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Posted Wed Nov 24, 2021 9:52 pm

I'm so glad the project came to fruition! I too jumped the gun with the boards (sorry :/) but here's mine in purple. <3

SOJ DRAM seems to be the way to go. Also made some adapters without needing to trim/overlap components and leads.

This now has to sit and wait until I finish my front RAM upgrade project (my A1000 is stock 256KB so I'm quite sure from the manual this can't work without it) and an adapter board to use an A500+ Agnus (as found on GitHub, but I need a version with SMT plug).

I'm already thinking about a custom CPLD/RGBToHDMI for the video expansion port to save on a redundant card edge adapter.

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New Orleans, LA, USA

Posted Thu Nov 25, 2021 7:11 am

That looks great! Can you share the SOJ adapter Gerbers with us?

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Posted Thu Nov 25, 2021 8:54 am

I thought that any motherboard RAM just went into Ranger memory.

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Seattle, WA, USA

Posted Thu Nov 25, 2021 8:55 am

@rlake That looks FANTASTIC! Prince would be so proud. :)

And I love your all-in-one RAM board. Greg Tibbs did something similar back in the day.
Happy Thanksgiving, all.

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Posted Thu Nov 25, 2021 2:07 pm

nonarkitten wrote:
Thu Nov 25, 2021 8:54 am
I thought that any motherboard RAM just went into Ranger memory.
I wasn't 100% from reading the documentation if it required 512KB base for some reason, so it's more than likely my misinterpretation of the jumper settings. It would make sense what with there being a Kickstart ROM! I will be ok with 2 1/4 MB, though I suppose that still depends on the software. :)

Happy to share the Gerbers. These are from the JLC/SEEED profile but if there's another preference I should be able to figure out how to export.

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Posted Fri Nov 26, 2021 11:14 pm

Aha! It's because there's no 256K option for J101/102. Possibly a custom GAL for U31 could "fix" that. There appears to be a spare pin but no idea if there's space internally.
If the screen comes up yellow, it means that the front panel RAM expansion is missing when the Kickstart ROM option is selected (This is only included for completeness. In Kickstart RAM (disk) mode, a missing front panel RAM would cause a robin’s egg blue screen). Check to make sure that it is well connected to the A1000 motherboard.
The Amiga custom chip registers, nominally located at DFFXXXH, actually mirror (or tile) all the way down to C00000H or the end of C00000H RAM. The Kickstart ROM, at best, behaves erratically when there is a section in CXXXXXH that is not decoded at all. Usually, the result is a yellow screen. This will happen if the 256K front panel expansion is missing. Since there are two memory possibilities—512K, and 1024K (1 Meg)—two of the combinations of jumpers J101 and J102 ensure that there are no undecoded areas to cause a “Yellow” screen error.

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