1200XL questions!

[leech]

So, just got a 1200XL off eBay.  It came with an ICD R-Time-8, which I am going to guess is dead and needs a battery replacement?

 

The second thing is, it has a RamboXL inside and a switch.  This switch has three toggles, the first two just show the Atari logo, the third is a white screen.  It only has two wires, and goes to a piggybacked chip.

 

Can I guess right that this toggles between the 64kb and RamboXL?  And... dead?

[leech]

@flashjazzcat Thanks to your video online

 I managed to fix the mylar with a little bit of dedication (yeah you're totally right, no matter how hard you try, you're going to rip that fragile thing) but before I did it, the only key that seemed to sort of work was the reset key, and it'd cause the system to crash.  I wasn't aware which button was the self test also, so knowing it was the Help key was great!  I also now know i need to do the chroma fix (I thought it was just the 800XL that Atari forgot to wire that one up...)  So thanks!  Donation coming your way!

[Sugarland]

Congrats on your new 1200XL acquisition! The R-Time-8 is great, too. You can boot the machine to test the toggle differences with RAM. Attached are a couple utilities that may or may not detect it.

 

I see corrosion on the legs of U21 and the chip next to it. Suggest you clean that and apply some deoxit.  The board probably needs a full cleaning/inspection/etc..

 

eXtended RAM test v0.21.0 (2003-09-16)(-XI-)(SK)(en)[128k].txt eXtended RAM test v0.21.0 (2003-09-16)(-XI-)(SK)(en)[128k].xex SysInfo v2.25 (2015-09-05)(Kokoszkiewicz, Konrad)(PL)(en).atr

[leech]

7 minutes ago, Sugarland said:

Congrats on your new 1200XL acquisition! The R-Time-8 is great, too. You can boot the machine to test the toggle differences with RAM. Attached are a couple utilities that may or may not detect it.

 

I see corrosion on the legs of U21 and the chip next to it. Suggest you clean that and apply some deoxit.  The board probably needs a full cleaning/inspection/etc..

 

eXtended RAM test v0.21.0 (2003-09-16)(-XI-)(SK)(en)[128k].txt 1.54 kB · 1 download eXtended RAM test v0.21.0 (2003-09-16)(-XI-)(SK)(en)[128k].xex 2.38 kB · 1 download SysInfo v2.25 (2015-09-05)(Kokoszkiewicz, Konrad)(PL)(en).atr 90.02 kB · 1 download

Sweet!  Will give that a shot in the morning.  I hadn't noticed the corrosion earlier, so far after the mylar fix it has been running pretty well.  The video output quality isn't as good as the 800xl, but maybe I will put the UAV in this instead of using it to fix the composite output in the VBXE'd 130XE.  While I have it apart, I will trace out where the toggle switch goes, and I found the manual for the Rambo XL upgrade, so should be able to figure if the switch goes to that or not. 

 

I played Crownlands on it, and I think that requires 128kb of RAM, and yet it worked in the two switch positions that load...

[Sugarland]

Great to hear it's working! FYI there are some who much prefer to do the supervideo upgrade to the 1200XL since that will utilize it's unique color enhancing circuitry that is absent on all other A8's. Your choice of course. Yes trying an application that requires more than 64KB is a good test, as well.  ICD hardware is highly regarded.

 

My first 1200XL had poor video quality as received. The second has flawless output. Not sure why it varies. Maybe since the second machine is barely used.

[Rybags]

The 2 logo screens... are they different?  From memory there's an alternate 1200XL OS Rom, one shows an (R) near Atari and the other doesn't.

[flashjazzcat]

7 hours ago, leech said:

Donation coming your way!

Sincere thanks! Email coming your way.

[Gunstar]

8 hours ago, Sugarland said:

Great to hear it's working! FYI there are some who much prefer to do the supervideo upgrade to the 1200XL since that will utilize it's unique color enhancing circuitry that is absent on all other A8's. Your choice of course. Yes trying an application that requires more than 64KB is a good test, as well.  ICD hardware is highly regarded.

 

My first 1200XL had poor video quality as received. The second has flawless output. Not sure why it varies. Maybe since the second machine is barely used.

Yes. my 1200XL's picture and especially color saturation is incredible ever since I did the 1200XL specific version of Supervideo 2.1. If you have a 1200XL this is the absolute best upgrade for DIY on the cheap. The 1200XL's chroma boost circuit is fantastic once it's been corrected to work correctly by this upgrade. I have true reds on my PAL 1200XL unit.

[leech]

Where can I find the SuperVideo upgrade?  I looked a bit last night and only saw articles on it

 

Just checked the two switch positions, they both have the same rotating color bars with no (R).

[+Nezgar]

17 hours ago, leech said:

It came with an ICD R-Time-8, which I am going to guess is dead and needs a battery replacement?

I've heard many reports that the original clock chip used in the R-Time8 degrades over time and renders it useless, even with a new battery. I lost my original R-Time8 PCB, so I have no way of personally attesting to this.

 

I had removed it from the shell for BBS use long ago so I could sloppily solder on an external CR123 battery... But all is good now since I still have the shell, I acquired one of macrorie's replacement PCB's, and put it into my old shell so aesthetically and functionally, you'd never know the difference..

[leech]

6 minutes ago, Nezgar said:

I've heard many reports that the original clock chip used in the R-Time8 degrades over time and renders it useless, even with a new battery. I lost my original R-Time8 PCB, so I have no way of personally attesting to this.

 

I had removed it from the shell for BBS use long ago so I could sloppily solder on an external CR123 battery... But all is good now since I still have the shell, I acquired one of macrorie's replacement PCB's, and put it into my old shell so aesthetically and functionally, you'd never know the difference..

Nice!  I did not see an immediate way to open the thing, but I am sure I will get to it eventually.  The 1200 has probably the best design/keyboard out of the 8bits that I own.  Loving it.

[+Nezgar]

42 minutes ago, leech said:

I did not see an immediate way to open the thing, but I am sure I will get to it eventually.

The two halves of the shell are connected together by four posts. Extremely carefully just pry the two halves apart, and it should eventually separate. Use a plastic insert to avoid scuffing the plastic along the seam. The posts will break if flexed so make sure it's kept even as you work them apart.

 

The holes in Macrorie's PCB was actually a little wider than my original shell posts, so I accidentally broke the bottom posts in my shell by foolishly forcing it in... But I secured the shell back together with external screws into holes I drilled instead... Oh well.

 

This post contains pictures of the SpartaDOS X shell, which is the same as the R-Time 8 shell, so you can see where the 4 posts are:

 

[leech]

Oops, went to take it apart again to use some deoxit, and ended up breaking one of the wires of the toggle switch off where it was soldered.  So of course now I have to wonder if it was just not connected well before and the switch was doing nothing.

It does appear from another forum post, that it is connected to the MMU at U14, on pins 17 and 19 (assuming pin one is below the notch). 

Guess I will be soldering that back up, and cleaning some things.  That one chip that is pretty dirty seems to have no label on it as well. 

Pretty sure the only mod in this is the RamboXL. So if I can find the SuperVideo 2.1, I think I will do that one!

[xrbrevin]

1 hour ago, leech said:

if I can find the SuperVideo 2.1

ask and ye shall receive ?

 

SuperVideo 21XL oraz errata.pdf

[BillC]

5 hours ago, leech said:

It does appear from another forum post, that it is connected to the MMU at U14, on pins 17 and 19 (assuming pin one is below the notch).

It appears to me that the twisted wires attach to pins 9 & 10 of the MMU, PIN 10 is ground, and pin 9 is REN which when low disables the OS. Normally this is controlled by PB0(an output of the PIA), the switch would be a method of doing this manually.

[leech]

1 minute ago, BillC said:

It appears to me that the twisted wires attach to pins 9 & 10 of the MMU, PIN 10 is ground, and pin 9 is REN which when low disables the OS. Normally this is controlled by PB0(an output of the PIA), the switch would be a method of doing this manually.

What would be the purpose of disabling the OS though?  Yeahif the pins are counted 1-10 on the bottom and 11-20 on the top, you are correct, 9 and 10. 

It really does look to me though that the only mod is to the memory.  And then this switch.  So if it is the disable OS switch that would leave the non Atari screen being the 'on' toggle for the switch.  Now I wonder if that ICD R-Time Cart is modded.  Was this a typical thing to do?

[BillC]

Just now, leech said:

What would be the purpose of disabling the OS though?  Yeahif the pins are counted 1-10 on the bottom and 11-20 on the top, you are correct, 9 and 10. 

It really does look to me though that the only mod is to the memory.  And then this switch.  So if it is the disable OS switch that would leave the non Atari screen being the 'on' toggle for the switch.  Now I wonder if that ICD R-Time Cart is modded.  Was this a typical thing to do?

I may be wrong, but I believe if a different OS is loaded into the RAM under the OS it would take over when the OS chip is disabled by the switch.

[leech]

6 hours ago, xrbrevin said:

ask and ye shall receive ?

 

SuperVideo 21XL oraz errata.pdf 19.66 MB · 9 downloads

Ha, after looking over that and finding out what needs to be done... I'll probably send it off to someone more capable than myself.  I mean if it were a more common machine, like a 600XL or 800XL, then I might be more inclined to hack around with it (as well as the fact I already have a 600XL gathering dust and for some reason just got another one with the SV mod and 64k already).  Chopping into a 1200XL just seems wrong to me, although it's already modded, I'd rather have someone with much more experience than myself.  Any takers?

[xrbrevin]

@flashjazzcat is the sweeney todd of Ataris around here. he provides a professional service with countless satisfied customers

[leech]

4 hours ago, xrbrevin said:

@flashjazzcat is the sweeney todd of Ataris around here. he provides a professional service with countless satisfied customers

Yeah, I immediately was thinking of him, he upgraded my 130XE and did a wonderful job.  The problem is always shipping costs to the UK from the USA.  I want to say it was like 200 bucks last time, and the 1200XL is a much bigger beast.

I will figure something out.  I may attempt it myself, the output definitely could use some tender care.

I need to find a new monitor too, the little shelf I have everything on is not that deep, and the Dell 2001FP I use for S-Video/Composite has a stupidly large stand that sticks out far enough that the 1200XL doesn fit quite well enough.  Anyone have a favorie model?

[Rybags]

Here's one, I'm not sure we've covered it.

 

The option jumper to force startup to Self Test.  Was this put there to make factory post-manufacturing testing easier?  Or just as a meetoo thing since PCs were using them by that time.

Edited March 25, 2020 by Rybags

[+Stephen]

11 hours ago, leech said:

Ha, after looking over that and finding out what needs to be done... I'll probably send it off to someone more capable than myself.  I mean if it were a more common machine, like a 600XL or 800XL, then I might be more inclined to hack around with it (as well as the fact I already have a 600XL gathering dust and for some reason just got another one with the SV mod and 64k already).  Chopping into a 1200XL just seems wrong to me, although it's already modded, I'd rather have someone with much more experience than myself.  Any takers?

Where are you located?  I can do the repair, but my only concern now is the shutdown. I don't know when I could ship it back to you.  I'm in Ohio and we're not on full lockdown now, but I expect it any day unfortunately.

[leech]

3 hours ago, Stephen said:

Where are you located?  I can do the repair, but my only concern now is the shutdown. I don't know when I could ship it back to you.  I'm in Ohio and we're not on full lockdown now, but I expect it any day unfortunately.

I am in Utah, I could still have it shipped I think.

[jamm]

So, the reason people recommend the SuperVideo upgrade over other options (ClearPic) on the 1200XL is that it maintains that model's unique color-boosting circuitry.  However, according to @bob1200xl (and it's hard to imagine a better authority on the matter), that circuitry only improves RF output:

 

 

Does anyone have first-hand experience comparing SV vs. ClearPic or UAV on a 1200XL that can attest to it being an improvement while using composite or s-video?

 

Edited March 25, 2020 by jamm

[tschak909]

I use a UAV in my 1200XL, and holy crap! it improved video output by leaps and bounds, especially the seperate chroma/luma output!

 

-Thom