I might be getting somewhere! And a lot of it is due to my stupidity.

I started digging through threads I _know_ I've read before, especially from Cloudshatze who is who I first picked up on the Trantor T-128 working in Tandys from. He also indicated FDISK only seeing about one-third the disk space available. I've read this a few times but my brain blanked. He confirmed that the only way to get this to work was to use TFORMAT. So I decided to double up my efforts there.

This is what led to me feeling _really_ stupid. TFORMAT has failed every time I tried, and I did briefly dabble in trying to to get the ASPI drivers to work, but it always indicated no SCSI adapter found too. It turns out that I was using the wrong one. MA120.SYS is the correct one. It supports the 120, 128, and a couple other models. Immediately, booting from floppy, it saw the SCSI adapter, followed by the SCSI2SD!

I gave TFORMAT another try, and sure enough, it saw the SCSI2SD and so using the /L (low-level format) and /S60 (for sector size) switch, I started low-level formatting the drive. This is where I ran into the exact same thing I noticed with FORMAT C: /S - namely that the drive activity light would go solid. TFORMAT gives a bit more detail than FORMAT, and you could see it just grinding, one cluster at a time, usually 15-30 seconds per cluster. This could take months, literally, as the low-level format has to churn through about 32K of these.

So taking the advice here, I did two things - I swapped SCSI cables again _and_ I turned off termination on the SCSI2SD. TFORMAT is now churning through a few clusters per second. I expect 30-60 minutes to complete, which for an old 8 Mhz Tandy w/ an 8-bit SCSI adapter on a 1 GB drive, I imagine is about right. When done though, I'm going to test the cable and termination individually to see which might have made it work. I'm still confused as to how disabling termination actually allows this to work at all. Does anyone know what might cause that? The SCSI2SD manual states that if termination is off, and it needs to be on, that small transfers might work, but large ones will fail. I'm just surprised it works, period.

So now I wait until the low-level format completes. This is pretty exciting though! A 1 GB partition on a 25-year old 286 Tandy is kind of overkill, but eh. 😀

I don't recall having to do a low-level format with the TFORMAT utility, for what it's worth.

EDIT: I wrote the following before I saw Thallanor's reply on » 2019-4-13 @ 08:10 - I didn't realise there was a new page to the thread.

Are you able to use a more standard 16-bit ISA SCSI card in your system? I use mine with a AHA-1540/1542CP, but also tested the cheaper AHA-1520/1522B. These Adaptec controller support up to 8 GB drives. So I setup SCSI2SD as an 8 GB drive and use FDISK to partition it into two 2 GB partitions and leave the remaining 4 GB unallocated. I've almost filled up 2 GB on my 386 and cannot imagine filling up more than a second 2 GB.

If your system can only use this particular 8-bit ISA SCSI card, I'd send Michael at SCSI2SD an e-mail asking if anyone has had issues with a Trantor T-128 and HDD sizes showing up much smaller than they are set for. I'm sure he must have run into this and found a solution by now.

Cloudschatze wrote:

I don't recall having to do a low-level format with the TFORMAT utility, for what it's worth.

You are correct! A low-level format was not required. 😀

feipoa wrote:

EDIT: I wrote the following before I saw Thallanor's reply on » 2019-4-13 @ 08:10 - I didn't realise there was a new page to the thread.

Are you able to use a more standard 16-bit ISA SCSI card in your system? I use mine with a AHA-1540/1542CP, but also tested the cheaper AHA-1520/1522B. These Adaptec controller support up to 8 GB drives. So I setup SCSI2SD as an 8 GB drive and use FDISK to partition it into two 2 GB partitions and leave the remaining 4 GB unallocated. I've almost filled up 2 GB on my 386 and cannot imagine filling up more than a second 2 GB.

If your system can only use this particular 8-bit ISA SCSI card, I'd send Michael at SCSI2SD an e-mail asking if anyone has had issues with a Trantor T-128 and HDD sizes showing up much smaller than they are set for. I'm sure he must have run into this and found a solution by now.

Unfortunately, the Tandy 1000 TL/2 only has 8-bit slots. (It's a pseudo XT/AT hybrid machine. A real treat at times!) But I did find a solution!

Using the MA120.SYS ASPI driver allowed me to run TFORMAT finally, as mentioned earlier. But I continued to struggle with getting it to partition and format correctly. I set the SCSI2SD to 1 GB and what would happen is TFORMAT would break. When copying system files to the new partition (a function that TFORMAT does on its own), it would throw an error after just one or two system files, and then it'd start churning through clusters as it setup the drive. And then it would just churn... and churn... and churn. I'd come back and the cluster number had actually rolled over (I presume hitting an integer limit) and was now a negative number, increasing to 0 and just continuing on again until once more, it'd roll over into the negatives and keep going. It did this for about three hours before I aborted it.

I then tried 1,000 MB. It worked! So I tried 1,023. It didn't. So I kept splitting the difference and finally found (I'd need to confirm on the SCSI2SD itself but am not there at the moment) that 1,019 MB worked. Anything more, and it'd act as previously described. I can now boot from the SD and it's fast! I mean, fast given it's a 25-30 year old 8 MHz 286. 😀

The only thing (and this is me being nitpicky) is I'd love to find the math regarding the SD's cylinders and also TFORMAT's calculation of clusters too in order to find out specifically the size I can make the SD. (Like 1,019.xx MB for example.) Again, this is just me being anal - this is more space than I'll need for this PC but it's nagging at me. 😀 If anyone has any suggestions, I'm all ears. I know that roughly (but not exactly) the clusters appear to be almost double the cylinders. (i.e. Around 33K cylinders, around 64 or 65K clusters - I think this is where we're rolling over the integer and finding the breaking point for this controller card and/or TFORMAT.) I did some basic math last night though and thought the MB limit would be closer to 1,008 but that was assuming a 65,535 integer limit so maybe my math is wrong...)

Any suggestions are appreciated but honestly, I'm just thrilled this is working! 😀

If you want a challenge, how about setting SCSI2SD for two HDD's of 1019 MB? Will your system accept two HDDs?

feipoa wrote:

If you want a challenge, how about setting SCSI2SD for two HDD's of 1019 MB? Will your system accept two HDDs?

Hah!

Unfortunately, it seems the moment the total partition size exceeds that number (~1,019 MB), issues arise. I created four 512 MB partitions wondering if that would work. FDISK didn't see any drives and if memory serves, TFORMAT saw them, copied system files to each one (I guess you gotta be really sure. 😀 ) but rebooting from the SD, it only saw drive C:. It didn't recognize that any of the other partitions were there. 🙁

I'd be interested in testing to see if it works if I created a 512 GB partition and then a really small partition, just to be sure I don't exceed !,019 MB, and see if both are recognized that way.

Another thing I was curious to try was setting one of the other drives to be a CD-ROM, magneto-optical, or floppy disk. No real reason other than seeing if it worked. But if it did work... I wonder if they might ever update SCSI2SD and/or it's utility software to allow you to mount floppy IMG files to the drives? That would be so awesome.

Do you have an e-mail address for the SCSI2SD creators, BTW? I took a quick peek but didn't see much. I might poke them about this and about FDISK not seeing the drives in general. While TFORMAT works, my understanding is that FDISK should too.

I'm still pretty happy with how this has gone though. 😀

feipoa wrote:

Are you able to use a more standard 16-bit ISA SCSI card in your system? I use mine with a AHA-1540/1542CP, but also tested the cheaper AHA-1520/1522B. These Adaptec controller support up to 8 GB drives. So I setup SCSI2SD as an 8 GB drive and use FDISK to partition it into two 2 GB partitions and leave the remaining 4 GB unallocated. I've almost filled up 2 GB on my 386 and cannot imagine filling up more than a second 2 GB.

Dunno whether this is valid for older Adaptecs. They had originally a 2GB limit.
The notes on Microsemi say that (at least for the AHA-1542CF) one needs the latest BIOS to get 8GB drives supported.
Whats fine too is that the latter host adapter is of truncating type, so it recognizes and uses drives >8GB too, albeit only the first 8GB.

All my Adaptec 1540CP and 1542CP cards work with 8 GB drives.

I might still dig for SCSI2SD support because the more I think about it, the more I wonder if it is something with my SCSI2SD v6. So long as I'm below 1,019 MB _total_ then everything works well. But the moment I even add a second drive on the SD card through the SCSI2SD, things break. It's my opinion that all of that "math" should be happening on the SCSI2SD itself. Yeah, if I exceed a certain size, I expect the SCSI controller and/or OS to barf. But so long as I stay below that limit, I would think I should be able to add as many additional drives on the SD card as possible. It's almost as though the SCSI2SD is having trouble addressing anything beyond 1,019 MB.

So yeah, I might see what I can find for contact details. 😀

I believe Michael's email is written on the SCSI2SD PCB itself, so that shouldn't take much research. I think your issue is the SCSI controller. I've had SCSI controllers not work beyond 1 GB.

Though, it is possible that there is an issue with setting up multiple HDD's on SCSI2SD. I recall having an issue with that. I may be mistaken, but doesn't DOS and/or your SCSI controller only support one primary partition? So wouldn't the second HDD need to be setup as a logical drive? Because I didn't want to research that issue, I just setup my SCSI2SD as a single 8 GB drive and made a few 2 GB partitions, but of course, my SCSI controller supported up to 8 GB.

feipoa wrote:

I believe Michael's email is written on the SCSI2SD PCB itself, so that shouldn't take much research. I think your issue is the SCSI controller. I've had SCSI controllers not work beyond 1 GB.

Though, it is possible that there is an issue with setting up multiple HDD's on SCSI2SD. I recall having an issue with that. I may be mistaken, but doesn't DOS and/or your SCSI controller only support one primary partition? So wouldn't the second HDD need to be setup as a logical drive? Because I didn't want to research that issue, I just setup my SCSI2SD as a single 8 GB drive and made a few 2 GB partitions, but of course, my SCSI controller supported up to 8 GB.

I'm actually not certain how this works, now that you mention it.

When I first used the SCSI2SD software, I thought that when you split up the SD card, the end result was multiple drives (you have to select a different ID for each one). So this would be different from multiple partitions, as all of the magic goes on in the background. But then I got confused since this is all one device. I am going on a limb by suspecting that the SCSI2SD also does this magic internally too. One ribbon connector, but internally, appearing as multiple devices. That's the only way it would really make sense. But for this reason, I don't think the issue is a size limit with the Trantor either, since it should just see multiple devices. In fact, now that I think about it, when I created a couple small test drives using SCSI2SD, the Trantor software did in fact see it as two completely separate drives and formatted them individually.

I'll reach out and see what sort of answer I get. 😀

infiniteclouds wrote on 2019-04-11, 19:31:

I managed to find this card. It has the same FCID as the Rancho card that Cloudschatze uses and I think that at the very least i […]
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I managed to find this card. It has the same FCID as the Rancho card that Cloudschatze uses and I think that at the very least it can use the same BIOS, if it doesn't already have it on there. I have yet to test it.

It is labeled SYSGEN Inc. but it also has "RT1000B" on there.

Please dump its ROM so it can be archived (and copied to my machine 😉

--Fred