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Author Topic: A1200+ Project New Motherboard Replacement  (Read 4651 times)


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Offline ErolTopic starter

A1200+ Project New Motherboard Replacement
« on: July 22, 2019, 07:25:39 PM »
not sure if this is already been posted, but check this out.

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Offline paul1981

Re: A1200+ Project New Motherboard Replacement
« Reply #1 on: July 23, 2019, 10:53:39 AM »
I like it! Impressive stuff.  8)

Offline Brian Hoskins

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Re: A1200+ Project New Motherboard Replacement
« Reply #2 on: July 25, 2019, 12:40:13 PM »
It's definitely impressive, and an interesting project.

Personally, if I were re-producing an A1200 board with some minor improvements, I would want to retain full backwards compatibility with the traditional A1200.  So that would mean retaining all the outgoing connectors (power, DTYPEs), retaining the PCMCIA, etc.  The only connector that I might consider ditching would be the standard video output, in which case I would look at replacing it with a more modern scan-doubled output.  Not sure if I'd go full modern with HDMI or stick with VGA for compatibility with older CRT monitors, I'd need to have a think about that.

I like the forward thinking for an RTG board development.  It would be even better if there could be auto-switching between this (for, say, Workbench) and the standard AMIGA modes (for games and legacy software etc) via a single graphics output.

I don't feel like I approve of the relocation of Gayle, Budgie and the DRAM to a daughter board.  I could be totally wrong here but my intuition tells me that this could end up being a source of trouble in the future in terms of worn connectors etc.  It's generally troublesome to have boards hanging off parent boards via connectors, as anyone who has used the trapdoor slot for accelerators will know - especially in towered A1200s.  The choice of connectors is good, it looks like these would tend to limit the movement of the daughterboard once plugged in.  Still, my intuition about trouble with this is not quite satisfied.
What is the main driver behind this decision? I guess there's an advantage to the relocation of these components that I am failing to consider.  If it's important to have these on a daughterboard I would probably look to have a mounting solution whereby the daughter board can be secured to the motherboard via screwed-in posts so that it's not flapping around and causing grief.

I know I'm feature-creeping here but some on board networking would be nice, especially since the PCMCIA slot has been removed.  I see that this has been considered via a terrible fire compatible SPI port but I don't have knowledge of how that would work in practice.

An upgrade from IDE to SATA would be good too, although possibly a non-trivial exercise and I guess many A1200 owners use a simple CF card solution which is quite well suited to IDE.

Anyway, I'll keep an eye on this to see how it develops.  I've got a couple of those new cases produced by A1200.net and some replacement keycaps on the way, this is the kind of thing that would be well suited to a revamped A1200 desktop build.

Offline outlawal2

Re: A1200+ Project New Motherboard Replacement
« Reply #3 on: July 25, 2019, 03:01:10 PM »
I love the fact that we are getting new boards for our beloved Amigas, 4000, 1200 and I think I saw a 3000 board out there as well..
This is awesome..

I, however would really like someone to provide COMPLETED boards at some point.  I have years of experience with multiple platforms, but I do not have the expertise to solder everything up on these boards so the projects are not currently attainable for me.  I am quite certain that I am not the only one that feels this way.

Any chance someone can look at producing completed boards based on these chip-less mainboards and sell them to folks like me that REALLY want a new Amiga.
I am working on a few ideas for new 3d printed cases and would love to make a case for a brand new 3000 board fully populated along with one of the new A3660 060 boards that I have seen on Ebay.  A new system with all new internals would be awesome stuff indeed.

Anyone out there want to take a stab at this?

Offline save2600

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Re: A1200+ Project New Motherboard Replacement
« Reply #4 on: July 25, 2019, 04:10:13 PM »
As always, neat project - but... totally agree with the notion that such projects should, could and need to be released as 'completed' at some point. At the very least, offer them up as full kits where all one has to do is solder everything up - and then you'd have something besides a wall decoration.

The Amiga community is replete with projects. Half finished, partially finished... most of the time, nothing but a bare board. In fact, I've lost count as to how many boards are available for the various models and systems. Lots of them available on eBay, with little to no description as to how to finish. Or with such language as "check the web" for details. So you spend countless hours trying to track down this and that, sometimes/most of the time, as you try to decipher foreign languages.

Only to get so far... when you realize that, duh! Something like an obsolete component or PAL chip (that doesn't really exist or can only be programmed by one guy that may or may not even be alive or offering their services at any given time) is all that's needed to finish whatever.

Can be frustrating!   ;D
« Last Edit: July 25, 2019, 06:55:14 PM by save2600 »

Offline paul1981

Re: A1200+ Project New Motherboard Replacement
« Reply #5 on: July 26, 2019, 12:01:15 PM »
I wonder if there's some legal reason they can't sell populated boards? Or it might be seen as risky. It really wouldn't surprise me at all being as though there are Commodore-Amiga branded / licensed chips going in there whether they be NOS or reclaimed.

Offline save2600

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Re: A1200+ Project New Motherboard Replacement
« Reply #6 on: July 26, 2019, 02:00:56 PM »
I was surprised when I finally landed a Phoenix board (original Australian) and found it did NOT include the necessary circuitry needed to take advantage of some of its best features. In this case, the missing circuitry comes in the form of PAL chips. You need a special PAL chip for multiple Kickstarts. Need a special PAL for the HD circuitry. Probably even for the co-processor socket, etc.

I get needing to populate a board with Agnus, Paula, Denise, Kickstart and CIA's. Hell, maybe even the SCSI controller chip and others which are relatively easy to source, but PAL chips? Seems to be the #1 thing holding up the new Rejuvenator boards also - those dreaded PAL's.  lol
« Last Edit: July 26, 2019, 02:44:18 PM by save2600 »

Offline NinjaCyborg

Re: A1200+ Project New Motherboard Replacement
« Reply #7 on: December 29, 2020, 11:06:07 PM »
Why do you need multiple kickstarts?