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Mac SE/30 w/Stratos TwinSpark adapter and DayStar PowerCache P33 32K cache enable issue
Posted by: jasa1063 on 2022-07-01 10:40:21 I just picked up a Stratos TwinSpark adapter for use in my SE/30. I have a DayStar PowerCache P33 50MHz accelerator. It works fine in my Mac IIci. When installing it in the SE/30 with the Stratos TwinSpark adapter, the 32K cache will not enable. I am using version 2.2 of the PowerCentral software. The jumpers on the TwinSpark are set to default JP1 - 1 Off, 2 On, 3 On. The TwinSpark board is revision 2.0. The PowerCache is plugged into the cache slot on the TwinSpark. Anyone have any idea why this would be happening?
Posted by: Bolle on 2022-07-01 12:06:06 The TwinSpark isn’t made to support the PowerCache despite what Artmix advertises. It only really works with the DiiMO 030. You can get the cache on the P33 to work by soldering a jumper between ground and the /CENABLE pin (C13) on the cache connector.
Posted by: jasa1063 on 2022-07-01 12:28:28 The TwinSpark isn’t made to support the PowerCache despite what Artmix advertises. It only really works with the DiiMO 030. You can get the cache on the P33 to work by soldering a jumper between ground and the /CENABLE pin (C13) on the cache connector. View attachment 43281 Thanks for the information!
Posted by: bcschmidt on 2022-07-09 18:50:06 Same issue here. I have a 33mhz p33. Freezes instantly the second I enable cache.
Posted by: bcschmidt on 2022-07-09 18:50:57 I also soldered the jumper, makes no difference. Tried everything lol, 5v is spot on.
Posted by: compu_85 on 2022-07-18 10:03:32 The TwinSpark isn’t made to support the PowerCache despite what Artmix advertises. It only really works with the DiiMO 030... Hmm, I was just looking to buy one of these to use a DayStar PowerCache 50 mhz 030 accelerator. Are you saying this isn't a good plan? -J
Posted by: Bolle on 2022-07-18 13:38:12 Depends if you’re ready to install a bodge wire to get the cache to work on the P33 (or yet another bodged on resistor on top of that if you want to use the P31) There’s a few reports where even those two didn’t cut it and people could never get the cache to work. It’s on you if you want to take the risk of not having it work at 100% of the capable speed of the PowerCache. That said there’s more reports from people who have the cache working with the single bodge wire installed than people who couldn’t get it to work…
Posted by: compu_85 on 2022-07-19 14:59:26 Ok. I have the P33 cache cards. I'm fine with adding a bodge wire... if it works. Thanks for the advice! I also only manage to see your board listings a month or two after they've all sold 😵 -J
Posted by: compu_85 on 2022-07-28 15:04:19 I guess I got lucky 🙂
Posted by: compu_85 on 2022-07-29 07:14:03 Though, I don't see much of a difference turning the cache on / off. I wonder if the UI isn't able to detect the actual state of the cache?
Posted by: Bolle on 2022-07-29 08:35:43 You’ve got to run a benchmark to confirm it’s actually working. The Daystar Power demo is good for showing off the speed boost of using the cache.
Posted by: compu_85 on 2022-07-29 08:49:42 Right - I don't see a difference in Power Demo turning the cache on and off. I assume if things are working properly, a logic probe should show a change on the /CENABLE pin when toggling the cache on and off in the control panel? -J
Posted by: ymk on 2024-06-18 18:32:25 I'm having the same issue with a P33 clone and PowerCentral 2.2. No difference in benchmarks between cache on and off. /CENABLE is always high - control panel doesn't affect it. Grounding /CENABLE causes the control panel to crash on boot. Grounding /CENABLE without the control panel yields the same benchmarks.
Posted by: Bolle on 2024-06-18 23:31:40 The /CENABLE signal is an input to the PowerCache, it will not reflect the state of the control panel setting. Only the cache control logic on the IIci/IIsi will actually drive that signal, on all other adapters it will just be pulled low. To actually activate the cache the control panel also flips a bit in one of the registers at a specific address on the PowerCache. The control panel crashing actually indicates that it probably did activate the cache and something else went wrong. That’s happening with the adapters I sent along? I’ll have to check if there’s anything else preventing the cache to kick in.
Posted by: ymk on 2024-06-18 23:35:51 That’s happening with the adapters I sent along? I’ll have to check if there’s anything else preventing the cache to kick in. Yes, this is with your P33 and riser card. I'm not using the TwinSpark.
Posted by: mike_c on 2025-05-16 09:14:51 Depends if you’re ready to install a bodge wire to get the cache to work on the P33 (or yet another bodged on resistor on top of that if you want to use the P31) There’s a few reports where even those two didn’t cut it and people could never get the cache to work. It’s on you if you want to take the risk of not having it work at 100% of the capable speed of the PowerCache. That said there’s more reports from people who have the cache working with the single bodge wire installed than people who couldn’t get it to work… I know this is an old thread, but I wanted to report that performing the bodge wire mod on the TwinSpark does indeed enable the cache on the P33's. I did this with 2 different TwinSparks and 2 different PowerCache 50's and had 100% success.
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