SuperIIsiHack™ AKA SE/30's BANE . . .

[Trash80toHP_Mini]

I just realized that I don't really have a thread dedicated to this ongoing project, so, in no particular order:

SuperIIsiHack™ related threads:

IIsiColorPivotII_PDS_Card_HackProject™

UNDERClocking a Video Card??????

IIsi PSU: Catastrophic Failure! = 8-o

Switching Mac PSU's @$$tBits + ATX = ????? added 3.3.12

Clean/Prep depopulated board for repopulating?

Compatible solder type for thru-hole . . .

IIfx ROM SIMM in a IIsi . . .

TWO SLOT IIsi Nubus Card hack . . .

IIsiSuperMacPDSadapterRAMhack™

MicroQuadra "Evil Memory Hack" Redux

SuperIIsiHack™ related threads (not mine):

Clocking the IIsi by bibilit

note: I've been working on a compilation of the various idiocies I've undertaken, so I cribbed this list from my War Room scratch pad.

Hack Proposal:

So much arrention has been lavished upon the SE/30 (I lost mine down the storage room whirlpool) for so many years, by so many hackers that I thought I'd buck the trend . . .

. . . if you can imagine such a thing! [] ]'>

I decided it's time to pay very close attention to the SE/30 and IIci's bastardized, little-loved child. The IIsi has almost every "feature" I abhor in the MacWorld, so I got one off eBay! [] ]'> The IIsi is Physically Challenged, having far less apparent room/capability for expansion than either parent. I was an intentionally Intellectually Challenged (RAM Bus well and truly Hobbled) Mid-Market-Model with the obligatory level of the Middle-Child' Syndrome, being ignored by Apple and Hacker alike.

Not to forget that is was an intentionally lamed by the provision of an abysmally underpowered PSU to make it incompatible with the Radius Rocket!

I also decided my SuperIIsiHack™ should Kick the @$$ of any SE/30 ever hacked and give the much vaunted Quadra 840AV a run for the money! [}] ]'>

Specs:

NuBus Treachery:

Minimum Config:

Radius Rocket 33

__Lots of RAM installed on its local bus

__Fast SCSI II DaughterCard on that same local bus/PDS

__Radius Studio Array (Fast SCSI II RAID connected to the PDS SCSI II Daughtercard)

Maximum Hacked Config:

__DuoDock's Gemini Card Hacked onto IIsi NuBus Connection yielding Second NuBus Slot

____LittleRedRadiusPixelRocket™ in lower slot. for NuBus Block Transfer Graphics

Sub-Basement PDS Card Hack:

_____Minimum Config:

________10baseT EtherNet Card

________Radius Color Pivot II/IIsi Video Card (so there will be no Vampire Video detected on startup to mung up the performance of the baseline IIsi/Radius I/O device.

__Maximum Config:

________10baseT EtherNet Card

________TWO Radius Color Pivot II/IIsi Video Cards for a possible THREE Monitor Setup

______________This could possibly trump even the IIci's and 840AV's capability when they're paired with the second NuBus Slot/VidCard Hack

Under the Hood:

__Big V-8 Hemi ATX Power Railed goodness!

__a veritable vortex of cooling budget goodness!

. . . and a PseudoSlot ID ROMhack to bind them! }

mode>

Since the Rocket 33 will be blazing as an Accelerator under a lean, mean, tuned up 7.0.1, any Accelerated SE/30, almost any IIci Config and possibly even the 840AV will be left in the dust . . .

. . . and conspicuously missing their doors! :approve:

. . . or so the plan goes! :

 

[Mk.558]

It could give the SE/30 a run for it's money...

If the video card could fit in an SE/30:

Doesn't even fit in the chassis. Won't even go down far enough.

So we had to do this.

It's so tight, that the slot for a addon-chip rubs the edge of the ROM SIMM and nudges the metal shield at the back of the MOBO.

All that, for nothing.

Still, the IIsi has microphone in with stereo support BUT OH WAIT it records it in mono. Ooops. Still, with a JDW - style PowerSE/30, I think the IIsi can be chased pretty far. (Except in the color department.)

 

[Trash80toHP_Mini]

Thanks for going the extra mile for me in setting up that wonderful testing kluge, I really like it! Also thanks for posting your well documented results of the, first ever, Radius Color Pivot II/IIsi in an SE/30 test.

The fit shouldn't be an issue, I'll send you the modified riser card I hacked from the SuperMac IIsi RA PDS adapter along with the Serial Cable I forgot to pack for your 2300cTB. [] ]'>

I'm not even close to being discouraged about this combo yet!

Possible problems:

First: make sure there were are a pair of jumpers on that particular card. I swiped one for another test off one and that was probably the one.

From the pics, it looks like they're properly in place for one of the two available PseudoSlot Addresses, we can still try the other.

I'll check the Se/30's memory mapping to see if it's set to a IIsi only Slot ID and if the other Slot ID is recognized

You didn't happen to run SlotInfo from the Gauge series did you?

I forgot all about it and I wasn't thinking straight about using just the Monitors Control Panel for testing in the SE/30. There could be several software/driver issues contributing to the Monitors Control Panel being insufficient as a test tool. My bad! I think I'll copy these docs to the RCPII/IIsi thread for continuity there.

 

[Mk.558]

Too bad I already set it off in the mail back to you! :disapprove: That's okay because you'll have to get your IIsi in the first place!

EDIT: I'm curious -- are you building a SuperIIsiHack to kick the SE/30 off its throne? Because a IIci isn't that much more difficult and packs three NuBus slots (which is more than one PDS) AND can use something like this.

There. Instead of "nudging" the SE/30 off its pillar, BLOW IT OFF!

 

[Trash80toHP_Mini]

This project's not really so much about knocking the SE/30 off its throne so much as exploring/demonstrating more elegant methods of modifying and getting all the possible permutations of expansion cards to fit and play nicely together in either box. Most of the expansion card configurations documented on the gamba pages fall into what I'd describe as inelegant to down and straight through the kluge category, finally bottoming out at downright -F-U-G-L-Y-!

Demonstrating how to splay a set of PDS Cards straight across the underside of a IIsi MoBo translates directly into mounting a similar stack straight up from the SE/30's PDS.

A IIsi/SE/30 matchup seems to be about right to me. One is the most open example of the Compact Series, being the Bastardized offspring of the IIcx and the SE. The IIsi is the most constrained I/O expansion architecture of the Mac II series, being the bastardized/hobbled offspring of the SE/30 and the IIci.

In the hands of any hacker with a lick of sense, the IIsi would be the clear underdog in a matchup with the SE/30 . . .

. . . but I'm bat$#!^-crazy . . . so it looks like an entirely different proposition . . . challenge . . . from my point of view! }

 

[Trash80toHP_Mini]

The Carrera is an interesting card, but it suffers greatly in comparison to the "slower" Radius Rocket 33 running in Accelerator Mode.

The Rocket's RAM and Memory Controller are right there on the Accelerator - the Carrera needs to talk to System RAM across the PDS.

The SCSI II DaughterCard of the Rocket is on the same I/O bus as the Processor, Memory Controller and RAM, while the Carerra would need to do disk access across either the host's SCSI Chipset or a NuBus SCSI II Card, BOTH bottlenecked at the PDS level.

Removing bottlenecks has a great deal to do with overall system performance in the real world, MUCH more so than spurious claims re: speed increases due to raw processor clock rates! }

As for the IIci, that's not a fair matchup with the SE/30, whereas the underdog IIsi makes for a nice, cute lil' challeger of similar pedigree! [] ]'>

 

[IIfx]

So this is where that Rocket I sent you in that trade is going...cool use! Please, dont blow it up, that SCSI II booster isunobtainable.

If I understand correctly, the Rocket CPU will replace the IIsi 030? (NOT using RocketShare)

What are the performace pros of having the system CPU on a 20mhz Nubus bus? I am really curious now. I do understand that the RAM Bus on the Rocket is better than that on the IIsi motherboard.

Will the IIsi be transplanted into a new case, or will it sit on top of an auxiluary case?

So curious about this. Its interesting, cramming more than possible into something considered meh. Defeat Apple! Prove to the world how expandable the IIsi or any mac could be. :beige:

 

[Trash80toHP_Mini]

Yep! No worries 'mate, I've got my original Rocket 33/32MB for testing purposes. [] ]'>

The SCSI II Daughtercard won't be installed until everything is purring along nicely with room for the RAM above the IIsi's LOW PROFILE HDD.

If I understand correctly, the Rocket CPU will replace the IIsi 030? (NOT using RocketShare)

Correct, under Rocketware the '030 will be relegated to an I/O co-processor that won't even be hindered by the Vampire Video Subsystem's wait states.

This is akin to the two Apple II CPUs acting as I/O co-pros in your IIfx.

RocketWare eliminates the AppleTalk over NuBus overhead wth the host CPU as well. When the MoBo Proc isn't worth sharing, acceleration under Rocketware is the only way to go, given a single Rocket configuration, this is something I determined back in the day on my IIx.

What are the performance pros of having the system CPU on a 20mhz Nubus bus? I am really curious now. I do understand that the RAM Bus on the Rocket is better than that on the IIsi motherboard.

The 20MHz system clock on the IIsi makes it 20% faster (+ or - real world imposed limitations) for using any peripherals (Zip Drive, scanner, etc. on MoBo SCSI) than it was on my 16MHz IIx back in the day, or the SE/30 System/PDS clock. The RCPII/IIsi(s) ought to be noticeably zippier on the IIsi than on the SE/30 do to the higher PDS throughput as well.

Will the IIsi be transplanted into a new case, or will it sit on top of an auxiliary case?

Nope, that'd be cheating, comparisons to the SE/30 would be meaningless in that scenario, not that they're all that fair to begin with! }

This hack has to appear dead-stock from front, side & top views! The Rocket/SCSI II Daughtercard will be mounted in the standard IIsi NuBus Adapter. Unless, of course, I can get the DuoDock Gemini Card Hack to work. Then I'll need to finagle a different backplane cover plate to compensate for the shift straight away from the NuBus Adapter's hacked single slot, If all works out according to the vision, the Lower Slot will have a [color-red]RedRadiusPixelRocket™[/color] installed for 1024 x 768 x 24bit of NuBus Block Transfer 19' Display Goodness!

The PDS Slot is being shifted to the basement under the MoBo and the PDS Card(s) will be "stacked" sideways as compared to the SE/30.

The only sticky point will be breaking the IIsi's lamed PseudoSlot limitation of three available addresses.

So curious about this. Its interesting, cramming more than possible into something considered meh. Defeat Apple! Prove to the world how expandable the IIsi or any mac could be. :beige:

That's the Plan of Battle, the side benefit is to demonstrate a more elegant way to stack the '030 PDS Cards than anything documented on gamba. :approve:

side note: I just got my Output Enablers IIfx OverClocking kit in the mail today! [] ]'>

 

[Trash80toHP_Mini]

It could give the SE/30 a run for it's money...
If the video card could fit in an SE/30:

If the RCPII/IIsi were mounted atop the SuperMac Right angle adapter, would its length, or protruding bits, still present a problem?

I'm also going to be modifying an Asante 10baseT card for straight vertical or horizontal stackage. That'll be done along with another RCPII/IIsi/SuperMac RA Adapter pair. I just need to build a couple of cables to send units out for FULL BORE testing inside the SE/30 this time! [] ]'>

 

[bbraun]

I really honestly don't understand what is going on other than there are an awful lot of threads involving IIsi and pseudo-slots and wanting more. And I was doing a bit of reading in the Guide to the Macintosh Family Hardware and Designing Cards and Drivers for the Macintosh Family that may or may not be relevant to the idea of a IIsi and pseudo-slots and this seemed like as good a place as any to talk about it, because there's still a lot I don't understand about what I was reading.

AFAIK, it should be reasonably (as these things go) straightforward to get 3 nubus slots out of an 030 PDS slot, since as you've pointed out, 3 pseudo-slots. The 030 PDS has 3 interrupt lines, one for each pseudo-slot, so all is well. There's no interrupt lines to go beyond 3, and you can't really share any of the existing interrupt lines because those get OR'd together to generate a SLOTIRQ signal and toggle bits on VIA2 which indicate which pseudo-slot generated the interrupt, which in turn is used to determine which interrupt handler should be run. So, assuming >3 pseudo-slots "work", there's no interrupt for them. Do you have an interruptless nubus card in mind to use with such a slot? Looking over the Nubus documentation, I'm not entirely clear how interrupts work with bus master cards. It looks like the /NMRQ is used as an interrupt for non-master cards, or at least cards currently operating in non-master mode. Is it possible to implement nubus (as implemented on Macintosh II computers, since Designing Cards and Drivers specifically mentions other ways of generating interrupts according to the nubus spec, but only dedicated /NMRQ lines are supported by the Macintosh II family) without any interrupt hardware at all?

Now if you wanted the nubus slots and a non-pseudo-slot 030 PDS card that used the 030 PDS reserved memory area and didn't use anything else, that seems feasible...

When the Slot Manager runs from ROM, it iterates over the nubus decl rom address locations looking for a valid decl rom, and parsing it, as best I can gather. I haven't seen anything specifically indicating the SE/30 or IIsi ROMs do or don't iterate over the addresses for slots C and D (E is taken by the video "card" in the SE/30 at least). In fact, it's likely they do iterate over those "blank" address ranges since the SE/30's video card is a pseudo-card complete with declrom that should be parsed by the Slot Manager like everything else.

So, I guess my questions are:

Does it make sense to have a nubus card with no way to interrupt the host processor? Or do you have a solution to the lack of interrupts problem?

In the quest for additional pseudo-slots, do you have any indication they aren't being probed?

I guess an 030 PDS to Nubus with the Nubus ID1-ID3 lines set to C or D and /NMRQ not connected would be a test?

Anyway, I hope that makes some amount of sense, I'm getting blurry eyed reading these books.

 

[Trash80toHP_Mini]

Welcome to the world of blurry ancient Mac texts! [] ]'> Thanks for the heads up on the three slot interrupt limit, this is going to take more than just a little bit of crossed eyes time! :

I'm not worried about more than two NuBus Cards being addressed, as only two will fit inside the IIsi Case and there are only two slots available on the Gemini Card (upside down RA Riser from the DuoDock) that'll be mangled in this Multi-Slot Hack attempt. (although the NuBus Slot section of ANY Mac MoBo could be grafted onto any NuBus Adapter or a DuoDock LoBo.

Relevant observations:

I "know" there must be a way to generate additional(?) interrupts for NuBus PseudoSlots from a single(?) address/interrupt, because that's how the Expanse NuBus Breakout Boxes worked, IIRC.

Because there was an SE/30 Expanse NuBus Breakout Box, I "know" that the missing "NuBus" signal on the SE/30's PDS present on the IIsi' PDS "must be" possible to generate.

As I read the Mac II Architecture, the Slot Manager "probably" doesn't poll the NuBus for DeclROM PseudoSlot addresses mapping information directly. This appears more than likely to be done by the CPU first polling for the NuBus Chipset in order to establish the "NuBus Present" state. After that is established, the CPU likely has the NuBus Chipset report the DeclROM Info and the NuBus Slot Address/Interrupt location from what I was assuming to be digital glue identifying each particular NuBus Connector where any particular DeclROM happens to be located. From your report, this identifier may be as simple as the NuBus Chipset "knowing" the physical slot location by the "interrupt line" over which the DeclROM is "reported."

You "probably" won't find anything about such goings-on in the PDS documentation for the /030 PDS from the IIsi/SE/30 specific TechNotes, Dunno, that one's a WAG more than an observation.

Questions:

???????????????????????????????????

< brain blur >

???????????????????????????????????

< returns with first cup of coffee in hand >

Could the IIsi PDS "NuBus" signal be the /NMRQ line?

< makes note that we need an animated, old school/non-Mac, emoticon that crosses its eyes, tilts its head while lowering one eyebrow and then "crashes" >

Back to this specific hack's requirements:

The stock NuBus Adapter's Slot will be taken up by the Radius Rocket acting as the IIsi's CPU in its accelerator mode when the IIsi reboots after loading the RocketWare Driver during startup.

I ASSuME that the Rocket will be in Bus Master Mode as it communicates directly with any other NuBus Cards installed leaving the host's CPU and NuBus ChipSet in the dust as its I/O co-processor.

The NuBus Card I intend to use with the Radius Rocket 33 is the Radius 24X (ROM 2.0) which I ASSuME will be running in slave mode as it communicates with the Radius Rocket NuBus Master via NuBus Block Transfer.

New working theory/hypothesis:

Since the RocketMac Launches after the host Mac performs seppuku upon loading the RocketWare Driver . . . hrmmm . . .

. . . the Host Mac's ROM is Copied into memory on board the the Rocket . . . (yet another SE/30/Accelerator combo bottleneck bites the dust! [] ]'> )

. . . it must re-poll the NuBus for DeclROMs/Addresses for Cards awaiting enslavement . . .

. . . the Rocket MAY not really care which Mac in which it is installed for the purposes of PseudoSlot Addressing . . .

< more interesting images cascade from long term memory, overloading . . . xx( . . . reboot . . . >

It has been a VERY long time since I studied the workings of my original, brand spanking new, PRE-Quadra Radius Rocket 33, so take everything I've tried to communicate above with a very large block of salt.

My brain hurts . . .

 

[Trash80toHP_Mini]

I just realized that I can test for the NuBus Present State change on my IIsi/NuBus Adapter Card with TechTool!

< trots off to assemble related TechnoCrud on the workbench >

 

[bbraun]

I realized as I thought about this, I muddled up pseudo-slot with nubus. Pseudo-slots behave like nubus from a software perspective (mapped to the same addresses and interrupts are handled the same way), but nubus shouldn't be involved since there's no nubus transport and no nubus arbitration.

Pseudo-slots have interrupts, as designated by the 3 irq lines on the 030 pds. I'm not entirely sure how nubus maps interrupts, I was just guessing that was handled by the non-master request line, since afaict, there's no designated interrupt pin on the nubus connector. Which makes sense, because...

There are 3 ways to generate interrupts from nubus according to designing cards & drivers:

1) card writes to a designated area of memory that will generate a page fault, and the OS knows that portion of memory that was accessed was generated by a nubus card, and handles the interrupt. Not supported by MacOS.

2) Shared non-master request line between cards, which generates a processor interrupt, and the interrupt handler polls individual cards to figure out which generated the interrupt. Not supported by MacOS (but more on this later) because there's no defined way to poll cards to see if they're the ones interrupted, so Slot Manager can't route the interrupt.

3) Dedicated non-master request line for each slot. This is how nubus is implemented on macs, and all the NMRQ lines get ORed together into one SLOTIRQ interrupt line that actually interrupts the processor. Additionally, they get sent to VIA2. When the processor is interrupted by the SLOTIRQ interrupt, the Slot Manager's interrupt handler gets run, it reads VIA2, determines which slot(s) interrupted, and runs the appropriate interrupt handler(s).

Now, I don't know anything about nubus expansion cards. I don't have one, never used one. But, if I were trying to solve this interrupt problem for an expander, I'd make the expander card keep track of which of the expanded slots generated the interrupt, OR those into my own NMRQ line, and then have my own software (installed via the declrom, preferably) register an interrupt handler as an interrupt router for the expanded slots, which would then query my card for which expanded slot really generated the interrupt, and then route the interrupt as appropriate. This means you do the shared NMRQ approach above, except you're doing the routing on behalf of the Slot Manager.

A hacky alternative might be to manually run wires from a 4th pseudoslot card to both the SLOTIRQ line and the appropriate pin on VIA2, since I'm pretty sure slots C and D pins on VIA2 are unused on the SE/30... That might avoid the need for a full blown expander. Maybe.

 

[Trash80toHP_Mini]

< does proposed NuBus Present State testing in NuBus/PDS Slots report/ TattleTech 2.8.1 >

Well . . . that was particularly inconclusive . . . but interesting . . .

____________________________________________________________________________________

Inconclusive Part:

TattleTech General Hardware report:

TattleTech appears to read the NuBus Present State from the presence of the Slot Manager, in this case:

_____+Slot Mgr Version = 2 (ROM Based)

TattleTech NuBus/PDS report:

_____Total Physical PDS Slots Present = 1

_____Total Physical NuBus Slots Present = 0

_____________________________________________________________________________________

Interesting Part:

The NuBus/PDS report's Physical Slots Present result remains the same in all three possible states tested:

1) Stock IIsi: no NuBus Adapter (Chipset?) installed

2) NuBus Adapter w/o NuBus Card

3) NuBus Adapter w/NuBus Card installed

Additional states come to mind:

4) RCPII/IIsi Card Installed

5) RCPII/IIsi and Asante MacCon 30/si Cards Installed

. . . No Change!

Did some more NuBus Adapter on PDS passthru and got strange results . . .

. . . it either hangs or it tries to boot and then dies in an incredibly gruesome (very loud/disturbing sound effects) manner! 8-o

Meanwhile, it's time to buzz and re-flow at least one of the solder connections on my SuperMac Straight Up adapter RA Adapter Card . . .

. . . apparently I borked it! :approve:

 

[bbraun]

Yeah, the Nubus/PDS report seems about right, since that's what is physically present (from a certain point of view...). I haven't seen anything obvious that would let me probe from software the presence of a slot, particularly if it is empty. I might just be missing something, my knowledge of the area is woefully incomplete. But, I've done a fair bit of reading on the subject and haven't come across anything obvious, so continuing on that line of thought, if there isn't a way to probe the presence of a PDS slot, only the presence of devices on the bus (which may be present through a PDS slot, we don't really have any way of knowing), then that one PDS slot/no nubus report is based on inferred information. Such as knowing you're on a IIsi and IIsi's have a single 030 PDS slot.

What I'd really be interested in is if you have an 030 PDS card that uses a pseudoslot, and you can configure it for slot C or D. Most should only be configurable for slot 9-B since at least on an SE/30, those are the only fully functional pseudo-slot IDs, since there are only interrupts for those slots. The Asante MacCon card should allow configuring in 9, A, B, and I think E (but SE/30's video uses E, not sure about IIsi). You might be able to do some hackery to get it into C or D... If you somehow managed to get something into slot C or D, without an interrupt line (we don't want it inadvertently using a different slot's interrupt line), it would be interesting to see if the decl rom is present and if any decl rom driver is loaded. Any such driver might not actually work since there's no interrupt line, but the presence of the decl rom and driver would indicate the slots are being mapped properly (I haven't seen any indication they aren't, but a real world check is good). If the driver's Open routine fails (possibly due to missing IRQ line, who knows), it may stay loaded in the unit table, but be unavailable to higher level software. If it stays loaded in the table, that's smoking gun evidence that the decl rom was found, parsed, and driver loaded.

Ever since my first shot at that memory disk driver, I've been working on and off on a tool to examine drivers present in the unit table. That tool would be useful for determining whether the driver. You can traverse the unit table with macsbug, but it's not pretty.

I also seem to recall some of the early developer cdroms from Apple had declrom utilities to aid in the development of cards. One of those might be helpful. The MESS guys also had a tool for dumping declroms, I haven't run it, but that might also be helpful.

 

[Trash80toHP_Mini]

I need to get TechTool onto the IIsi, but I haven't bothered yet as I need to configure a low profile SCSI HDD for running 7.0.1/Tune-Up so I can determine if Apple cheaped out on the PSU to make the Rocket incompatible or if they borked the NuBus adapter, on purpose, just to prevent the IIsi from being converted to blazing 33MHz Quadra status even before they released the Quadras. That's where my IIx/Rocket33 sat at the top of the CPU food chain, and then remained there until the 840av was released.

I need to do the "machine pin" hack onto the soldertail cones of the PDS and replace the RA PDS Connector on one of my RCPII/IIsi Cards to test NuBus w/subterranean PDS Video. If that works, the PassThru Slot will be hack to Right Angle/Straight Up status for adding the Asante NIC.

Testing was done with addresses:

$00 = Macintosh A Built In Video

$09 = NuBus Adapter Default

$0A = RCPII/IIsi, the only other available Slot ID is $9

$0B = Asante MacCon30si, the only other available Slot ID is $9

I tested EVERY POSSIBLE jumper config on both PDS Cards . . . makes sense, but it'd be nice if both, or either of them, could use all three available PseudoSlot IDs. :-/

 

[bbraun]

Yeah, I don't think any 030 PDS card is going to officially allow a slot C or D configuration with the jumpers. The jumper configuration should tell the card both what address range to respond to, and which IRQ line of the 030 PDS slot to use, and hopefully this is some GPIO pins read by an onboard controller, because that'll pretty much be doom. So, hacking the card(s) will be necessary to be able to configure it to use a different slot, in order to get more cards working.

One ray of hope is the MacCon+30iET64 supposedly supports being configured as slot E (according to the SE/30 minitower page), which won't work on an SE/30, but it seems the IIsi's video doesn't use slot E, so all would be good. So if you got that working in slot E, you'd have 4 pseudo-slots in use?

If your MacCon allows configuring as slot E, and it doesn't work, that might be worth further investigation to figure out why.

Reading the IIsi dev notes, it seems it had 4 IRQ lines on the 030 PDS, not the 3 I had initially thought on the SE/30. Presumably the 4th is the slot E's IRQ line, which is in use on the SE/30 but not on the IIsi. So, 4 pseudo-slots doesn't seem unobtainable on a IIsi. Does the 3rd edition of the Guide to ... Hardware cover the IIsi? If so, the VIA and 030 PDS chapter might have some insight.

 

[Trash80toHP_Mini]

I think GttMFH topped out at 2e and went TechNote.pdf only for the IIsi Rollout. :-/

ISTR there being some Printed Tech Material on the IIfx that's available as scanned pages somewhere on the web . . . or on one of my HDDs . . . or somewhere in my files . . .

. . . or not! )

edit: While googling for info on any newer version of GttMFH2e, I found an interesting site: the Internet Archive

I'm just about done downloading the next to last .pdf on page three of this grab-bag of cool retro computer offerings.

OOOOHHHH!!!!!!!!!!!!!!!!!!!!!!!! BABY! It's in there, but I really like my dog-eared old wood pulp based storage media version from back in the day a LOT better! [] ]'>

This version will be nice to have on HP_Mini's SSD though!

 

[zuiko21]

Wow! Thanks for the link!

I'd like to ask a couple of things about it:

1) If one already has the GttMFH2e, is there any need for the first edition?

2) Would the Macintosh Family Hardware Reference complement it in some way, or does it become superfluous?

Thanks a lot in advance!