color cells (as less as better) makes 136 colors (really 256 colors, but some are the same, so 136).
Miro

Posted By

Litwr
on 2016-06-09
12:45:41
 Re: How are looking Plussy users on Commodore 128's VDC video device?

VDC was almost completely abandoned by the software. No games, no GEOS, no demos, ... VDC is capable to do the same things or even the better ones that Amstrad CPC VDU does. However Amstrad has SymbOS, demos like https://www.youtube.com/watch?v=YJosZfm560Q etc... It is odd because Amstrad sold less CPC units than C128.
IMHO Commodore after Jack Tramiel gave up their fine 8-bit lines.
It will be curious to see VDC demo at Plus4. I coudn't find any good demo for VDC at youtube...
The interlace modes are useful only to see pictures I tried it with Amiga 500 - it was impossible to work - nobody used it for work or games.

Posted By

MIRKOSOFT
on 2016-06-09
12:53:39
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Ok, definitely 1:3.
Thank you all for opinions, it was needed for decision.
Plussy model is out of game.
Btw. Look at Risen from oblivion demo - VDC part
Miro

Posted By

MMS
on 2016-06-09
15:53:06
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Litwr, at a certain level you are correct. On the other hand there was a Geos128 that used high resolution mode, and looked much sharper than the VIC version:
Google image search results for GEOS 128

Posted By

Litwr
on 2016-06-10
00:34:19
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Miro, thanks for the link to Risen from oblivion demo. However this is a unique piece of software. BTW I repeat "It will be curious to see VDC demo at Plus4". happy
MMS, I spent 5-10 minutes with the net searching and I couldn't find any evidence that GEOS 128 uses VDC. I couln't even find GEOS 128 for download.

Posted By

MMS
on 2016-06-10
00:47:53
 Re: How are looking Plussy users on Commodore 128's VDC video device?

as Far as I know here is even a ROM chip version of GEOS2.0 you can plug into a free slot.

Posted By

RobertB
on 2016-06-10
02:21:13
 Re: How are looking Plussy users on Commodore 128's VDC video device?

MMS wrote:

> ...why C128 could not be evena bigger success (though 2 million sold units is not bad at all).

According to CBM engineers Bil Herd and Dave Haynie, 4 to 5 million C128's were sold.

Truly,
Robert Bernardo
Fresno Commodore User Group
http://www.dickestel.com/fcug.htm
July 30-31 Commodore Vegas Expo v12 -
http://www.portcommodore.com/commvex

Posted By

MMS
on 2016-06-10
04:31:40
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Hi, I also checked Wiki since then, and you are right. From such a high specified 8bit machine (when the PCs and 16 bit machines were available) this volume is fantastic result.

Posted By

RobertB
on 2016-06-11
01:39:52
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Litwr wrote:

> ...I couldn't find any evidence that GEOS 128 uses VDC.

Because GEOS 128 is an 80-column application, it has to use the VDC (From the Wikipedia article on the MOS Technology 8563 -- "The 8563 Video Display Controller (VDC) was an integrated circuit produced by MOS Technology. It was used in the Commodore 128 computer to generate an 80-column (640×200 pixel) RGB video display...")

> I couln't even find GEOS 128 for download.

http://pokefinder.org/index.php?s=geos+128&m=0&h=100

Truly,
Robert Bernardo
Fresno Commodore User Group
http://www.dickestel.com/fcug.htm
July 30-31 Commodore Vegas Expo v12 -
http://www.portcommodore.com/commvex

Posted By

Litwr
on 2016-06-11
05:35:05
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Thanks for this excellent link. happy I could find geos128.ZIP archive and the manuals. This GEOS 128 starts in the VIC mode. So composite monitor is required... However it is possible to switch to VDC RGB monitor. I have doubts though that some GEOS128 programs may work in the VDC mode. IMHO VIC mode is abundant...
IMHO C128 was the biggest deceit of the customers in the home PC history. They wanted upgraded C64 but got the same C64 plus two poor supported and artificially worsen semi-computers. GEOS128 looks much less popular than GEOS64.... I don't know the reason. Maybe it is the poor support too, isn't it?
BTW C+4 with VDC may work at full CPU speed or even in "the super turbo" (ntsc, 2.2 mhz) mode.

Posted By

MMS
on 2016-06-11
07:37:04
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Yeah, it would be a beast with no badlines...

Posted By

badco
on 2016-06-11
13:21:50
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Actually the slow down to 1 MHz is not just for the VIC. I/O df00/de00also needs to be at 1mhz for various things like the ram expander etc.

Posted By

MMS
on 2016-06-12
07:15:55
 Re: How are looking Plussy users on Commodore 128's VDC video device?

Yeah, I am sorry for the outcome, but you can count on me any time if you finally decide to realize it.
Do not take it wrong, the hardware developments (except the most welcomed SID Card) was never the strong part of the Plussy community. Even the Music Keyboard (can be easily attached to C16 without any HW modification) generated no intention to implement it on this machine.
Unfortunately most of the modifications worked out in the last 30 years required internal modifications, so it seems the remaining scene became sceptical on anything looks like an external working module. happy



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