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Project30 - IIsi NuBus adapter in SE/30 trials - take 3
Posted by: Trash80toHP_Mini on 2019-03-13 09:40:22
Found a tidbit relating to researching the pre-NuChip, discrete component NuBus setup of Macintosh II.1 as well. Might need the ROM upgrade for logic analysis on the board or for comparative testing?

Rev.B-MacII-ROM-upgrade.JPG

One last goodie, The Master/Slave bugaboo of the SE/30 might be addressed using YARC's 74ALS651 approach to decoding?

74ALS651-decoding.JPG

edit: NTC = NuBus Test Card example in the Designing Cards and Drivers series.
Posted by: Amnesiac on 2019-06-04 16:06:35
Anybody got a lead on Inside Macintosh Volume V that's listed as indispensable in the CERN paper?
I have my copy of Inside Macintosh Volume V

Chapters 23(Device Manager) & 24(Slot Manager) are the only ones that I can see that might be relevant. I also found a train ticket from '95 that was bookmarking a menu manager chapter 🙂

I also had a look at Volume VI and chapter 30 has an updated Slot Manager section.

Let me know if I can be of any help.

Anything but the simplest of hardware is beyond me but I used to write bits of s/w back in the day 🙂 and I still have my first 512 (upgraded to a KE) and an SE/30 along with IM vols I-VI

A.
Posted by: Trash80toHP_Mini on 2019-06-04 20:26:44
Thanks, couldn't find it online so I ordered up both IV and V from abebooks.com. Read a bit of it, but have been obsessing about other things of late. Interesting what you find, someone's homework was still in a book on Logic Design that arrived last week.

Welcome aboard, love that username! :lol:

Posted by: Amnesiac on 2019-06-10 12:25:02
Thanks, couldn't find it online so I ordered up both IV and V from abebooks.com. Read a bit of it, but have been obsessing about other things of late. Interesting what you find, someone's homework was still in a book on Logic Design that arrived last week.

Welcome aboard, love that username! :lol:
If you want I can scan the slot manager section in Vol VI and if I could remember why I chose the username I'd tell ya! 🙂

Glad to be aboard... just plucking up the courage to re-cap my SE/30 at the moment... it needs to be done... I have the components... I can solder...  but I need to find some SMD caps to practice removing before I work on the SE/30 logic board!

A.
Posted by: Trash80toHP_Mini on 2020-01-15 08:16:28
View attachment 31065
Posted by: TPope on 2021-09-04 14:57:55
Do you still need plus of the ExpanSe/30? TPOPE
Posted by: Trash80toHP_Mini on 2021-09-04 18:18:28
That might be ideal . . . but . . .

Thanks much for keeping me on this train of thought for so long in PM and now again here. I have come up with a couple of thoughts with the project simmering on back-burner thanks to you.

#1 We have examples of a very simple, single PAL (+whatever?) NuBus adapter for the IIsi from the folks at Radius in hand which "just works" in the SE/30, albeit at only 8MHz. In this most simple of implementations, the PAL halves the 20MHz clock of the IIsi in order to produce the 10MHz clock required by NuBus.

#2 What I've been thinking is that someone with the chops to take a look at the timing mechanisms of NuBus would be the key to this predicament.

#3 The first release Macintosh II's NuBus (pre-NuChip) discrete component implementation is well documented. There are ample examples of that board available for analysis. What needs be done would be to de-couple the 20MHz to 10MHz clocking loop from the PAL of the Radius adapter to align it with the 16MHz clock of the SE/30 in the same (or similar) manner as was accomplished in the first rev. of the 16MHz Macintosh II.

Head's not clear ATM, so the above is a give or take kinda screed and I'll be away from my library for another week at best. Maybe @Bolle or @joethezombie can chime in with more info in the meantime on the Radius adapter? Likely with far more more technical observations than I can manage. I'm more an idea kinda guy, not a technically competent type of hacker in this day and age. I'm sure someone could implement the NuBus adaptation in CPLD/whatever should they wish to take a crack at it.
Posted by: johnsn on 2022-11-13 22:27:19
Hi, I messed with trying to get a Nubus adaptor to work in a SE/30 about 15 years ago.
I didn't do much, just plug a Nubus adaptor into a SE/30, You know rth results.
But I did get this.
Posted by: johnsn on 2022-11-13 22:28:33
I didn't get the board that goes in the SE/30.
Posted by: olePigeon on 2022-11-18 10:16:05
@johnsn Wow, that's cool. I've seen more Second Wave boxes this month than I have in my entire life. Would be cool to get one and fiddle with it. Hope you find the adapter. Might be rarer than the box since it was likely thrown out with the computer. 🙁
Posted by: johnsn on 2022-11-18 17:55:56
I have a Nubus adaptor. If I can find🙁 it.
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