My summer project: A colour Stacy

[ube]

Nice work! If you’d like I can make you a firmware for the ubeswitch which lets you use the reset button at power on for setting which mode no boot in.

I’ll send you a unit for free. As a pat on the back.

[derkom]

Nice work! If you’d like I can make you a firmware for the ubeswitch which lets you use the reset button at power on for setting which mode no boot in.

I’ll send you a unit for free. As a pat on the back.

Sure, I can give it a try. I'll send you a PM.

I'm 3D printing a bracket to hold both the picoPSU and the VGA adapter at the rear of the lower drive bay, and I just realised tonight that in order to make VGA adapter work, I'll need to install it in an angle, to force the video cable down right near the motherboard, because there's very little clearance right there, due to the metal bracket on the upper case where the cabling goes to the lid. Looking at the ubeswitch, it seems like it may work without doing that, but I wouldn't really know until I got my hands on one.

Of course, bear in mind that all of this part of the project may go away, depending on how well @Smonson's RGB or HDMI board can be made to work in here.

Here's where I ended up tonight...

IMG_20200705_210426.jpg (166.52 KiB) Viewed 1227 times

Following @Atarian Computing's lead (pun intended), I switched my wiring over to the original power input pins on the board, which I replaced yesterday with the 90° headers. This bracket was printed before I figured out that that angle for the VGA converter won't work. I was poking around a bit tonight with adjusting the angle, and that will solve the clearance issue, but I decided not to print anything new until I acquire my VGA cabling and know the exact size of plug I'm dealing with. (And of course if I stick a ubeswitch in there, that changes everything anyway!)

[Smonson]

Of course, bear in mind that all of this part of the project may go away, depending on how well @Smonson's RGB or HDMI board can be made to work in here.

How much room do you have to work with? The HDMI board made by @Icky is getting ridiculously small these days, it might be the easiest fit once it's available. The only downside is getting the connector to the side of the case.

[derkom]

How much room do you have to work with? The HDMI board made by @Icky is getting ridiculously small these days, it might be the easiest fit once it's available. The only downside is getting the connector to the side of the case.

Vertical space is likely to be the tightest constraint, because I am trying to do all this without irreversible modifications, and without cutting a hole in the bottom of the battery compartment, there's only 14 mm vertical between the motherboard and the bottom of the battery compartment. If I cut the battery compartment, there's acres of space, but I really don't want to do that.

The first CPU relocator I built for the Stacy was pretty involved (mostly full width of the motherboard, and including cutouts for the LCD wiring) and although it didn't work reliably, I did get sufficient experience in KiCad that I am comfortable measuring, designing, and building a relocator for the shifter if necessary. I am looking forward to trying out all of the new video solutions when they become available, both in the Stacy and in the H4, and as long as the board can fit *somewhere*, I can probably figure something out.

Whether or not any of the digital solutions will even work may end up depending on how they end up positioning the image on the screen. With the ADC process through the OSSC, I am afforded a great deal of control over the image processing, which will be helpful in centring and scaling for best fit. Your and @Icky's digital solutions by virtue of their much simpler signal path don't have all those knobs and may turn out simply not to be the right fit for this project. We shall see. On the flipside, the digital solutions may be perfect for @Atarian Computing's project, since he's looking for a pixel perfect panel fit, which is exactly where digital will shine.

[Darklord]

First of all to the OP, well done!

Years ago I played around with a color screen on my STacy, but was
never satisfied with the display so didn't pursue it any further. Maybe
with more/modern choices available, I need to look at it again.

I'm interested in the discussion around the STacy's TOS version. I
ripped it once (can't remember what for at the moment) and sent
it to (IIRC) P.Pera and when he compared it to TOS v1.04 from a
standard ST, he said they were the same.

When I was playing around with that color screen I had, it worked
under the STacy's standard v1.04 as well as in TOS 3.06 with the
Pak 68/k board I have installed. In *both* modes, color was there.

We do know that the STacy has different hardware through, right?

Like the shadow shifter...for example.

Thanks.

[Cyprian]

ST-Book has dedicated TOS.
there you can find commented source code:
http://sarnau.info/atari-st-book-bios-x ... m-listing/


https://www.atari-forum.com/viewtopic.php?t=27704

[derkom]

Years ago I played around with a color screen on my STacy, but was
never satisfied with the display so didn't pursue it any further. Maybe
with more/modern choices available, I need to look at it again.

I did indeed read about your adventures there, and that was part of what made me think about giving it a go. I knew it had been a long time since your work, so maybe there was something better out there now. I don't yet know how good it will eventually look with the correct OSSC settings, but since my goal is not pixel perfection, but merely a good looking colour Stacy, I think it'll be just fine for me.

We do know that the STacy has different hardware through, right?

Like the shadow shifter...for example.

Having spent a lot of time poking through the schematics, I think the shadow chip is the only thing that's really different from an ST. Of course there are bits and pieces like the switch in the video connector, the trackball/mouse switch, and the specialised power hardware, but as for what's actually sitting on the bus, it's really just the shadow, and since its only job is to capture the same data as the shifter and convert it for the LCD, TOS isn't going to care about it or know about it. I think.

I haven't dumped my original TOS chips to compare, but you're not the only one who has said it's identical, and since other TOS versions seem to work fine on the Stacy hardware, I think that theory holds up.

No noteworthy progress lately. I've hit a stage where I'm just spending a lot of time figuring out how to make various things actually fit. They will, but it's a bit of a juggling act. And I'm awaiting the customised ubeswitch generously donated by @ube, so I'm not doing too much fitting work around where the VGA switch is right now, since that'll be coming out.

[Darklord]

Thanks for the updates - and the pictures (we love pictures!).

I understand about trying to get everything "STuffed" into a STacy,
believe you me. I didn't think I was ever going to get my machine
back together after installing the Pak 68/3 board, sheesh. Just
rewiring that internal P/S and moving it into the unused battery
compartment was a real headache for someone like me.

[derkom]

Today I installed the custom ubeswitch donated by @ube (thanks again!) and it switches resolutions as advertised, via the reset switch. Nice and handy!

IMG_20200723_213504.jpg (164.27 KiB) Viewed 1036 times

Also I switched the floppy drive headers to 90° headers to allow space for the CPU relocator board. I received my first run of CPU relocator boards, so first I'll be testing that out with just the 68000, and then see about the TF536 later.

[ube]

Cool! It worked at the first try! Nice work! (Even better, I don't have to do trial and error on my side. )