1088XLD - Custom A8 Computer in 1050 Drive Case

[towmater]

A couple of questions as I approach build-out. Can I use the clock crystal from my donor motherboard? What do I need to do to not use a second Pokey (initially)? Jameco didn’t have a 61512a sram, where do you order these? How does one not use an S2 synth module (never heard of it)?

[+DrVenkman]

You really should have installed all the "flat" low-profile discrete components before all those sockets and especially those big, protruding electrolytic caps and the SIO port. 

 

At any rate, I can't answer your question about the crystal specifically but if you're building an NTSC system, just make sure it outputs the correct NTSC colorburst pulse. To not use the second (right) POKEY, just don't install it. The RAM chip I bought from eBay:

 

https://www.ebay.com/itm/1pcs-UM61512AK-15-64K-X-8-BIT-HIGH-SPEED-CMOS-SRAM-DIP-32-/391377191204?

 

The S2 module is a MIDI wavetable synthesizer music module. You can buy them from SerdaShop in Belgium.

 

 

[+MacRorie]

22 minutes ago, towmater said:

A couple of questions as I approach build-out. Can I use the clock crystal from my donor motherboard? What do I need to do to not use a second Pokey (initially)? Jameco didn’t have a 61512a sram, where do you order these? How does one not use an S2 synth module (never heard of it)?

The Brewing Academy sells every single component you need to build either XEL or XLD.  Just send an email to macrorie@thebrewingacademy.com OR PM me here.

 

-M

[+orpheuswaking]

11 hours ago, towmater said:

A couple of questions as I approach build-out. Can I use the clock crystal from my donor motherboard? What do I need to do to not use a second Pokey (initially)? Jameco didn’t have a 61512a sram, where do you order these? How does one not use an S2 synth module (never heard of it)?

It boggles my mind the number of people building these that haven't at least a passing knowledge of the original posts and what is needed. That way you would know about the synth module and other items. 

[+mytek]

2 hours ago, orpheuswaking said:

It boggles my mind the number of people building these that haven't at least a passing knowledge of the original posts and what is needed. That way you would know about the synth module and other items. 

There's also a BOM complete with vendor links to all the essential items (thanks to Dropcheck), and a very good system schematic on my website (link in my signature).

 

As to the questions...

Quote

Can I use the clock crystal from my donor motherboard?

The answer is yes in most cases. But if I recall correctly, it would have to come from an XL or later system due to physical size differences in the 400/800 series.    Edit: if it's a crystal taken from an NTSC system you'll want to mount it laid over due to it's taller stature as compared to the one called out in the BOM.

 

Quote

How does one not use an S2 synth module (never heard of it)?

The 1088XLD is designed to allow a MIDI Synth Module to plug straight in and be usable with or without the optional Level2 I/O board. The S2 Synth Module, the PIC12F1572 flashed with the MIDI Controller firmware, and the LEVEL2 I/O board are all completely optional. If you don't want them, just leave them out.             Same goes for the Right Pokey, just leave it out of your build if stereo is not required.

 

 

And if the Level2 I/O board is not  a part of your 1088XLD build, then a couple of jumpers are required on header J3, in order to activate the MIDI Synth Module for internal playback only via a suitable Atari 8-bit MIDIMATE compatible player program.

 

 

 

Serda S2 DreamBlaster Module

 

Here's an early test of some prototype hardware using a 1088XEL for testing the Serda S2 MIDI Synth Module. Showing the DIN jack MIDI interface board which incorporates the circuitry later used in the 1088XLD Level2 I/O board, thus allowing connection of external MIDI devices (e.g., keyboard controller), or can be used in a ring configuration with other MIDIMATE equipped systems, including the Atari ST to play a game of MIDI-MAZE.

 

 

[_The Doctor__]

@MacRorie,

maybe a stand out piece of paper with the above links mytek rattled off included with the PCB's would be a good idea, I thought that was something sort of already implied, anything to make the modern day hobbiest launch easy as possible. :)

[+MacRorie]

1 hour ago, _The Doctor__ said:

@MacRorie,

maybe a stand out piece of paper with the above links mytek rattled off included with the PCB's would be a good idea, I thought that was something sort of already implied, anything to make the modern day hobbiest launch easy as possible.

I do not understand what this means.  Every motherboard shipped included a printed BOM with all parts as well as a printout of the motherboard's silkscreen.  The BOM includes links to all parts and references board locations.  

 

-M

[towmater]

3 hours ago, orpheuswaking said:

It boggles my mind the number of people building these that haven't at least a passing knowledge

People act as though the internet is some sort of Rosetta Stone of knowledge and that someone should read 35 pages of documents before daring to ask a simple question. Like, now I'm afraid to ask if there's a PS2 converter for the original keyboard so I can adapt a newly designed housing for an old keyboard? I could Google it and spend an hour going down rabbit holes, or I could just ask here if anyone knows an offhand and immediate answer.

[_The Doctor__]

8 minutes ago, MacRorie said:

I do not understand what this means.  Every motherboard shipped included a printed BOM with all parts as well as a printout of the motherboard's silkscreen.  The BOM includes links to all parts and references board locations.  

 

-M

Understood that.

I referring to what one might call quick sheet.

While I will read anything in front of me from cover to cover and check each item in against the the list, others might not do this.

 

Anything to help the new hobbyist out, and get them going so to speak.

Edited April 28, 2020 by _The Doctor__

[+mytek]

13 minutes ago, towmater said:

I'm afraid to ask if there's a PS2 converter for the original keyboard so I can adapt a newly designed housing for an old keyboard?

Don't be afraid to ask. And I surely hope it wasn't me that made you feel that way, because that wasn't my intention. Anyway to answer your question, I don't believe there was such a thing ever made. Perhaps I should look into doing that at some point.

 

However I know that there was at least one project to take the stock keyboard into USB, although that doesn't help you if you need PS/2 instead.

 

[+Stephen]

15 minutes ago, towmater said:

People act as though the internet is some sort of Rosetta Stone of knowledge and that someone should read 35 pages of documents before daring to ask a simple question. Like, now I'm afraid to ask if there's a PS2 converter for the original keyboard so I can adapt a newly designed housing for an old keyboard? I could Google it and spend an hour going down rabbit holes, or I could just ask here if anyone knows an offhand and immediate answer.

If I understand your question, you want a device that can take an original Atari 8-bit keyboard and make it PS/2 compatible?  I am not aware of anything that can do this.  If I misunderstood, apologies.

[mellis]

35 minutes ago, towmater said:

People act as though the internet is some sort of Rosetta Stone of knowledge and that someone should read 35 pages of documents before daring to ask a simple question. Like, now I'm afraid to ask if there's a PS2 converter for the original keyboard so I can adapt a newly designed housing for an old keyboard? I could Google it and spend an hour going down rabbit holes, or I could just ask here if anyone knows an offhand and immediate answer.

Personally, I would do my own research before asking the other forum users to read it for me, but that's just me.

[+mytek]

I see Stephen and I came up empty on a Atari stock keyboard to PS/2 adapter.

 

As I think about this, it really would make more sense to make a board that would fit in place of the one inside an XEGS keyboard that would do the key scan and conversion. Since that would already give you a stock keyboard in a case, as well as a way to house the adapter. It could be made as a drop-in for that original PCB, so no soldering involved, assuming someone like MacRorie would be interested in selling an assembled version. I could see buying a male-to-male Mini-DIN6 cable, and having a female receptacle on the adapter board. Then it would be just a matter of fishing the cable out through the same hole that the original cable used.

 

XEGS Keyboard

 

XEGS Keyboard Scanning Circuit PCB

 

Male-to-Male Mini-DIN6 Cable

MyCableMart.com

Part #:  MR-PS2-6MM

Cost : $1.80

 

This idea could turn out to be very cool ? .

 

 

[+MacRorie]

3 minutes ago, mytek said:

I see Stephen and I came up empty on a Atari stock keyboard to PS/2 adapter.

 

As I think about this, it really would make more sense to make a board that would fit in place of the one inside an XEGS keyboard that would do the key scan and conversion. Since that would already give you a stock keyboard in a case, as well as a way to house the adapter. It could be made as a drop-in for that original PCB, so no soldering involved, assuming someone like MacRorie would be interested in selling an assembled version. 

 

Sure.  I would have no problem carrying something like this, assuming my daughters--who are currently pulling my hands away from the keyboard and crawling under my chair--allow me to make it.

[towmater]

59 minutes ago, mellis said:

Personally, I would do my own research before asking the other forum users to read it for me, but that's just me.

For some, English is not their first language. For me, dyslexia makes it difficult to read large blocks of text. Someday, we might all be the same. Just joshing you, please don't take offense.

Edited April 28, 2020 by towmater

[+Stephen]

16 minutes ago, mytek said:

I see Stephen and I came up empty on a Atari stock keyboard to PS/2 adapter.

 

As I think about this, it really would make more sense to make a board that would fit in place of the one inside an XEGS keyboard that would do the key scan and conversion. Since that would already give you a stock keyboard in a case, as well as a way to house the adapter. It could be made as a drop-in for that original PCB, so no soldering involved, assuming someone like MacRorie would be interested in selling an assembled version. I could see buying a male-to-male Mini-DIN6 cable, and having a female receptacle on the adapter board. Then it would be just a matter of fishing the cable out through the same hole that the original cable used.

 

XEGS Keyboard

 

XEGS Keyboard Scanning Circuit PCB

 

Male-to-Male Mini-DIN6 Cable

MyCableMart.com

Part #:  MR-PS2-6MM

Cost : $1.80

 

This idea could turn out to be very cool ? .

 

 

People would jump all over that I bet!  Lots of requests / questions about using an Atari keyboard with their 1088 machines for example.

[StickJock]

You would want to modify the XEGS keyboard to add the missing console buttons if you planned on using it on your 1088.  This could be as simple as drilling some holes and putting in some panel-mount push buttons, or as complex as having fancy cutouts with 3-D printed buttons.

[towmater]

7 minutes ago, StickJock said:

You would want to modify the XEGS keyboard to add the missing console buttons if you planned on using it on your 1088.  This could be as simple as drilling some holes and putting in some panel-mount push buttons, or as complex as having fancy cutouts with 3-D printed buttons.

No. No. Just a keystroke sequence please.

[StickJock]

21 minutes ago, towmater said:

No. No. Just a keystroke sequence please.

Nifty idea, but I'm not sure how this would work if you want to have multiple console keys pressed at once or if you want to have console key(s) pressed at the same time as a key gets pressed.  For example, hold Select+Option and press "Q".

Also, if you need to press Select in a game to quickly switch weapons or something, it would not work well to have to type a keystroke sequence.

[+orpheuswaking]

2 hours ago, towmater said:

People act as though the internet is some sort of Rosetta Stone of knowledge and that someone should read 35 pages of documents before daring to ask a simple question. Like, now I'm afraid to ask if there's a PS2 converter for the original keyboard so I can adapt a newly designed housing for an old keyboard? I could Google it and spend an hour going down rabbit holes, or I could just ask here if anyone knows an offhand and immediate answer.

It's not a matter of a google rabbit hole, you can search this very thread directly from within the forum. Being that the MIDI functionality and the S2 synth is a fundamental part of the design it would make sense to know at least the basics before attempting to build (or even buy). 

[+mytek]

1 hour ago, StickJock said:

You would want to modify the XEGS keyboard to add the missing console buttons if you planned on using it on your 1088.  This could be as simple as drilling some holes and putting in some panel-mount push buttons, or as complex as having fancy cutouts with 3-D printed buttons.

Of course I would want to support the XE keyboard's console keys which are already present, and then leave it up to the USER if they want to drill the top of the case and add button tops.

 

 

47 minutes ago, StickJock said:

Nifty idea, but I'm not sure how this would work if you want to have multiple console keys pressed at once or if you want to have console key(s) pressed at the same time as a key gets pressed.  For example, hold Select+Option and press "Q".

Also, if you need to press Select in a game to quickly switch weapons or something, it would not work well to have to type a keystroke sequence.

What I'm in the planning stages for should work the same, because that's presently possible from the PS/2 keyboard, and the completed drop-in adapter board will be speaking PS/2. However it will send out the TK-II PS/2 Function key equivalents (AKI-EMU: F1=HELP, F2=Start, F3=Select, F4=Option, F5=Reset).

 

[flashjazzcat]

Surely the XEGS keyboard sucks? It's puzzling that the virtues of replacing the original Atari keyboard with a PS/2 keyboard were so vigorously extolled on the grounds of vastly improved typing experience, much greater flexibility, etc, and here we are trying to plug the spongy XEGS keyboard into the PS/2 adapter intended for the superior, modern replacement.

 

Anyway: I always thought it was a big mistake leaving the console keys off the detachable XEGS keyboard. When I did finally get hold of an XEGS some years ago, I had ideas about how cool it would be to word process on the machine using the detachable keyboard... until it became clear that I'd have to constantly reach across to the console base unit to press the console keys used by my word processor. An XEGS keyboard with integrated console keys would certainly be an improvement, and I suppose an interesting and ironic proposition when connected to an XEL or XLD machine.

 

EDIT: I suppose there's a stronger argument for using the XEGS keyboard with the XLD than the XEL on the basis of styling alone, although it's obviously a juxtaposition of the XL and XE aesthetics.

 

Edited April 28, 2020 by flashjazzcat
removed repeated word

[+mytek]

8 minutes ago, flashjazzcat said:

Surely the XEGS keyboard sucks? It's puzzling that the virtues of replacing the original Atari keyboard with a PS/2 keyboard were so vigorously extolled on the grounds of vastly improved typing experience, much greater flexibility, etc, and here we are trying to plug the spongy XEGS keyboard into the PS/2 adapter intended for the vastly superior, modern replacement.

Trying to work with what we've got. Unfortunately Atari never produced an XL equivalent to this, which would have been much nicer. However my thinking was to make this adapter board universal in nature, so that either an XE or XL keyboard could be plugged into it. Of course with the XL keyboard you have a dilemma as to what to use for a case, although I suppose a non-working 600XL would suffice .

 

Edit: could make the XE keyboard feel better by installing one of those kits that Best Electronics sells.

 

[flashjazzcat]

11 minutes ago, mytek said:

I suppose a non-working 600XL would suffice

Indeed. All we'd need then is an XEL motherboard which fits in a 600XL case, and the keyboard will then be integral with the base unit.

13 minutes ago, mytek said:

Edit: could make the XE keyboard feel better by installing one of those kits that Best Electronics sells.

Definitely. I never did get hold of one of those 'touch' keyboard spring kits, so I can't speak to their effectiveness. I heard good things about them, though. Unmodified, the XEGS keyboard (like many equivalent XE keyboards with rubber domes under the keys) provides an immensely unsatisfying and almost traumatic typing experience.

[+mytek]

Here's a very simple concept for the adapter board (some parts missing).

 

This has been verified to fit in the XEGS keyboard case and clear the bottom of the keyboard.

 

 

Unfortunately the XL keyboard connector has an entirely different pin-out (why???).

 

Probably have to squeeze in two different connector footprints, one for XE and the other for XL, and move some stuff around.