GALSPanic - New X68000 RAM board

[PsychoLavos]

Sorry all, I have been away from the forums for a while. I still have remaining stock and sent out messages to those who wrote to me before.

If you did not hear from me, I am out of boards and will not be producing more. This is due to 3x price jump on the SRAM chip prices.

@PsychoLavos, your BOM is not correct on the SRAM chip area. You have 3.3v modules, and those will not be happy to work on a 5v system that is X68000. Mind you, it might work, but might also damage your precious system due to excessive current draw on bus pins. You will also have to program the GAL chip with JED files I published on github.

I do have around 8 blank PCBs of the v2 version to sell, so feel free to contact me for those.

Since I've already bought everything & I've yet to get the SRAM Chips from AliExpress, could you please link me to where I can get the correct SRAM Chips? As much as I don't want to sink more money than I have to into getting my X68000 up & running, I also don't want to damage it. So I'm considering paying the price on the SRAM Chips.

[stas2k]

The ones I sold had CY62167G-45ZXI installed from Digikey, and the prices went crazy there.

[stas2k]

I have found a source for SRAM and will be producing more boards in near future, so stay tuned.

Might have to adjust prices after I source the GALs as well. Seems prices went up for every part under the sun.

[PsychoLavos]

I have found a source for SRAM and will be producing more boards in near future, so stay tuned.

Might have to adjust prices after I source the GALs as well. Seems prices went up for every part under the sun.

If you are able to get a hold of new SRAM chips, is there anyway I could buy 4 Chips off of you? The Chips from Aliexpress arrived this week at my friend's house & I'm planning on refunding them if I can.

[PsychoLavos]

Sorry all, I have been away from the forums for a while. I still have remaining stock and sent out messages to those who wrote to me before.

If you did not hear from me, I am out of boards and will not be producing more. This is due to 3x price jump on the SRAM chip prices.

@PsychoLavos, your BOM is not correct on the SRAM chip area. You have 3.3v modules, and those will not be happy to work on a 5v system that is X68000. Mind you, it might work, but might also damage your precious system due to excessive current draw on bus pins. You will also have to program the GAL chip with JED files I published on github.

I do have around 8 blank PCBs of the v2 version to sell, so feel free to contact me for those.

I just realized something. Although I might be wrong, It wouldn't hurt to ask. I bought my PCB from eBay. The eBay listing says the board is V1.2. Would those parts work with a V1.2 revision board? I know you said I have the wrong chips, but I would like to make sure before I try & get a refund on those chips.

This is the eBay Listing where I got the PCB from. https://www.ebay.com/itm/234079296599

[Necron]

I have found a source for SRAM and will be producing more boards in near future, so stay tuned.

Might have to adjust prices after I source the GALs as well. Seems prices went up for every part under the sun.

Hi stas2k, sent you a PM requesting a GALSPanic card .

[stas2k]

Would those parts work with a V1.2 revision board?

All boards use the same SRAM chips. Only difference is in the package of the GALs.

If you are able to get a hold of new SRAM chips, is there anyway I could buy 4 Chips off of you? The Chips from Aliexpress arrived this week at my friend's house & I'm planning on refunding them if I can.

Nope, I will only sell built and tested boards not to go down support rabbit hole. I recommend googling around and trying to source your own. I do not recommend you try to build your own board unless you have significant experience in soldering small pitch SMD parts.

[PsychoLavos]

Would those parts work with a V1.2 revision board?

All boards use the same SRAM chips. Only difference is in the package of the GALs.

If you are able to get a hold of new SRAM chips, is there anyway I could buy 4 Chips off of you? The Chips from Aliexpress arrived this week at my friend's house & I'm planning on refunding them if I can.

Nope, I will only sell built and tested boards not to go down support rabbit hole. I recommend googling around and trying to source your own. I do not recommend you try to build your own board unless you have significant experience in soldering small pitch SMD parts.

My Friend is building it for me. He has more experience with soldering SMD components than I do. He's confident that he won't mess it up & he if does, he can fix it. My Friend nor I am asking for support if he messes up. I'm just asking if I could get chips from you, or if you could PM me the supplier you've found so I can get the chips on my own.

[stas2k]

I'm just asking if I could get chips from you, or if you could PM me the supplier you've found

Just search for the chip on aliexpress ot utsource. Me putting the board on MIT license does not imply I will provide support or help people build their own boards. Cannot recommend any suppliers as I still haven't got or tested any chips yet.

[stas2k]

Hello again! I will have a fresh batch of new boards built up this weekend. Feel free to PM for orders, and sorry about the price increase.

SRAMs became super hard to find, and Mouser jacked up GAL prices as well.

[SiQux]

Hello again! I will have a fresh batch of new boards built up this weekend. Feel free to PM for orders, and sorry about the price increase.

SRAMs became super hard to find, and Mouser jacked up GAL prices as well.

PM sent

[letchuck]

PM sent too

[TechnicalT]

Hey stas2k, what are prices like right now and do you still have any left? If I'm not mistaken, the github says the newest versions will work with 1mb stock systems right?

[letchuck]

So, stas2k logged 2 times since I wrote him in PM that I'm interested into buying one but I newer got an answer. I assume then that he doesn't botter to sell them anymore. Does anybody have a clue for another memory upgrade that one cane actually buy?

[nassekova]

I'm interested in one of these too if there are any more left?

[TechnicalT]

So, stas2k logged 2 times since I wrote him in PM that I'm interested into buying one but I newer got an answer. I assume then that he doesn't botter to sell them anymore. Does anybody have a clue for another memory upgrade that one cane actually buy?

Same here, no response at all. A true shame. I'd like to be able to play on my X68K that has no memory or find another feasible option.

[ymos16]

It is hard to find some of these chips. I was able to find most on DigiKey but the others like the exact GAL used, I'm waiting on from AliExpress and it's like a lottery to hope you get the right stuff.
If all goes well I'll report back here in a couple of weeks and hopefully help one of you build your own.

[ymos16]

So the rest of my ic's came in. Built, installed & confirmed working in my 2mb ACEHD = 10mb of Ram and able to play everything 😅 Big THANK YOU to the OP for making this Available. My first GitHub project and learned some things along the way.

V1.2 board (easily found online) Gal and SRAM from AliExpress (legit) and the rest from Digikey. Total Parts Cost give or take $40 USD

The only major curve ball was having to buy a Xgecu T48 Programmer because my old TL866 doesn't support the Gal's. Cost $60 USD

Grand total with Programmer about $107 USD (Building the latest version may be cheaper in parts and have better availability but I haven't looked into that yet)

I understand building one of these ain't for everyone and hopefully these parts become more readily available so the time & cost can justify shops/sellers to restock them again. Feel free to message me if you need some help. Peace.

[HIggy]

That looks great work @ymos16 the soldering on the Ram chips looks very fine!

I am still rocking 1mb hopefully will have a 1mb upgrade on its way. At the moment it is not worth using SASI as I only have about 400K free after booting an HD image!

[aotta]

@stas2k any news about classic 1mb machine supporting? all versions on github seems WIP about it

[ymos16]

That looks great work @ymos16 the soldering on the Ram chips looks very fine!

I am still rocking 1mb hopefully will have a 1mb upgrade on its way. At the moment it is not worth using SASI as I only have about 400K free after booting an HD image!

Thank You. A fine soldering iron tip and some good flux can work wonders. 😀

Yes, A min of 2mb is essential for these systems. I didn't even bother using mine until I got that situated and just focused on having it working %100 in the meantime.

[3rdman01]

Hello all. I'm going to try my hand at building a V2 version for myself...In fact, I have the PCBs and SRAM on order already. I am unclear though on the GAL chip and what is compatible. Can someone with the V2 model help me out? Thank you!

[ymos16]

The GAL for the V2 is a (ATF22V10C-10XU) I THINK I read in this thread or the GitHub issues that a different speed may not be a problem?, so if you can't find the 10XU maybe try to find something a bit faster or slower? by comparing the data sheets.

[aotta]

I've ordered the pcb v2 (with some variations, since i'll use a 24 dip gal that i'm able to program with my tl866) and the SRAMS, in the meanwhile i'm working on the GAL equations to use it with my 1mb classic X68000:
i'm not an expert in X68000 memory mapping nor in expansions' bus, so i ask to @stas2k or others experts if this are right for an 8mb expansion with 1mb only on board:

; SRAM Chip Enables
; Each chip holds 2MB of data. Address only valid on /NAS
; Lines are activated at these bus addresses:
CEM1    = NMSK * /A23 * /A22 * /A21 *  A20 * /NAS ;0x100000-0x1fffff
CEM2    = MS4  * /A23 * /A22 *  A21 *        /NAS ;0x200000-0x3fffff
CEM3    = MS6  * /A23 *  A22 * /A21 *        /NAS ;0x400000-0x5fffff
CEM4    = MS8  * /A23 *  A22 *  A21 *        /NAS ;0x600000-0x7fffff
CEM5    = MS10 *  A23 * /A22 * /A21 *        /NAS ;0x800000-0x9fffff


; DTACK
; Ground the line as soon as we have a valid address
/NDTACK = NMSK * /A23 * /A22 * /A21 *  A20 * /NAS
        + MS4  * /A23 * /A22 *  A21 * /NAS
        + MS6  * /A23 *  A22 * /A21 * /NAS
        + MS8  * /A23 *  A22 *  A21 * /NAS
        + MS10 *  A23 * /A22 * /A21 * /NAS


I missed something? any hints will be appreciated, thank you!

[mikewolak]

That looks right, coincidently I am working on the same project only with a v1.2 board. I'll be testing within a week or so depending on when my SRAM arrives from China, I'll let you know how it goes -

Mike

[mikewolak]

On second thought, regarding:

CEM5    = MS10 *  A23 * /A22 * /A21 *        /NAS ;0x800000-0x9fffff

Did you modify the board to have a 5th chip enable along with an extra SRAM? Everything else looks OK besides that line and  MS10 *  A23 * /A22 * /A21 * /NAS . If you removed those lines you would end up having 7MB of ram, with 1/2 of the 1st SRAM unused which I believe is your only option if you didn't modify the original schematic.

[aotta]

On second thought, regarding:

CEM5    = MS10 *  A23 * /A22 * /A21 *        /NAS ;0x800000-0x9fffff

Did you modify the board to have a 5th chip enable along with an extra SRAM? Everything else looks OK besides that line and  MS10 *  A23 * /A22 * /A21 * /NAS . If you removed those lines you would end up having 7MB of ram, with 1/2 of the 1st SRAM unused which I believe is your only option if you didn't modify the original schematic.

MS10 jumper is set on v.2 boards, to enable the 9-10 mb chips. I recycled it for the 7-8 banks for my 1mb version, as for others four banks (all in a "-2mb" logic compared to original).
Or i missed something?

I'm waiting for pcb and rams too, thank you mikewolak for sharing your progress!

[mikewolak]

Ok, in that case you should be good. Since you used a dip PAL in your design I say just give it a try and see what happens using mtest.x or some other memory checker after setting switch.x to the proper memory configuration. When I test I'm only going to solder the first 2MB chip to ensure the masking logic is valid.

[aotta]

Ok, in that case you should be good. Since you used a dip PAL in your design I say just give it a try and see what happens using mtest.x or some other memory checker after setting switch.x to the proper memory configuration. When I test I'm only going to solder the first 2MB chip to ensure the masking logic is valid.

Thanks, i've already planned an "incremental" filling for the SRams modules, since soldering them is what i'm more afraid of!