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few quick question on Commodore Colt

Yhep, did all that. The drive is 32-bit so it's all set as the primary partition and its active. But for whatever reason the system will not boot from it
 
Alright. think i'm about done with it.


got it booting from a 32mb industrial grade CF card and added a sound blaster 1.0. not sure what to fill the third isa slot with. maybe a mem expansion. probably will never get used but feel a little empty inside knowing there's a unused slot. I'm sticking with the 8088 and not going v20 because this machine will be strictly CGA so going for max compatibility speed wise.

right now since I don't have a cable to connect the monitor I'm using the composite video port. so far the games I've tried Leisure suit Larry and Prince of Persia are in black and white. is this because they do not support composite CGA? and game suggestions for testing the composite cga?
 
No luck with these cables http://www.ebay.com/itm/Commodore-1...861?pt=LH_DefaultDomain_0&hash=item43b234164d

they connect ok but they image is just a mess of rolling lines. it does this regardless if the monitor is set to digital or analog.

composite seems to work okay. there are 3 settings for the switch on the front of the monitor (comp, sept, rgb) comp gives me a fuzzy image, sep. gives me a better image, these work if I have a composite cable plugged in. if I select RGB I just get the crazy smashed rolling image. adjusting the knobs for v and h hold doesn't help if I switch the switch on the back of the monitor from analog to digital RGB the picture gets brighter but that's it.
 
composite seems to work okay. there are 3 settings for the switch on the front of the monitor (comp, sept, rgb) comp gives me a fuzzy image, sep. gives me a better image, these work if I have a composite cable plugged in. if I select RGB I just get the crazy smashed rolling image. adjusting the knobs for v and h hold doesn't help if I switch the switch on the back of the monitor from analog to digital RGB the picture gets brighter but that's it.

It could be possible that your 1084S is expecting to get composite sync in RGB mode, which an Amiga does provide, but a PC with CGA (or the C128's RGB output) does not, because it only provides separate H and V sync signals. Perhaps later variants of the 1084S, made after C128s and PCs with CGA were discontinued, dropped support for separate H/V sync signals, and only work with composite sync.

And note that in luma/chroma (separated) mode, you will get a clearer image, but you won't get any color, because you're only feeding it with composite video, not luma/chroma video. To get color you'll need to switch it into composite video (CVBS) mode, which will give you that lovely blurry, rainbow-fringed text. :)
 
I have a Commodore PC20-III (same as the Colt really) with a Commodore 1084S, and a proper RGB cable, which works fine, no need to connect composite either. I doubt that Commodore changed it at any point. The RGB input was mainly for C128.
It will not do colour composite by the way.
I also used a Philips CM8833 (same thing as a 1084S really), and same story there. Works perfectly with RGB cable, and composite works as well, but not in colour.
I know the Commodore outputs composite in colour (with PCjr-compatible artifacts it would seem, not the same as CGA at least), because I had it connected to an NTSC colour-compatible capture device and LCD TV.
 
I have a Commodore PC20-III (same as the Colt really) with a Commodore 1084S, and a proper RGB cable, which works fine, no need to connect composite either. I doubt that Commodore changed it at any point. The RGB input was mainly for C128.
It will not do colour composite by the way.
I also used a Philips CM8833 (same thing as a 1084S really), and same story there. Works perfectly with RGB cable, and composite works as well, but not in colour.
I know the Commodore outputs composite in colour (with PCjr-compatible artifacts it would seem, not the same as CGA at least), because I had it connected to an NTSC colour-compatible capture device and LCD TV.

Probably the reason you're not getting colo(u)r is because you're trying to display NTSC video on a monitor designed for PAL. :)

The opposite is true as well -- after adjusting the V-Hold, you can display PAL on an NTSC monitor, but it will only be in black & white, due to the difference in color subcarrier frequency between the two systems.
 
Probably the reason you're not getting colo(u)r is because you're trying to display NTSC video on a monitor designed for PAL. :)

Indeed, but in that era it was already uncommon to find monitors that could handle both 50 and 60 Hz signals.
There are however displays out there that can handle both, including colour.
The Commodore 1084S just isn't one of them.

Anyway, I was merely giving my experiences with the 1084S to confirm that it should work in colour with RGBI (note that this is the TTL RGB input, the Amiga uses the analog RGB input, which is a different connector on the monitor), but that it can not decode NTSC colour information. I was not looking for an explanation myself, I already know how and why.
 
So what I'm getting out of this is that the 1084s will do rgb from the colt with the right cable but not do color composite just b/w. It doesn't match but I guess I should go back to my Tandy CGA monitor till I find an appropriate monitor.
 
So what I'm getting out of this is that the 1084s will do rgb from the colt with the right cable but not do color composite just b/w.

That is correct. The 'TTL RGB' input on the 1084S is a CGA-compatible digital RGBI interface. I bought a cable for that back in the late 80s when I started using a Philips CM8833 (basically the 'real' thing the 1084S is a rebadge of) as a CGA colour monitor for my Commodore PC10-III.
My CM8833 has since died, but I still have the cable, and I use that with a Commodore 1084S which I got recently.
I used this 1084S on my Commodore PC20-III, my Philips P3105 with ATi Small Wonder, and my IBM 5160 with real IBM CGA card.
They all work fine.
 
You'll have to check the pinout on the monitor. I believe on the 1080 I've got, it's wired straight through for CGA.
 
I am amazed at all the different versions of 1084 monitors.

It was because of cost-cutting. After Phillips could no longer make them cheap enough, Commodore switched to Daewoo, using a cheaper CRT with a larger dot pitch.
 
It was because of cost-cutting. After Phillips could no longer make them cheap enough, Commodore switched to Daewoo, using a cheaper CRT with a larger dot pitch.

Yeah, but in the above picture this one looks like it might be a toshiba manufactured monitor. It looks like my 1080.
 
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