Date   
Re: 8 slot RCA Microboard Chassis

David Schultz
 

On 8/20/19 6:54 AM, gregory simmons via Groups.Io wrote:
These are great.  I searched and searched but couldn't find any
backplanes or card guides; now, the group has shown 2 sources, plus some
other creative ideas.  
It isn't like I kept it a secret:

https://groups.io/g/cosmacelf/message/17836

http://home.earthlink.net/~schultdw/1802/backplane/index.html


--
https://web.archive.org/web/20190214181851/http://home.earthlink.net/~david.schultz/
(Web pages available only at the Wayback Machine because Earthlink
terminated that service.)

RC1802 almost working

famousdavispro@...
 

Hi guys, I'm new here.  I built the RC1802 designed by Tor-Eirik Lunde.  I can read the memory just fine, but I can only enter the most significant digit - anything I enter with the right four toggles is ignored.  I'm thinking it's a bad IC (it was made with old stock surplus chips) but I don't know which.  I've tried replacing the MC14495P1, and the 74LS244N but that didn't help.  Anything else you can think to look at?

Re: RetroShield 1802 released

Hank Riley
 

Very nicely done github for this project.  Thanks to you and Erturk.
______________________________________________________________________


On Tuesday, August 20, 2019, 12:05:26 PM EDT, Tor-Eirik Lunde <teblunde@...> wrote:

Re: RetroShield 1802 released

Tor-Eirik Lunde
 

Pushed it to https://github.com/tebl/RetroShield1802-PCB since I already had an account there up and running, it has drafts for a simple README and BOM to get things running, if you want you can pull it and add the contents to your own repo at your convenience. If there's no embarrassing faults introduced in the first version to be fixed, I'll remove it on my end and it'll live on as part of your project.

There's a PCBway order URL on the BOM, it points to the shared project though not sure if it is visible from other accounts until it clears review.

man. 19. aug. 2019 kl. 22:45 skrev Erturk Kocalar <erturkk@...>:

Yes, if you don’t have your own git repo, let’s upload to mine. It’s good to make it available for other people. Please put your name and contact in the design files, and a link to pcbway. I will create a subdirectory for you (and designs from others).

 

Thanks,

Erturk

 

Sent from Mail for Windows 10

 

From: Tor-Eirik Lunde
Sent: Monday, August 19, 2019 11:43 AM
To: cosmacelf@groups.io
Subject: Re: [cosmacelf] RetroShield 1802 released

 

Haven't sent it off yet, I'll add the pin somewhere first - I'll share the project on pcbway when I get the board submitted.

 

I can push the kicad files to github if you or someone else want to refine it/fix my mess, but as it's your baby it's up to you if you want them there or not.

 

man. 19. aug. 2019, 18:25 skrev Erturk Kocalar <erturkk@...>:

Hi,

 

That looks nice. Prototyping area is good addition.

 

If you haven’t released it yet, I would connect SC0 to a spare GPIO.  I didn’t have a pin for SC0 on the 2x18 header, so it is multiplexed w/ TPB (resistors R7 and R8). I’m counting on Arduino not needing both connected at the same time because it can generate the unconnected one internally if needed.

 

Enjoy,

Erturk

 

From: Tor-Eirik Lunde
Sent: Monday, August 19, 2019 7:24 AM
To: cosmacelf@groups.io
Subject: Re: [cosmacelf] RetroShield 1802 released

 

Nice work, looking forward to testing it out in practice. Don't really trust any of my breadboards with 5+ cables so willl be waiting for the slow boat-

 

 

fre. 16. aug. 2019 kl. 22:36 skrev Erturk Kocalar <erturkk@...>:

Hi all,

 

I know it would never feel like the real thing but if there is any use for any purpose or anybody, I released the 1802 version of RetroShield.  If one is familiar with Arduino Mega and have a 1802 chip, it should be easy to bread-board it in one night. Schematics and Arduino code are available here.

 

https://gitlab.com/8bitforce/retroshield1802

 

Currently, it runs a combination of MCSMP, Tiny BASIC and RCA BASIC3 (combinations of two, and even all three). I also got the IDIOT monitor working, but need to do clean-up in SW and get permission from Lee before releasing it publicly.

 

I owe huge thank you to i) Chuck for helping with the MCSMP binary images, documentation and answering questions, ii) Lee for helping w/ hardware details earlier on.  Arduino software prints credit to everybody involved and provides a link to Lee’s website for membership card. Hopefully we get more 1802’s working.

 

I found another monitor, Dave’s monitor, that I got permission to use so that’ll be next in a few weeks. This is the link.

https://sites.google.com/site/walztronix/electronics/1802-projects

 

I want to switch tracks to other processors little bit (2650 and 4004), but for 1802, I got permission to use STG1681 design files so that’ll be something to work on down the road.

 

Thank you for all your help. I already forgot about 8031 and 8085, but I will continue to play with 1802 for awhile 😊

 

Erturk

Sent from Mail for Windows 10

 

 

 

Re: 8 slot RCA Microboard Chassis

gregory simmons
 

These are great.  I searched and searched but couldn't find any backplanes or card guides; now, the group has shown 2 sources, plus some other creative ideas.  

On Monday, August 19, 2019, 01:07:17 AM EDT, somaspack via Groups.Io <somaspack@...> wrote:


I have 5-card backplanes PCB's available, two flavors available as shown. $5 ea + shipping. I also have the correct edge cards with guide rails for these $15 ea.  Bunch of other Microboard related stuff including System 1 CPU, RAM/ROM, protoboards. Please contact me via email. Thanks!

Scott
somaspack@...

Re: RetroShield 1802 released

Erturk Kocalar
 

Yes, if you don’t have your own git repo, let’s upload to mine. It’s good to make it available for other people. Please put your name and contact in the design files, and a link to pcbway. I will create a subdirectory for you (and designs from others).

 

Thanks,

Erturk

 

Sent from Mail for Windows 10

 

From: Tor-Eirik Lunde
Sent: Monday, August 19, 2019 11:43 AM
To: cosmacelf@groups.io
Subject: Re: [cosmacelf] RetroShield 1802 released

 

Haven't sent it off yet, I'll add the pin somewhere first - I'll share the project on pcbway when I get the board submitted.

 

I can push the kicad files to github if you or someone else want to refine it/fix my mess, but as it's your baby it's up to you if you want them there or not.

 

man. 19. aug. 2019, 18:25 skrev Erturk Kocalar <erturkk@...>:

Hi,

 

That looks nice. Prototyping area is good addition.

 

If you haven’t released it yet, I would connect SC0 to a spare GPIO.  I didn’t have a pin for SC0 on the 2x18 header, so it is multiplexed w/ TPB (resistors R7 and R8). I’m counting on Arduino not needing both connected at the same time because it can generate the unconnected one internally if needed.

 

Enjoy,

Erturk

 

From: Tor-Eirik Lunde
Sent: Monday, August 19, 2019 7:24 AM
To: cosmacelf@groups.io
Subject: Re: [cosmacelf] RetroShield 1802 released

 

Nice work, looking forward to testing it out in practice. Don't really trust any of my breadboards with 5+ cables so willl be waiting for the slow boat-

 

 

fre. 16. aug. 2019 kl. 22:36 skrev Erturk Kocalar <erturkk@...>:

Hi all,

 

I know it would never feel like the real thing but if there is any use for any purpose or anybody, I released the 1802 version of RetroShield.  If one is familiar with Arduino Mega and have a 1802 chip, it should be easy to bread-board it in one night. Schematics and Arduino code are available here.

 

https://gitlab.com/8bitforce/retroshield1802

 

Currently, it runs a combination of MCSMP, Tiny BASIC and RCA BASIC3 (combinations of two, and even all three). I also got the IDIOT monitor working, but need to do clean-up in SW and get permission from Lee before releasing it publicly.

 

I owe huge thank you to i) Chuck for helping with the MCSMP binary images, documentation and answering questions, ii) Lee for helping w/ hardware details earlier on.  Arduino software prints credit to everybody involved and provides a link to Lee’s website for membership card. Hopefully we get more 1802’s working.

 

I found another monitor, Dave’s monitor, that I got permission to use so that’ll be next in a few weeks. This is the link.

https://sites.google.com/site/walztronix/electronics/1802-projects

 

I want to switch tracks to other processors little bit (2650 and 4004), but for 1802, I got permission to use STG1681 design files so that’ll be something to work on down the road.

 

Thank you for all your help. I already forgot about 8031 and 8085, but I will continue to play with 1802 for awhile 😊

 

Erturk

Sent from Mail for Windows 10

 

 

 

Re: RetroShield 1802 released

Tor-Eirik Lunde
 

Haven't sent it off yet, I'll add the pin somewhere first - I'll share the project on pcbway when I get the board submitted.

I can push the kicad files to github if you or someone else want to refine it/fix my mess, but as it's your baby it's up to you if you want them there or not.

man. 19. aug. 2019, 18:25 skrev Erturk Kocalar <erturkk@...>:

Hi,

 

That looks nice. Prototyping area is good addition.

 

If you haven’t released it yet, I would connect SC0 to a spare GPIO.  I didn’t have a pin for SC0 on the 2x18 header, so it is multiplexed w/ TPB (resistors R7 and R8). I’m counting on Arduino not needing both connected at the same time because it can generate the unconnected one internally if needed.

 

Enjoy,

Erturk

 

From: Tor-Eirik Lunde
Sent: Monday, August 19, 2019 7:24 AM
To: cosmacelf@groups.io
Subject: Re: [cosmacelf] RetroShield 1802 released

 

Nice work, looking forward to testing it out in practice. Don't really trust any of my breadboards with 5+ cables so willl be waiting for the slow boat-

 

 

fre. 16. aug. 2019 kl. 22:36 skrev Erturk Kocalar <erturkk@...>:

Hi all,

 

I know it would never feel like the real thing but if there is any use for any purpose or anybody, I released the 1802 version of RetroShield.  If one is familiar with Arduino Mega and have a 1802 chip, it should be easy to bread-board it in one night. Schematics and Arduino code are available here.

 

https://gitlab.com/8bitforce/retroshield1802

 

Currently, it runs a combination of MCSMP, Tiny BASIC and RCA BASIC3 (combinations of two, and even all three). I also got the IDIOT monitor working, but need to do clean-up in SW and get permission from Lee before releasing it publicly.

 

I owe huge thank you to i) Chuck for helping with the MCSMP binary images, documentation and answering questions, ii) Lee for helping w/ hardware details earlier on.  Arduino software prints credit to everybody involved and provides a link to Lee’s website for membership card. Hopefully we get more 1802’s working.

 

I found another monitor, Dave’s monitor, that I got permission to use so that’ll be next in a few weeks. This is the link.

https://sites.google.com/site/walztronix/electronics/1802-projects

 

I want to switch tracks to other processors little bit (2650 and 4004), but for 1802, I got permission to use STG1681 design files so that’ll be something to work on down the road.

 

Thank you for all your help. I already forgot about 8031 and 8085, but I will continue to play with 1802 for awhile 😊

 

Erturk

Sent from Mail for Windows 10

 

 

Re: RetroShield 1802 released

Erturk Kocalar
 

Hi,

 

That looks nice. Prototyping area is good addition.

 

If you haven’t released it yet, I would connect SC0 to a spare GPIO.  I didn’t have a pin for SC0 on the 2x18 header, so it is multiplexed w/ TPB (resistors R7 and R8). I’m counting on Arduino not needing both connected at the same time because it can generate the unconnected one internally if needed.

 

Enjoy,

Erturk

 

From: Tor-Eirik Lunde
Sent: Monday, August 19, 2019 7:24 AM
To: cosmacelf@groups.io
Subject: Re: [cosmacelf] RetroShield 1802 released

 

Nice work, looking forward to testing it out in practice. Don't really trust any of my breadboards with 5+ cables so willl be waiting for the slow boat-

 

 

fre. 16. aug. 2019 kl. 22:36 skrev Erturk Kocalar <erturkk@...>:

Hi all,

 

I know it would never feel like the real thing but if there is any use for any purpose or anybody, I released the 1802 version of RetroShield.  If one is familiar with Arduino Mega and have a 1802 chip, it should be easy to bread-board it in one night. Schematics and Arduino code are available here.

 

https://gitlab.com/8bitforce/retroshield1802

 

Currently, it runs a combination of MCSMP, Tiny BASIC and RCA BASIC3 (combinations of two, and even all three). I also got the IDIOT monitor working, but need to do clean-up in SW and get permission from Lee before releasing it publicly.

 

I owe huge thank you to i) Chuck for helping with the MCSMP binary images, documentation and answering questions, ii) Lee for helping w/ hardware details earlier on.  Arduino software prints credit to everybody involved and provides a link to Lee’s website for membership card. Hopefully we get more 1802’s working.

 

I found another monitor, Dave’s monitor, that I got permission to use so that’ll be next in a few weeks. This is the link.

https://sites.google.com/site/walztronix/electronics/1802-projects

 

I want to switch tracks to other processors little bit (2650 and 4004), but for 1802, I got permission to use STG1681 design files so that’ll be something to work on down the road.

 

Thank you for all your help. I already forgot about 8031 and 8085, but I will continue to play with 1802 for awhile 😊

 

Erturk

Sent from Mail for Windows 10

 

 

Re: Hex LED/keypad (was: Group member looking for Elf computer related printed circuit boards or PC board CAD files)

Lee Hart
 

Hi Chuck,

I can't tell what post you are referring to. I get my posts as regular emails, and there was no link to "this".

COSMACally yours,
Lee Hart
-----Original Message-----
From: cmdrcosmac
Sent: Aug 19, 2019 1:10 AM
To: cosmacelf@groups.io
Subject: Re: [cosmacelf] Hex LED/keypad (was: Group member looking for Elf computer related printed circuit boards or PC board CAD files)

Hi Lee,

I've been reading the older Group posts and came upon this. Has it ever been posted to the Group?
It seems that it may be a viable substitute for the 74C922, which is getting hard to get
Thanks,
-Chuck

--
Excellence does not require perfection. -- Henry James
--
Lee A. Hart http://www.sunrise-ev.com

Re: RetroShield 1802 released

Tor-Eirik Lunde
 

Nice work, looking forward to testing it out in practice. Don't really trust any of my breadboards with 5+ cables so willl be waiting for the slow boat-

Retroshield1802-PCB.png

fre. 16. aug. 2019 kl. 22:36 skrev Erturk Kocalar <erturkk@...>:

Hi all,

 

I know it would never feel like the real thing but if there is any use for any purpose or anybody, I released the 1802 version of RetroShield.  If one is familiar with Arduino Mega and have a 1802 chip, it should be easy to bread-board it in one night. Schematics and Arduino code are available here.

 

https://gitlab.com/8bitforce/retroshield1802

 

Currently, it runs a combination of MCSMP, Tiny BASIC and RCA BASIC3 (combinations of two, and even all three). I also got the IDIOT monitor working, but need to do clean-up in SW and get permission from Lee before releasing it publicly.

 

I owe huge thank you to i) Chuck for helping with the MCSMP binary images, documentation and answering questions, ii) Lee for helping w/ hardware details earlier on.  Arduino software prints credit to everybody involved and provides a link to Lee’s website for membership card. Hopefully we get more 1802’s working.

 

I found another monitor, Dave’s monitor, that I got permission to use so that’ll be next in a few weeks. This is the link.

https://sites.google.com/site/walztronix/electronics/1802-projects

 

I want to switch tracks to other processors little bit (2650 and 4004), but for 1802, I got permission to use STG1681 design files so that’ll be something to work on down the road.

 

Thank you for all your help. I already forgot about 8031 and 8085, but I will continue to play with 1802 for awhile 😊

 

Erturk

Sent from Mail for Windows 10

 

Re: Hex LED/keypad (was: Group member looking for Elf computer related printed circuit boards or PC board CAD files)

cmdrcosmac
 

Hi Lee,

I've been reading the older Group posts and came upon this. Has it ever been posted to the Group?
It seems that it may be a viable substitute for the 74C922, which is getting hard to get
Thanks,
-Chuck

Re: 8 slot RCA Microboard Chassis

somaspack
 

I have 5-card backplanes PCB's available, two flavors available as shown. $5 ea + shipping. I also have the correct edge cards with guide rails for these $15 ea.  Bunch of other Microboard related stuff including System 1 CPU, RAM/ROM, protoboards. Please contact me via email. Thanks!

Scott
somaspack@...

Re: 8 slot RCA Microboard Chassis

Dave Ruske
 

The group is, so far, using only a little of its available 10 GB space, so there should be no problem with hosting these here.

Dave

On Aug 18, 2019, at 9:17 AM, gregory simmons via Groups.Io <gregorysimmons@...> wrote:

I've posted the pictures of the components and disassembly of the MSI808 8-slot card cage in a new folder "Microboard Card Cage MSI808 Components and Disassembly".  
Options, descriptions, and measurements of components can be found in the "1982 RCA Microboards" document (available on bitsavers), pages 402-413. 

There is a possible concern... these pictures are taking up about 190 MB of group file space.  If this is too much, please delete them and let me know, and I can put them on my gdrive and provide a link to them that way.

Re: 8 slot RCA Microboard Chassis

gregory simmons
 

I've posted the pictures of the components and disassembly of the MSI808 8-slot card cage in a new folder "Microboard Card Cage MSI808 Components and Disassembly".  
Options, descriptions, and measurements of components can be found in the "1982 RCA Microboards" document (available on bitsavers), pages 402-413. 

There is a possible concern... these pictures are taking up about 190 MB of group file space.  If this is too much, please delete them and let me know, and I can put them on my gdrive and provide a link to them that way.

Re: 8 slot RCA Microboard Chassis

gregory simmons
 

David, thank you for sharing that link.  I had been looking for a source of backplanes.

In my case, the chassis I saw was 8 slot... I didn't have an option for a smaller one.  However, I agree with you that I probably won't ever fill up all 8 slots!


On Saturday, August 17, 2019, 11:51:57 AM EDT, David Schultz <david.schultz@...> wrote:


On 8/15/19 10:24 AM, gregory simmons via Groups.Io wrote:
> I recently purchased an 8-slot RCA Microboard Chassis on eBay.  It
> includes the backplane.  It's beautiful, heavy, and solid as a rock.  If
> there's any interest, I'd be glad to disassemble it and post photos of
> its constituent pieces, including the backplane, in case someone wanted
> to use the photos to make a template to create their own microboard
> chassis.  -greg/ab8im  

8 slots is kind of overkill when you can get a 512KB CMOS SRAM. I
decided that 3 was good enough for my needs:

https://oshpark.com/shared_projects/OC8TKQk6


--
https://web.archive.org/web/20190214181851/http://home.earthlink.net/~david.schultz/
(Web pages available only at the Wayback Machine because Earthlink
terminated that service.)



Re: 8 slot RCA Microboard Chassis

David Schultz
 

On 8/15/19 10:24 AM, gregory simmons via Groups.Io wrote:
I recently purchased an 8-slot RCA Microboard Chassis on eBay.  It
includes the backplane.  It's beautiful, heavy, and solid as a rock.  If
there's any interest, I'd be glad to disassemble it and post photos of
its constituent pieces, including the backplane, in case someone wanted
to use the photos to make a template to create their own microboard
chassis.  -greg/ab8im  
8 slots is kind of overkill when you can get a 512KB CMOS SRAM. I
decided that 3 was good enough for my needs:

https://oshpark.com/shared_projects/OC8TKQk6


--
https://web.archive.org/web/20190214181851/http://home.earthlink.net/~david.schultz/
(Web pages available only at the Wayback Machine because Earthlink
terminated that service.)

Re: 8 slot RCA Microboard Chassis

bill rowe
 

that's an excellent idea. 


From: cosmacelf@groups.io <cosmacelf@groups.io> on behalf of Lee Hart <leeahart@...>
Sent: August 16, 2019 10:47 PM
To: cosmacelf@groups.io <cosmacelf@groups.io>
Subject: Re: [cosmacelf] 8 slot RCA Microboard Chassis
 
chuck cmdrcosmac wrote:
> ... I found that a card-cage new was WAY over my budget. Card-
> edge connectors aren't much cheaper than the DIN connectors, and
> proto-boards with edge fingers aren't cheap.
>
> An important consideration is ease of debugging. You must be able to
> get instrument probes anywhere on the board under test. This is where
> card cages and backplanes are inconvenient.

Here's a scheme I have used since my very earliest micro (a Mark-8):

Use ribbon cable as your "bus" instead of a motherboard full of
connectors. Crimp a female IDC (Insulation Displacement Connector) onto
the ribbon cable every inch or two.

Put matching right-angle male headers on each of your PC boards.

The cards can all be placed in a card rack to hold them parallel to each
other. Or, you can use long screws and spacers to hold them apart.

For servicing and troubleshooting, the cards can be opened like pages in
a book. The ribbon cable is flexible enough so you can get at both sides
of any card, even while it's connected to the rest of the system.

--
Whether we or our politicians know it or not, Nature is party to all
our deals and decisions, and she has more votes, a longer memory,
and a sterner sense of justice than we do. -- Wendell Berry
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com




--
Bill Rowe
Olduino - an arduino for the first of us
https://olduino.wordpress.com/about-2/about/

Re: 8 slot RCA Microboard Chassis

cmdrcosmac
 

 Lee,
Thank you for your response. I had thought of the ribbon cable concept.
Unless you use the proper tooling to crimp on the connectors, the connections
may not be reliable. Where I used to work we used a lot of IDC/ribbon stuff.
it sometimes caused trouble. I didn't want to buy the tooling. ($$)
 Thinking back, there are suppliers who will make up short runs of this stuff.
Samtec comes to mind. Actually this is probably the cheapest way to do a backplane.
 Space the connectors to fit a card cage if needed, and one on a longer "tail"
for accessibility.
-Chuck

Re: 8 slot RCA Microboard Chassis

Lee Hart
 

chuck cmdrcosmac wrote:
... I found that a card-cage new was WAY over my budget. Card-
edge connectors aren't much cheaper than the DIN connectors, and
proto-boards with edge fingers aren't cheap.

An important consideration is ease of debugging. You must be able to
get instrument probes anywhere on the board under test. This is where
card cages and backplanes are inconvenient.
Here's a scheme I have used since my very earliest micro (a Mark-8):

Use ribbon cable as your "bus" instead of a motherboard full of connectors. Crimp a female IDC (Insulation Displacement Connector) onto the ribbon cable every inch or two.

Put matching right-angle male headers on each of your PC boards.

The cards can all be placed in a card rack to hold them parallel to each other. Or, you can use long screws and spacers to hold them apart.

For servicing and troubleshooting, the cards can be opened like pages in a book. The ribbon cable is flexible enough so you can get at both sides of any card, even while it's connected to the rest of the system.

--
Whether we or our politicians know it or not, Nature is party to all
our deals and decisions, and she has more votes, a longer memory,
and a sterner sense of justice than we do. -- Wendell Berry
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com

Re: 8 slot RCA Microboard Chassis

cmdrcosmac
 

My $0.02 worth...

I did a backplane expander for my SuperElf. It's a piece of perf-board extending
from the the rear of the Elf board. A DIN 50-pin female vertical-mount connector,
 DigiKey H11206-ND  is soldered on the bottom side of the Elf. Its mate, DK H11166-ND,
is mounted on the top of the perf-board. 4 female connectors, D-K A32831-ND are mounted
on the top of the Perf-board an inch apart.
 The Elf and the backplane are mounted on a board, on standoffs such that the Elf plugs
into the backplane. The addon cards have the DK A32297-ND mounted at one edge.
There is no card cage, so the size of the boards is not constrained.
This is all point-to-point wired.
 There may be pictures of this in the "Commander Cosmac" files
section.
 
 When designing this, I found that a card-cage new was WAY over my budget. Card-
edge connectors aren't much cheaper than the DIN connectors, and proto-boards with
edge fingers aren't cheap. This arrangement is cheap and flexible.
 
 An important consideration is ease of debugging. You must be able to get instrument
probes anywhere on the board under test. This is where card cages and backplanes are
inconvenient. With a cage, you need an extender to get the card out where you can get
at it and it's still standing up. With an open backplane you may have to rearrange
the cards so that you can get at the one you are working on.
 
 If I were making another backplane I would have one right-angle card connector on
the side, so a card under test would lay flat and unobstructed.
 As it is, my system has been very reliable.
-- Chuck