New hardware revision?

Talk about everything hardware related
Brian
Posts: 2
Joined: Sun Sep 23, 2012 5:54 am

Re: New hardware revision?

Postby Brian » Sun Sep 23, 2012 6:04 am

Hi, Simon,

I'd be interested in purchasing 2 boards, if the price could be brought down to $20 each. Other similar projects are around that level. My biggest concern is the cost and availability of some of the components. Floppy chips can be difficult to find for a reasonable price as well as video controllers. It might be best to offer a group buy option of these components as well.

I would like to see the full 68000 CPU used; I agree with others that moving up to the 020+ increases the complexity to a level that I'm actually not interested in. My goal is to build computers like this that can be designed, constructed, programmed, and (very importantly) understood without having to have a design team.

I look forward to seeing the project develop. The video on YouTube is very cool and the use of EhBasic gives it that old-school flavor. I'm personally a bit more interested in developing a ROM monitor with EhBasic as an option or a loadable program from CF or some such, but it's currently very reminiscent of my first computers (VIC-20).

Regards,

Brian.

simon
Site Admin
Posts: 744
Joined: Thu Sep 13, 2012 9:35 am
Location: Luedenscheid, Germany
Contact:

Re: New hardware revision?

Postby simon » Sun Sep 23, 2012 1:47 pm

Brian wrote:I'd be interested in purchasing 2 boards, if the price could be brought down to $20 each. Other similar projects are around that level. My biggest concern is the cost and availability of some of the components. Floppy chips can be difficult to find for a reasonable price as well as video controllers. It might be best to offer a group buy option of these components as well.


Good to hear. I thought of a group buy of all components as well. But I really can't say how much it will end up. As for the PCB itself it depends on size and quantities. I don't know, if 100 would not be too many boards.

Brian wrote:I would like to see the full 68000 CPU used; I agree with others that moving up to the 020+ increases the complexity to a level that I'm actually not interested in. My goal is to build computers like this that can be designed, constructed, programmed, and (very importantly) understood without having to have a design team.


I agree. At the moment I personally still prefer the MC68008 because of shying away from doing the design changes. :roll: If someone wants to help with that...?
BTW, the way the SID is used makes it difficult to change the 10MHz CPU clock. The E clock is a tenth of the CPU clock. Thus with a 10MHz CPU clock it outputs the necessary 1MHz for the SID.

Simon

simon
Site Admin
Posts: 744
Joined: Thu Sep 13, 2012 9:35 am
Location: Luedenscheid, Germany
Contact:

Re: New hardware revision?

Postby simon » Sun Sep 30, 2012 6:17 pm

Hi,

it seems there is not very much interest in this project. Well, if there is no co-work from the community, I keep programming. I have a Kiwi and a new design is only a nice-to-have for me. ;)



Simon

netwar
Posts: 40
Joined: Mon Sep 17, 2012 5:31 am
Location: North Carolina,United States of America

Re: New hardware revision?

Postby netwar » Tue Oct 02, 2012 8:30 pm

Don't Lose faith so soon! The word needs to be spread around enough.Also be aware of two things
1)This is a retro PC most people aren't nostalgic about it so its a niche audience to begin with
2)Open source projects don't really gain speed until something unique happens or a completed V1.0.0 is out and people review it
You've got users on your forums and you're on Hackaday.com so you do have publicity.To everyone who wants to see this come to fruition you have to spread the word even to people
that aren't into retro stuff but just like making a working kit.This is also good for teachers and parents to show to a Teenage boy/girl if they are into electronics and they want to learn more
about computers!If its the last thing I will not let this die!Also this project could be used in underpriveled schools or countrys aother project that i have the schematics and source for but haven't made it
yet is called humane PC which is based of arduino and its a simple 8 bit computer with commandline for use in developing countries schools.They are just starting to be distributed and its really cool stuff humaneinfo.com/pc.html is there website. Although it isn't this projects initial goal you may be able to get more of a following if you decide to do something like this just a thought (although in america we really need to focus on our own problems $17 trillion in debt and we still pay for other countries issues)

simon
Site Admin
Posts: 744
Joined: Thu Sep 13, 2012 9:35 am
Location: Luedenscheid, Germany
Contact:

Re: New hardware revision?

Postby simon » Fri Oct 05, 2012 9:35 am

Probably you are right. I expected it to be a niche project. And maybe the word isn't just spread enough yet. You are inivited to help spreading. I try to write new software as a video of some demo or game gains more attention. :)
As we said before, a single computer is expensive. Thus I would not consider it for developing countries or underpriviledged schools. But I could still think of people with some kind of electrical knowledge as target. There is a working design which needs some rework. So the project should not be seen as "wait until a new revision is available" but as "what can I do for a next revision". You could call it "experimental archeology". ;)
I am curious how the project evolves. The design files within the internal forum aren't downloaded very often yet. :roll:

Simon :)

netwar
Posts: 40
Joined: Mon Sep 17, 2012 5:31 am
Location: North Carolina,United States of America

Re: New hardware revision?

Postby netwar » Mon Oct 08, 2012 6:05 am

I'll bot a few hundred pc's to do a massivley recursive download for you (Jk :lol: ) ill try and help the spread best i can 8-)

simon
Site Admin
Posts: 744
Joined: Thu Sep 13, 2012 9:35 am
Location: Luedenscheid, Germany
Contact:

Re: New hardware revision?

Postby simon » Tue Oct 09, 2012 2:42 pm

Thank you!

lee
Posts: 12
Joined: Wed Oct 17, 2012 7:33 pm

Re: New hardware revision?

Postby lee » Wed Oct 17, 2012 8:39 pm

BTW is a MC68030 that much harder to work with?

I'd say it's easier than a vanilla 68000. You can make a 68030 circuit that is almost identical to a 68008 design.

I may also be able to source 140 or so 68030s.

I assume, even the A500 keyboard could be used,

I'd opt for PC peripherals as they're just as easy to use and much easier to source.

At the moment I personally still prefer the MC68008 because of shying away from
doing the design changes. If someone wants to help with that...?

I can help with that if needs be.

The E clock is a tenth of the CPU clock. Thus with a 10MHz CPU clock it outputs the necessary 1MHz for the SID.

As long as there is a suitable clock for the SID it shouldn't matter what the 680x0 is run at.

Lee.

lee
Posts: 12
Joined: Wed Oct 17, 2012 7:33 pm

Re: New hardware revision?

Postby lee » Wed Oct 17, 2012 9:20 pm

Other suggestions.

Drop the floppy, SD card support would be more usefull.

Replace the EPROM with FLASH.

Interface the keyboard/mouse directly, not too hard to do.

ISA bus slots for all my classic ISA CPU cards so I finally have a home for things like this.

Lee.

simon
Site Admin
Posts: 744
Joined: Thu Sep 13, 2012 9:35 am
Location: Luedenscheid, Germany
Contact:

Re: New hardware revision?

Postby simon » Thu Oct 18, 2012 12:38 pm

Lee,

great to see you here! Welcome! :)

lee wrote:Drop the floppy, SD card support would be more usefull.

This would definately give some more space and drop issues I had with the FDC circuit. I never looked at the specs for SD cards. What communication protocol do they use?

lee wrote:Replace the EPROM with FLASH.

That is another good idea. It has been very annoying to burn the Eprom every time when I made small changes to the boot ROM.

lee wrote:Interface the keyboard/mouse directly, not too hard to do.

As long as I can read whole characters without the need of bit-banging the protocol, I am fine with that.

lee wrote:ISA bus slots for all my classic ISA CPU cards so I finally have a home for things like this.

I like this idea. With these slots I would drop the "keyboard computer" idea and would go for a standard sized PCB. But a downside of slots should be mentioned: If we stay a small community of enthusiasts and everybody uses other cards, don't we end in different incompatible systems without the possibility to join our forces?

I should take a look into the 030's datasheet. I always considered it too hard to work with. With a bigger CPU we should use other RAM modules. Maybe PS/2 SIMMS instead of these old 30 pin SIMMS. Latter are getting hard to find anyway.

Well, the main reason for the 68008 was the simplified PCB layout. Only a half or quarter of data lines have to be routed. My prototype PCB is a two-layer design. A four-layer PCB would be much more expensive.

Simon


cron