1088XEL Atari ITX Motherboard DIY Builders Thread

[+DrVenkman]

I did it. I successfully removed the 90 degree headers on my U1MB. Whew.

 

 

 

HOWEVER ...

 

In the interest of full disclosure, and so that my failure serves as a learning experience for others, let me add that I successfully removed the headers on ONE of my U1MB's, and not the one that came with my kit from MacRorie, alas. That one ... did not fare so well. Let me explain my failure and then how I learned from it and what I did instead the second time.

 

So I have watched Jon's video on YouTube a few times and thought it seemed pretty straightforward. Cut the plastic bits apart on the existing headers, push them off the metal pins, add flux to both sides of the board, heat each pin and pull it out when the solder melts. Unfortunately, my liquid flux (MG Chem stuff I've used for awhile now - magic on most solder) didn't seem to do all that great on the lead-free crap on these U1MBs. But I digress ... I started on the 30 pin header with confidence - I've seen it done and I'm generally good at learning by doing and watching. So ... Once I saw the solder glisten, I began slowly removing the pin and it took awhile, but I got the pin out. Along with half of the solder pad. :\ It looked salvageable so I continued. The next two pins came out reasonable well - I waited longer on the heat and that helped. But the fourth pin took the entire via right out of the board. Well, shit. At that point I still had hopes of trying to salvage the board and I'd seen Jon do this on video. So I persisted. I added a bit more flux, used a couple seconds more heat and it seemed to help. The rest of the pins went reasonably well until I got to pin 29, which broke right off inside the via and no matter what I tried with the solder sucker, I could not get it out. The pad got damaged there too before I just gave up on it. And upon further inspection, I realized along the way ANOTHER pad had gotten stuck to a pin and disappeared off the board. Jebus, what a mess.

 

At this point I remembered someone's kind offer (Stephen's?) to do this part of the job for a nominal fee ... But I was angry at myself and remembered I have two other U1MB's in the house. One lives in my daily driver 1200XL and is sacrosanct. But my PREVIOUS daily driver is an 800XL presently sitting on a shelf pending some rearrangement of stuff in the house in the coming months. So having pretty well screwed up the single most expensive part of this build, I decided I could at least use it as a learning experience. I removed the board from my vice, flipped it around and began on the 20 pin side. Again I cut the plastic bits off the pin but this time, not only did I add flux to both sides, I added a drop of 60/40 leaded solder to the bottom of each pin to melt the crap used by whatever board assembly house Lotharek gets these from. Another drop on the iron, grasp the pin with my tweezers in the other hand, heat the pin and ... VOILA! Pulled right out perfectly cleanly. Unfortunately the extra solder leaves the hole filled but at least it's nice leaded solder. I easily removed all 20 pins from this side, then cleaned out the holes with a touch of the iron and my solder sucker. THAT side came out utterly perfectly with no pad damage at all on either side of the board.

 

So I took a deep breath, grabbed that 800XL off the shelf, opened it up, removed the U1MB and placed it into the vice ... An hour or so later, I'm ready to fit the header pins to the board, place it onto the extra-tall female headers I cut yesterday and solder it up.

 

That might be tonight or it might not. I kinda wanna just emotionally recover from all this first, lol.

 

 

[+mytek]

Yep adding new solder always helps. and is pretty much mandatory on boards that have been machined soldered and cleaned. Sorry to hear about the destruction of the first board .

 

I also use good old rosin flux, which although leaves a very sticky residue, does a great job of getting things to flow. Then leaving the flux residue in place, I install and solder the new headers. Finally a bit of Acetone on Q-tips removes the left over rosin flux.

[Brentarian]

DrVenkman,

The bright side is at least your first U1MB is salvagable. Your second attempt looks great and much better than what mine looks like. I guess practice makes perfect!

[+DrVenkman]

My flux is rosin-based and generally works great on everything else I've used it on. The sticky leftover mess cleans up easily with isopropyl alcohol and Q-tip or cloth. The pics above are after I've cleaned things up. Anyway, it was an expensive lesson on how to do this on a U1MB or - I suppose - any other modern upgrade board. And how NOT to do it, which is why I posted all the gory details of my screw-up.

 

I *HATE* to give up when I've made a mistake, and I had those other two U1MB's in the house, so it made experimenting on the other end of the first board worthwhile. Now I'm ready to fit everything all together and solder it in proper alignment, but after sitting down and eating dinner, I think it's time for a celebratory beer and maybe another to mourn my now-bollixed U1MB, which will never live to power an A8 machine. Requiescat in pace, U1MB. We hardly knew ye.

 

DrVenkman,
The bright side is at least your first U1MB is salvagable. Your second attempt looks great and much better than what mine looks like. I guess practice makes perfect!

 

​There's a broken bit of pin jammed up in the remains of the pin 29 hole ... Not really sure I can salvage that. For the other two pins I could solder jumpers from the new header pin to wherever the trace leads but pin 29 is a disastrous mess. I didn't want to make anyone sick so I won't post a photo.

[+Firedawg]

Hang in there DrV. It is a journey and a process to work towards a working board. You will get there just keep methodically adding your components and don't rush especially if your tired as that is when errors creep in.

 

Mike

[+DrVenkman]

Hang in there DrV. It is a journey and a process to work towards a working board. You will get there just keep methodically adding your components and don't rush especially if your tired as that is when errors creep in.

 

Mike

 

Yep. I get that. The irony is I screwed up the U1MB around mid-day today, within the first 20 minutes or so of starting work, lol! The second U1MB, which went just swimmingly, was late this afternoon after I'd worked through what I did wrong and how to do it better the next time. Ah, well. Life itself is just a long process of making mistakes, learning from them, and doing better the next time.

 

At least now I have a clean, ready-to-go U1MB for my 1088XEL build, and my regular U1MB-equipped 1200XL is still ready to rock and roll. I'm only "down" a spare U1MB-equipped 800XL. And at that, I can still reinstall the original OS and MMU if I want to set it up again until I get another U1MB someday. I gather Candle is working on an updated version anyway, along with the Incognito2 (which I want for one of my 800's). The life of an Atari tinkerer is rarely boring unless he's broke, right?

[+mytek]

Hey DrV at least your 1st board stands a chance of possibly working once again by jumpering stuff. I destroyed two U1MB's in a matter of seconds this year, both because of stupid mistakes. One because I had unplugged a header and then when plugging it back in I was off by one pin, and the other was when I was probing the MPBI with the system powered up and I slipped touching the wrong pin in the process. Both incidents resulted in frying chips.

 

Developing the 1088XEL has cost me more then I ever dreamed possible .

[hunter44102]

Preparing to do this project! Not looking forward to the desoldering the U1MB but will save it for later.

[+DrVenkman]

Preparing to do this project! Not looking forward to the desoldering the U1MB but will save it for later.

 

It’s been great so far until today. Read my gory post above, learn from my mistake, add leaded solder before you remove the pins. It’ll be fine.

[_The Doctor__]

adding the 60 40 solder changes the melting point of the silver bearing solder as they mix to create a new alloy mix... it is an essential technique for reworking boards (especially thin traced cheap quality pcb's) and in fact using the old lead based solder is a must on almost all older electronics as those boards and integrated devices can not handle/tolerate the heat required with todays' alloys very well if at all

Edited January 8, 2018 by _The Doctor__

[+orpheuswaking]

Those headers are the one thing I wont mess with. Luckily I have some friends who will help me with mine when I get my next kit from Macrorie

[+Firedawg]

The more I explore with the 1088XEL the more I'm amazed and in awe of what it is capable of doing. Much much more I have yet to learn. Back to work, my case should be here any day now. Today I'm doing some DB9 to IDC 10 connectors for the joystick ports. Plus, finishing my XEL-CF-][ x 2, Mouse Select, and Status Panel. Good times......

 

[+mytek]

I sent Simius a PM yesterday with a suggestion that Sophia RGB boards destined for the 1088XEL should come with two connectors on the ribbon cable for the RGB output as shown below.

 

 

This way the user has a choice. And especially in cases where something like a 1084D or a SC1435 is to be used, it gives you a much easier interface to come straight out of the DB9.

[Lavalamp]

I sent Simius a PM yesterday with a suggestion that Sophia RGB boards destined for the 1088XEL should come with two connectors on the ribbon cable for the RGB output as shown below.

 

 

This way the user has a choice. And especially in cases where something like a 1084D or a SC1435 is to be used, it gives you a much easier interface to come straight out of the DB9.

 

 

Hi,

 

I'm building a 1088XEL at the moment, and really enjoying it ​ wife now thinks I'm a super nerd just need some clarification on my understanding of things...

 

- The 1088XEL as built uses the ST RGB connector So I can use my ST's RGB /SCART cable?

- The UAV board is used only for composite and SVIDEO output.

- Sofia can be an option if you wanted to add a RGB out as a DB9 (I have one in my A8 at the moment)

- CF is optional for internal storage device, you can still boot via SIO (I have the SIO2SD, 1050 etc)

- Ultimate 1MB is required for the 1088XEL to work.

- I need to source or crimp my own Joystick cables ( length depending on the case I choose to use)

[+MacRorie]

Hi,

 

I'm building a 1088XEL at the moment, and really enjoying it ​ wife now thinks I'm a super nerd just need some clarification on my understanding of things...

 

- The 1088XEL as built uses the ST RGB connector So I can use my ST's RGB /SCART cable?

Yes, this is possible. You need to make sure the pinouts are correct.

- The UAV board is used only for composite and SVIDEO output.

True. You might want this as a fall back, especially when installing other video options. It is easier to verify operation with stock video rather than VBXE or Sophia.

- Sofia can be an option if you wanted to add a RGB out as a DB9 (I have one in my A8 at the moment)

You can also route the RGB through the 13pin DIN connector (ST Monitor)

- CF is optional for internal storage device, you can still boot via SIO (I have the SIO2SD, 1050 etc)

Or the SIO2PC-type option if you have one of those installed

- Ultimate 1MB is required for the 1088XEL to work.

That is correct. If you wish to use the CF option, you will need to get FJC's firmware for the 1088XEL

- I need to source or crimp my own Joystick cables ( length depending on the case I choose to use)

Yes, that is true.

[+mytek]

I'm building a 1088XEL at the moment, and really enjoying it ​ wife now thinks I'm a super nerd just need some clarification on my understanding of things...

 

- The 1088XEL as built uses the ST RGB connector So I can use my ST's RGB /SCART cable?

- The UAV board is used only for composite and SVIDEO output.

- Sofia can be an option if you wanted to add a RGB out as a DB9 (I have one in my A8 at the moment)

- CF is optional for internal storage device, you can still boot via SIO (I have the SIO2SD, 1050 etc)

- Ultimate 1MB is required for the 1088XEL to work.

- I need to source or crimp my own Joystick cables ( length depending on the case I choose to use)

 

I hope your 1088XEL journey is a fun and enjoyable one.

 

To answer your questions...

 

- The 1088XEL as built uses the ST RGB connector So I can use my ST's RGB /SCART cable?

 

First of all just to be clear, there is NO built-in circuitry to generate RGB, that is a function of either an add-on board such as VBXE or Sophia. The DIN-13 connector is a convenience that can be utilized to interface one of those add-on video boards to an SC12224 ST RGB monitor. Was never intended to support an ST to SCART cable, although I am looking at ways to make that possible, but no guarantee that it will out of the box.

 

- The UAV board is used only for composite and SVIDEO output.

 

Yes that is true.

 

- Sofia can be an option if you wanted to add a RGB out as a DB9 (I have one in my A8 at the moment)

 

Yes.

 

- CF is optional for internal storage device, you can still boot via SIO (I have the SIO2SD, 1050 etc)

 

Yes.

 

- Ultimate 1MB is required for the 1088XEL to work.

 

Yes.

 

- I need to source or crimp my own Joystick cables ( length depending on the case I choose to use)

 

Yes.

 

 

EDIT: I guess two people answering is better than one

[+DrVenkman]

The more I explore with the 1088XEL the more I'm amazed and in awe of what it is capable of doing. Much much more I have yet to learn. Back to work, my case should be here any day now. Today I'm doing some DB9 to IDC 10 connectors for the joystick ports. Plus, finishing my XEL-CF-][ x 2, Mouse Select, and Status Panel. Good times......

 

db9cblidc.jpg

 

Fantastic. A few of those parts will make their way into my own shopping cart somewhere down the line. Having never crimped these kinds of cables myself, do either of those connectors require a crimping tool or do you just snap them closed over the end of the cable and the conductors pierce the insulation?

 

[Lavalamp]

 

I hope your 1088XEL journey is a fun and enjoyable one.

....

EDIT: I guess two people answering is better than one

 

Thanks so much! Pleased to see I do have a handle on this project. yes I'm thoroughly enjoying it and thankyou for producing it, fingers cross I get a booting Machine at the end of it lol

[+mytek]

Fantastic. A few of those parts will make their way into my own shopping cart somewhere down the line. Having never crimped these kinds of cables myself, do either of those connectors require a crimping tool or do you just snap them closed over the end of the cable and the conductors pierce the insulation?

 

Here's a good video showing what to do.

 

https://www.youtube.com/watch?v=4pDRrrpAcGQ

 

If you don't have something like that crimping tool, no problem it can be done in a vice instead, but be sure to use soft jaws or aluminum angle to protect the plastic of the IDC connectors.

[Lavalamp]

You can also route the RGB through the 13pin DIN connector (ST Monitor)

 

 

This is interesting, how best to approach this? Would I pass the ribbon underneath the board and solder the connections to the plugs pins on the underside of the board?

 

 

Oh scratch that I see there's a RGB header next to the GITA, this goes to the RGB port? There's a new Sofia to accommodate this?

 

Edited January 8, 2018 by Lavalamp

[+Firedawg]

 

Fantastic. A few of those parts will make their way into my own shopping cart somewhere down the line. Having never crimped these kinds of cables myself, do either of those connectors require a crimping tool or do you just snap them closed over the end of the cable and the conductors pierce the insulation?

 

 

A crimping tool would be overkill, although I do have one. Gentle use of a Tongue and Groove Pliers would work to press together till you here the click of the lock down. Adjustable Vise Grips would work too with you adjusting them enough to allow for a small compression to lock in place.

 

Edit: You just have to love Michael is so fast with response to questions!!! I should just sit back and work on my 1088XEL;-) Plus he adds videos to his answers. lol

[+mytek]

This is interesting, how best to approach this? Would I pass the ribbon underneath the board and solder the connections to the plugs pins on the underside of the board?

 

I see you already discovered the 5x5 pin RGB-THRU header which is shown connected to the Sophia RGB board here. And yes that routes the RGB signals over to the DIN-13 connector. This works with the standard Sophia RGB board, and just requires an IDC10 connector crimped onto Sophia's video out cable.

[DavidMil]

I got my board in the mail today. I have to say that the only other device that I have seen with such dense components is the 8 bit modulators.

This looks like an interesting project, unfortunately I have several other projects in the works now. I'll start gathering components and in a couple

of weeks I'll start the assembly.

 

Thanks again Michael!

(And MacRorie)!

 

David

Edited January 8, 2018 by DavidMil

[Lavalamp]

So the incorrectly specified 0.1uf capacitor has had far reaching consequences. And as I discovered today it's infected two other projects, the XEL-CF-][ and the JOY2PIC-STIK. So let me tell you the story on how all of this came to be...

 

 

Bummer wished I had seen this in time, mine are already on and wonky, apart from aesthetics I assume this wont cause a problem?

[+mytek]

 

Bummer wished I had seen this in time, mine are already on and wonky, apart from aesthetics I assume this wont cause a problem?

 

Correct. Can be just pushed in as is, which will leave them sitting higher off the board, or take the time to make the dog leg bends in the leads so they sit flat. Functionally all is the same.