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JetPack for SE/30
Posted by: IlikeTech on 2018-03-05 19:37:46
I just had an idea. 

If someone can get the IIsi's NuBus adapter working in the SE/30, you could build a thing that goes on the back and holds the adapter as well as a Radius Rocket.  That would be one blisteringly fast SE/30.

Also, you could call it a JetPack for added awesomeness.

Posted by: BadGoldEagle on 2018-03-06 04:09:12
... or build something like an eGPU case to install your rocket externally.

I’d be down for that!

Posted by: IlikeTech on 2018-03-06 05:33:01
Now we just need someone to make the NuBus adapter work in the SE/30.  What ever happened to that effort?

Posted by: IlikeTech on 2018-03-06 06:44:31
I was thinking about the external idea, but that many wires would be annoying to run.

Posted by: Trash80toHP_Mini on 2018-03-06 09:40:26
The Expanse30 NuBus expansion box for SE/30 used a single cable. Pretty sure it was incompatible with the Rocket and it's way too big for a JetPack to look right anyway. Now NuBus-IN-SE/30  .  .  .

Project30-Testbed-02-1p.jpg

.  .  .  would be an entirely different story. 😛h34r:

Posted by: IlikeTech on 2018-03-06 09:48:54
Yes, something like an external dGPU box would probably be easiest.  I want a Rocket/30!

Posted by: Trash80toHP_Mini on 2018-03-06 09:55:14
IIsi/Rocket is faster than any possible SE/30 configuration. 😛

Posted by: epooch on 2018-03-06 09:59:44
The SE/30's 16MHz bus speed is not right for running 10MHz  NuBus. That's why the 20 MHz IIsi can do NuBus with so little hardware. You would probably need to accelerate the SE/30 to 20 MHz, and lose all of its onboard capabilities (including video and SCSI), or have a whole lot of hardware doing timing and caching. Basically another whole computer running NuBus. Maybe some card that are not timing dependent would work, but I can't think of one that wouldn't at least need a crystal change. Then your fast accelerator is running 25% slower, at best. 

Posted by: Trash80toHP_Mini on 2018-03-06 10:10:16
NuBus is independent of the processor bus clock. NuBus runs fine at 16MHz, it was introduced in the Macintosh II at that clock. The Rocket runs in IIx/IIcx and even the Mac II with FDHD ROM and PMMU upgrades to bring it up to near IIx spec.

All NuBus requires is the Controller and MUX setup on the processor bus, just three ASICs in the IIsi and anything later.

Interesting side note: discrete PMMU in the Mac II is the full Monty, the on die PMMU of the 68030 is a less capable, bargain basement subset of the 68851.

Posted by: epooch on 2018-03-06 11:28:43
NuBus Runs on a 10MHz clock, even on the II. The discussion was about a IIsi NuBus adapter. The Mac II has 4 state machines to keep the system synced up with Nubus. Maybe they are all incorporated into the IIsi NuBus adapter, but I don't see why they would be.

Posted by: Trash80toHP_Mini on 2018-03-06 11:50:04
Vanilla NuBus always runs on a 10MHz clock, it's processor independent. Don't remember that changing for NuBus90. Dunno about state machine involvement, just how the  hardware for NuBus is set up. It's "Controller" + "Transceiver/MUX." In the Mac II of 1987, there are a lot of discrete components involved, later implementations were done in Apple's ASICs that paralleled TI's integrated Controller/2 Transceiver chipset.

Project 30 is all about the IIsi Adapter. Check out the great new info just posted by nickpunt:

View attachment 21952

Posted by: epooch on 2018-03-06 12:41:55
Hmm. You just said 

NuBus runs fine at 16MHz, it was introduced in the Macintosh II at that clock.
which made me think we were on very different pages.

Anyway, good luck!

Posted by: Trash80toHP_Mini on 2018-03-06 12:50:09
OOPSIE! That was equivocal, should have said "NuBus expanhsion interface or chipset."

I'm usually on the other side of any given page. [😉]

Posted by: techknight on 2018-03-09 19:06:04
WTH is a radius rocket? 

Posted by: IlikeTech on 2018-03-09 20:19:57
It is an awesome NuBus 040 accellerator/secondary mac card.

Posted by: Trash80toHP_Mini on 2018-03-09 20:24:46
Funny you should ask, omidimo just scanned the manual! https://archive.org/details/RadiusRocketUsersManual

View attachment 21845

Posted by: omidimo on 2018-03-09 22:38:18
I won't take credit of scanning that, but I did upload it to Archive.org to make it easer to read up on it. BUT I will be scanning the RocketShare manual as that is not online. 

@techknight If you wanna learn more tech stats here you go:






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