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Daystar Universal PowerCache P33 in SE/30
- Thread starter K Trueno
- Start date
K Trueno
Well-known member
Just a random dude wanting that last 3-4 MIPS out of a 68030 machine along with someone that actually knows what's going on!
But yeah I think this is pretty big news for llsi Adaptor/TwinSpark/ProtoCache users. I mean there have been these types of builds described on Gamba's site that would have the same problem. Not everyday you discover something new 20 some years odd on, all thanks to @Bolle .
Don't have a pic, but, cheers!!
Bolle
Well-known member
Going to verify both, the SE/30 vs. IIsi adapter and P33 vs. SE/30 PowerCache thanks to @Udo.Keller who sent me some things to play with
View attachment 28421
Excellent!Going to verify both, the SE/30 vs. IIsi adapter and P33 vs. SE/30 PowerCache thanks to @Udo.Keller who sent me some things to play with
nickpunt
Well-known member
Be careful @Bolle, that does not look like a P33 card - no label in lower left corner. Yours looks like the regular non-universal powercache card (seen here), which I believe only works in the IIci. Not positive, but there might even be an electrical risk of plugging one of those + adapters into non-IIci machines.
For reference, here's what my P33 looks like.
EDIT: Looks like I'm wrong, see @omidimo's response below.
For reference, here's what my P33 looks like.
EDIT: Looks like I'm wrong, see @omidimo's response below.
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nickpunt
Well-known member
Interesting. I don't understand what changed to make the P33/P34 ones 'universal' then, if prior ones still worked with adapters. The TwinSpark states it can only work with P33 cards, but then again the TwinSpark is most likely a clone of DiiMo's IIsi adapter.
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omidimo
Well-known member
The P33 added support for a slew of later 68K machines:
l
Looking at this, the design was modernized with fewer chips but DayStar altered the location of the support spacer hole:
The spacer optimization is clear on this image:
I have both card versions, but I never tried either in my SE/30s... got the Diimo and a couple of Turbo 040s. }
l
Looking at this, the design was modernized with fewer chips but DayStar altered the location of the support spacer hole:
The spacer optimization is clear on this image:
I have both card versions, but I never tried either in my SE/30s... got the Diimo and a couple of Turbo 040s. }
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K Trueno
Well-known member
Summary: if you are using a TwinSpark with a Universal PowerCache, you are not getting full speed compared to the Socketed PowerCache. This is because the cache is not enabled even if it is turned on in the control panel. To enable the enabling of the cache, add a jumper between C11 and C13 on the cache slot of the TwinSpark.
This may also apply to the IIsi adaptor and DiimoCache adaptor but we don’t know for sure.
Bolle
Well-known member
It does. It also applies to the adapters I built so far. You will have to jumper the /CENABLE pin (C13 on the cache slot connector) to ground, otherwise the cache won’t get activated.
Bolle
Well-known member
So neither the GAL nor the 74ACT86 do anything on that SE/30 adapter if you use it in the SE/30...
The GAL code is the same as on the Daystar IIsi only adapter.
The input signals present at the GAL are the same as on the IIsi adapter, only a few output pins are routed to different places on the SE/30 connector.
Only signals that are important are on pins 17, 18 and 19.
/CFLUSH stays high all the time. Pin 18 (connected to C20 on the SE/30 cache connector) is high all the time as well.
/CENABLE stays low all the time.
The 74*86 outputs a high signal all the time as well because the two inputs 1 and 2 are receiving the same signal. CPUCLK and C16M are tied together on the SE/30 PDS slot.
It will only output something on the IIsi where CPUCLK is 20MHz and C16M is - guess what :tongue: - 16MHz. The signal coming out of there is then routed to /CFLUSH on the IIsi cache connector.
This means for a P33 -> SE/30 only adapter there isn't any GAL (or even any chip) needed at all. A 7486 to boost the clock signal if you use two PDS cards would be a good thing to do though as this constellation might cause problems otherwise.
If you wanted you could even wire up your P33 to the SE/30 PDS using a lot of jumper wires. No magic going on here at all.
The GAL code is the same as on the Daystar IIsi only adapter.
The input signals present at the GAL are the same as on the IIsi adapter, only a few output pins are routed to different places on the SE/30 connector.
Only signals that are important are on pins 17, 18 and 19.
/CFLUSH stays high all the time. Pin 18 (connected to C20 on the SE/30 cache connector) is high all the time as well.
/CENABLE stays low all the time.
The 74*86 outputs a high signal all the time as well because the two inputs 1 and 2 are receiving the same signal. CPUCLK and C16M are tied together on the SE/30 PDS slot.
It will only output something on the IIsi where CPUCLK is 20MHz and C16M is - guess what :tongue: - 16MHz. The signal coming out of there is then routed to /CFLUSH on the IIsi cache connector.
This means for a P33 -> SE/30 only adapter there isn't any GAL (or even any chip) needed at all. A 7486 to boost the clock signal if you use two PDS cards would be a good thing to do though as this constellation might cause problems otherwise.
If you wanted you could even wire up your P33 to the SE/30 PDS using a lot of jumper wires. No magic going on here at all.
ktkm
Well-known member
There are .1" pitch ribbon cables. I don't think I've ever seen a premade cable with a Euro-DIN connector on the end. I'm also pretty sure that the easily available ribbon cables don't go past 40 or 50 conductors. I looked into trying to bring the SE/30 CPU socket up with ribbon or flat flex cables some years ago.
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