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Tandy CM-11

Pffft!

I LOOKED at rs.com, but neither the model nor catalog number turned anything up during searches. I *ASSUMED* "search all of RS" means search all - including support!!!


Thanks guys


Tony
 
It's a very nice monitor (assuming it is up to spec.) I used several in the late 80's.

I wanted one for my 1000SX, but my dad wanted to save $100 and we got a CM-5 with the monster dot pitch instead ;) .

As CGA monitors go, they are among the best I've used. It's a particularly good choice for a Tandy 1000, since it supports the Tandy adaptor's extra scan lines in text mode.

Dave
 
to my knowledge, there are no extra scan lines in text mode. At least not with the original T1Ks. I don't mean to be a troll, but I think all Tandy's CGA compatible monitors stank. My very first computer was a T1K, and I had to spend extra money to get the "better" monitor. Started fishing around, and started reading BYTE, and learned what I really could be getting for my money. Somehow decided on a 2000 though. Go figger.
 
Gotta agree, the very crappiest looking monitors I've ever seen were Tandy (the VM-1 VGA is blurrier than most peoples CGA displays). OTOH, some of the best looking displays I've ever seen were also Tandy (how can you find any fault with the CM-1 hung off from a T2K, one of the prettiest color displays ever?).

--T
 
I think yer talking about the vgm-1 Terry. The vm-1 was the mono unit for the 2000 and was exceptionally nice. And IMHO the CM-1, though acceptable, was a bit on the course side. Not unusual for it's time period though. Both were made by Mistubishi. NOW, the CGA version of the CM-1 which was sold for the Leading Edge Model M (the equivalent of the Sperry PC) was AWFUL. Perhaps the unit that I obtained was just awfully used (doubt it). Pixels the size of tennis balls. Guessing about .52mm dot pitch. Had the exact same casing as the CM-1 though.
 
I have a CM-11 on my Tandy 1000HX, seems like a decent CGA monitor to me. I originally had a CM-5 shipped with that 1000HX but the monitor broke in shipping so I never got to see how it looked (got all my money refunded and spent some on the CM-11).

What I want to know is why most CM-11's have the black frame around the screen and mine is all white (does say CM-11 on the back tag)?
 
I dunno, but I have a TRS-80 Model I monitor that has black paint instead of the usual wood-grain look. Not sure how rare that variant is, but it's the only one I've seen.

--T
 
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Here's the quote from the Tandy 1000 FAQ about the extra scanlines. With the Tandy 1000 (SX, TX, HX, EX, at least) version of MS-DOS, you could type "MODE 200" to switch to 200 scanlines from the default of 225.

You could also type MODE TV to switch to NSTC refresh and 40 columns if you wanted to plug the composite out into your TV!

Tandy was really annoying in that they usually had two version of every type of monitor: a "high-end" one with a normal dot pitch, and a "normal" one with a huge dot pitch that looked awful. They did this with the CM-5 and the VGM-1.

Of course, a good EGA compatible multiscan would probably give you the best image from the Tandy CGA. I do remember the CM-11 as having a good image on a very black non-glare tube.

*********

"One non-standard thing that Tandy did was to use 225 scanlines for text modes in CGA, giving somewhat clearer text. IBM standard is 200 scanlines."

http://www.oldskool.org/guides/tvdog/1kfaq.html
 
well I see that's seems to be the popular consensus. But where is that info coming from? It's not impossible that they couldn't have created a different screen mode by directly programming the 6845, but if that mode was to work with a CGA monitor (and the 1000's to my knowledge output nothing but CGA or CGA to composite), the overscan lines would have to be reduced (all screen modes regardless of what card is being used have some overscan). Has anyone successfully programmed in that mode? It's the first I've heard of it, is why I'm questioning it.
 
well I see that's seems to be the popular consensus. But where is that info coming from? It's not impossible that they couldn't have created a different screen mode by directly programming the 6845, but if that mode was to work with a CGA monitor (and the 1000's to my knowledge output nothing but CGA or CGA to composite), the overscan lines would have to be reduced (all screen modes regardless of what card is being used have some overscan). Has anyone successfully programmed in that mode? It's the first I've heard of it, is why I'm questioning it.

I've been trying to understand this 225 scan-line mode better, and I've been digging though the often infuriatingly vague Tandy 1000 tech manuals to try to figure it out.

As far as I can tell, this is what's going on:

All graphics modes run in normal 200 line mode with the option to color the overscan lines (like the PC Jr.) to make borders.

The text modes (40 and 80 columns; 25 lines) use a standard standard 8x8 matrix.

However, the 1000 can select between displaying these characters in an 8x8 matrix (200 lines) or an 8x9 matrix (225 lines).

So normally in text modes, the spacing on the lines is slightly higher and goes into what would be the border region for normal CGA.

refs:
(Tandy 1000SX Tech manual: "Video Controller Chip Specification," pg.3)
(Tandy 1000SX Quick Reference: A19)
 
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