AE TW2340 (TW1340) Accelerators - Maximum RAM

[superjer2000]

I recently acquired an Applied Engineering TW2340 accelerator for the Macintosh Classic (40mhz 68EC030 with FPU and SIMM sockets).

Sales materials on the accelerator available here (https://www.savagetaylor.com/2022/06/07/68k-accelerators-fpus-and-other-cpus/) indicate it does NOT support Connectix Virtual (which makes sense as it as an EC030 lacking an MMU) but DOES support more than 4MB of RAM.

My card came with 16MB installed, however the control panel I can find (AE's Warp 030) shows there is only 4MB of physical RAM installed. The same sales materials seem to suggest that 4MB has to be installed on the host computer, which mine has.

Another post regarding a TW1340 card (essentially the same card but designed for the Mac SE) on AppleFritter seems to suggest that when the card was first introduced, it only supported 4MB but, after being contacted by AE, he sent his card back in for a modification and it supported 16MB. It doesn't seem like that support was through Virtual, but rather some other means, but it's hard to say for sure.

Does anybody have any experience with these cards and has been able to get more than 4MB to successfully recognize? I have considered trying to swap out the SIMMs for another set of 4x4MB SIMMs but I'd rather not to avoid busting SIMM sockets etc, especially given that I have found a couple other posts online where people haven't been able to break the 4MB barrier with their TW1340/2340 cards making me think it's the card, or the drivers, and not an issue with the currently installed SIMMs.

 

[superjer2000]

As an update, I tried the TW2340 in a different Mac Classic, and tried different 4x4MB SIMMs. Same issue, it only shows 4MB of RAM installed. It would be very interesting to read the manual for this card (TW1340 or TW2340) if anybody has a copy

 

[Realitystorm]

There are some accelerators with EC030 CPUs that could support 16MB if you swap out the CPU for the full version.

 

[superjer2000]

There are some accelerators with EC030 CPUs that could support 16MB if you swap out the CPU for the full version.

I am curious to know what would happen if I did replace the EC with a full 030. My gut is that I would then be able to use Connectix virtual to use disk based virtual memory but that the accelerator still wouldn’t see the any more physical memory, so I wouldn’t be much further ahead than I am now. The processor is soldered on and I don’t have an available 40mhz+ 030 to test it out so I may not pursue this. I think something has to change on the board for it to actually see the additional physical memory.

 

[ObeyDaleks]

Did you actually try Compact Virtual to see if it works? I have several of these early accelerators with onboard RAM and they all rely on Compact Virtual to unlock the full 16MB. Maybe AE used some of their magic to make it work with Compact Virtual despite it being a EC CPU?

 

[superjer2000]

Did you actually try Compact Virtual to see if it works? I have several of these early accelerators with onboard RAM and they all rely on Compact Virtual to unlock the full 16MB. Maybe AE used some of their magic to make it work with Compact Virtual despite it being a EC CPU?

I did. When opening the CDEV it it says no MMU or 68040 and it doesn’t load at boot (has an X through it)

 

[Realitystorm]

I was able to use compact virtual after I swapped the CPU on my Mobius board.

 

[Realitystorm]

For support for 16MB without the MMU it could be as a ramdisk?

 

[superjer2000]

I was able to use compact virtual after I swapped the CPU on my Mobius board.

For support for 16MB without the MMU it could be as a ramdisk?

Thanks for this - For clarity, when you say you could use Compact Virtual after swapping to a full 030, does that mean that:

a) You could then use Virtual to create a swap file on your hard disk to use (slow) virtual memory; or
b) Your accelerator began to report > 4MB of physically installed RAM and you could use Compact Virtual to establish a swap file on a RAM disk that used that additional physical RAM on the accelerator; or
c) Something else?

The issue I'm having is my accelerator only reports 4MB of RAM as being physically installed when using the Applied Engineering control panel, or TattleTech etc.

There is a post on AppleFritter (below) from 10 years ago regarding these boards. This, coupled with AE's marketing materials that indicate these accelerators do NOT support Virtual but DO support > 4MB of RAM, makes me think they worked in a different way than typical. The below indicates the board had to be physically modified (I'm assuming an update to the CPLD or GALs). What's odd though, is in ads/ marketing materials for these accelerators at the time, I do not see any disclaimers indicating the boards RAM functionality was limited.

From AppleFritter:

In practice, when the board first shipped, Applied Engineering warned me that until they ironed out some bugs and released a patch, I'd be limited to 4 MB. I bought it anyway, AND optimistically shelled out for the full 16 MB, which was more expensive than the accelerator board itself! I'm not sure that's a good comment on my judgment, but I did it.

It took something like 18 months but eventually they sent out an email about getting the update to be able to use the full 16. It wasn't a software patch; I had to remove the accelerator board and mail it to them and they'd alter it physically in some unspecified fashion and mail it back.

It worked! Not only did I have 16 MB of RAM on a Mac SE, I had 16 MB of RAM even under System 6! The largest contiguous chunk of RAM was 4 MB (or lower if I launched enough apps to eat more than 12 MB). That gives some clue as to how they did it. But I had a blisteringly fast little toasterMac with enough RAM to thrive under 6.0.8 (with MultiFinder, finally) and, 7.1.

 

[ObeyDaleks]

The way I see it, if you swap the CPU for a full 030, the worse than can happen is that you’re still stuck at 4MB. But if it works, you would likely not only quadruple your RAM, but you would also see significant RAM speed increase. From my experience with similar accelerators, their RAM access speeds are much faster than the original Mac because they use the card’s own bus and completely ignore the original CPU and RAM. You essentially have a whole computer on an accelerator card.

Sounds like a fun project. IMHO, the biggest hurdle would be sourcing a genuine 030 at 40MHz (at a reasonable price).

 

[superjer2000]

The way I see it, if you swap the CPU for a full 030, the worse than can happen is that you’re still stuck at 4MB. But if it works, you would likely not only quadruple your RAM, but you would also see significant RAM speed increase. From my experience with similar accelerators, their RAM access speeds are much faster than the original Mac because they use the card’s own bus and completely ignore the original CPU and RAM. You essentially have a whole computer on an accelerator card.

Sounds like a fun project. IMHO, the biggest hurdle would be sourcing a genuine 030 at 40MHz (at a reasonable price).

The accelerator is already using the onboard RAM (not the motherboard RAM) so it's already running at top speed. This is evident as I can run with only 1MB on the motherboard but it still reports 4MB (ie the accelerator RAM) plus I can tell just from the speed it's running at it is using the RAM on the accelerator (in comparison to say a Classic II with a 16bit data path).

 

[Realitystorm]

Mine has a jumper for 4MB and 16MB, after adding the full processor I could access the full 16MB with compact virtual. It came with 4MB and the EC CPU

 

[Realitystorm]

https://68kmla.org/bb/index.php?threads/mobius-030-16mb-ram.44805/

 

[superjer2000]

https://68kmla.org/bb/index.php?threads/mobius-030-16mb-ram.44805/

Thanks. I had read that thread when doing my research. The key difference though is the recognized physical RAM.

In that thread you had noted:
Yup, Mobius driver (without Virtual) mentions 16MB of onboard RAM.

My card only shows 4MB as being physically installed on the accelerator card even though I have 16mb installed. Now I am taking that from the AE control panel (as well as tattletech and Speedometer). It looks like you had also tried the AE control panel which reported 4MB in your case. So maybe I should see if, somehow, the Mobius software can see the 16MB on my AE Transwarp.

I will give that a shot. If it turns out that the Mobius software can see the 16MB that would give me some hope that a CPU swap might be beneficial.

I haven't ever used an accelerator that needed Virtual to access more RAM. Out of curiosity, does it actually create a mounted RAM disk for the swap file, or does that sort of happen behind the scenes?

 

[superjer2000]

Thanks. I had read that thread when doing my research. The key difference though is the recognized physical RAM.

In that thread you had noted:
Yup, Mobius driver (without Virtual) mentions 16MB of onboard RAM.

My card only shows 4MB as being physically installed on the accelerator card even though I have 16mb installed. Now I am taking that from the AE control panel (as well as tattletech and Speedometer). It looks like you had also tried the AE control panel which reported 4MB in your case. So maybe I should see if, somehow, the Mobius software can see the 16MB on my AE Transwarp.

I will give that a shot. If it turns out that the Mobius software can see the 16MB that would give me some hope that a CPU swap might be beneficial.

I haven't ever used an accelerator that needed Virtual to access more RAM. Out of curiosity, does it actually create a mounted RAM disk for the swap file, or does that sort of happen behind the scenes?

I tried installing the Gemstart drivers (Universal installer, trying multiple different accelerator options). In all cases, the control panel didn't recognize any of the onboard RAM on the Transwarp. (For certainty though, the accelerator is undoubtedly using the accelerator RAM and not the motherboard RAM). As noted before, the Applied Engineering control panel only reports 4MB of RAM as being physically installed (rather than 16MB). Based on all of this, I'm quite confident that replacing my EC processor with a full 030 would only allow me to use disk based virtual memory and wouldn't allow me to access the full 16MB of RAM. My guess is AE did something to disable recognition of > 4MB until they sorted out whatever issues were outstanding as per the AppleFritter post I referenced above.

Given all of this, and the lack of documentation and community familiarity with this particular accelerator, I think I just need to live with this solution as a very fast, but memory constrained, Macintosh Classic.

 

[jmacz]

That’s what I resigned myself to when I had a TW1340 and I saw the same Apple Fritter post. But mine did show the 16MB to compact virtual, it just wouldn’t let me use it and allocate it as a RAM disk. It complained about the lack of a 68030 even though it was accelerating so in my case a full 030 would have worked. But I don’t have the card anymore.

 

[superjer2000]

That’s what I resigned myself to when I had a TW1340 and I saw the same Apple Fritter post. But mine did show the 16MB to compact virtual, it just wouldn’t let me use it and allocate it as a RAM disk. It complained about the lack of a 68030 even though it was accelerating so in my case a full 030 would have worked. But I don’t have the card anymore.

I didn't see any place in Compact Virtual to get information on installed RAM. When I open the control panel, it immediately complains about the lack of an MMU or 040 - after I click OK, the control pan does show a slider that goes up to 16MB, but my assumption is that it would show that irrespective of how much RAM is installed on the TransWarp. I hadn't tried to put, say 4MB on the TransWarp to see if the maximum value of the Compact Virtual's slider would then show 4MB. I had guessed that 16MB might have been the maximum Compact Virtual supported and so it would just always show this, given that it likely stopped doing any further checks on the hardware after determining the MMU was missing.

To confirm, did you ever install less than 16MB on your TW1340 and see that reflected in the Compact Virtual control panel?

EDITED: I found the manual for Compact Virtual and confirmed it will always show a slider maxing out at 16MB irrespective of how much memory it thinks is in the computer.

 

[ObeyDaleks]

So to clarify, Compact Virtual control panel just allows you to set the amount of memory to use. To actually see the allocated RAM, you just use the About My Macintosh dialog as usual. You don’t have to worry about RAM disks or anything like that (since you were asking).

P.S. Oh and also, if I remember correctly, during install, you get to choose the card make/model. If the card isn’t listed, sometimes it takes a few tries to find the “closest one”. I believe it requires a reinstall every time.

 

[jmacz]

Yes, I think you guys are right. I must have thought the slider was representative of the amount of memory detected but it wasn’t. But I got the same cpu errors and never got it to work.

 

[superjer2000]

I am still thinking about swapping the processor for a full 030 to (likely) be able to use Connectix Virtual. As far as I can tell though, the regular 68030 in QFP was not made in speeds greater than 33mhz. Is this correct? Do I take my changes running a 33mhz part clocked to 40mhz?