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Success creating new Model II disks with ImageDisk 1.18 and an FDADAP adapter

hideehoo

Experienced Member
Joined
Aug 4, 2015
Messages
126
Location
Prior Lake, MN
Just wanted to share my experience with this. Things went better than expected and my son now have a number of new disks to play with in the Model II.

I have the later rev drive controller card, so I simply unplugged the 50 pin connector from the TRS-80 card, and plugged in into the FDADAP. I left the drive in the Model II and used it to power the drive during the imaging process.



My imaging PC was an old Abit AX5 (Intel 430TX chipset) motherboard running Windows 98. I set the drive to a 1.2MB 5.25" HD Floppy in the BIOS, connected the B: floppy connector (before the twist) to the FDADAP and run TESTFDC from a pure DOS environment with a blank floppy in the Model II drive. Initial results were not good when connected to the motherboard floppy connector.



So I threw in an Adaptec AHA-1542CF, moved the floppy over to it, and much better results.



After that it was simply modifying a few setting in IMD



and away we went.



The NOS Verbatim disks I bought off eBay were hit and miss. Some worked great, others required multiple write attempts and when I removed the disk you could see radial grooves from the head and magnetic the coating was separating. Cleaning the head afterward produced quite a bit of brown "gunk" on the swab. Anyone ever try the IBM Office System 6 disks?

http://www.ebay.com/itm/Vintage-IBM-8-Floppy-Diskettes-Pack-of-ten-NEW-Office-system-6-/281755990740

The index hole looks like it's in the single sided position and I'm pretty sure IBM used soft sectored disks in that application.
 
Thanks for this. I'm about to get my 8in imaging setup working as well. Did you need to do anything special to get the Adaptec AHA-1542CF working as the FDC in the PC, such as a BIOS setting? Or does IMD work directly with the Adaptec AHA-1542CF? Thanks!
 
To get the AHA-1542CF working, I simply disabled the motherboard floppy controller in BIOS, and enabled the floppy controller on the Adaptec card via it's DIP switch. IMD then sees it just like any other floppy drive, either A: or B: depending on which connector you plug into the FDADAP. Remember, PC floppy are actually set as DS2 (not DS1) so if you want your internal 8" TRS-80 drive which is set to DS1 to show up as A:, you need to plug it into the B: drive connector on a standard PC floppy cable, of use a straight through 34 pin cable between the PC and the FDADAP.
 
Looks like I'm seeing the same errors as you with TESTFDC. So, just ordered a Adaptec AHA-1542CF. Luckily, they seem to be in plentiful supply.
 
I have the older AHA-1522A in my tweener system and it also does single density with no problems. One thing with these boards is you might want to disable the onboard SCSI BIOS to speed up the booting process.
 
Yup. The National 8477 and Intel 82077AA-1 have basically the same pinout, but the Intel chip is broken in single-density mode. Way back when Intel introduced the AA-1 revision (earlier versions of the chip worked), they admitted that they'd broken the chip to add tape drive support and that they had no intention of fixing things. Micro Solutions had to swap the chips out in their Compaticard IV after customers noticed it. Fortunately, they'd socketed the chips...
 
Nice, and looking closely at a couple of other 1542CFs on eBay, I see a big "i" poking out next to the stickers suggesting those have the Intel 820778L instead. Apparently they did switch or mix chips at some point.

So the AHA-1542CF versions with the NSC chips, which were also used on earlier cards, would support the 128 byte DD sectors, but the versions with the Intel chips would not.
 
So I installed an AHA-1542CF with the NSC chip and set it up as the floppy controller.
IMG_0882.jpg
I then ran TESTFDC but everything failed.
IMG_0883.jpg
I tried different drives, all sort of settings, etc. Spent a few hours on it. Then, I decided to go ahead and create a disk and guess what? It worked fine!
IMG_0884.jpg
I can create Model II SS and Model 12 DS disks.
IMG_0886.jpgIMG_0885.jpg
I'm pretty psyched now! But, I'm a little concerned about the TESTFDC errors. Also, there are a few IMD images I have found that are failing to write. Not sure if they are corrupt IMD files or if there is still a problem with my setup.
 
It looks like I can only image Tandy disks for some reason. When I try lsdos, dosplus or cpm it fails. I imagine it has to do with the the different number of sectors/sizes? Do the sector counts/sizes on the dosplus and cpm images below look correct to you? Thanks!
IMG_0889.jpgIMG_0888.jpgIMG_0887.jpg
 
To resurrect an old thread, I'm trying to add an 8" drive to my disk writing system so I can write floppies for my Model II. I have an FDADAP and FDDC. I'm using a TM848-02. The onboard FDC on the system fails all the tests in TESTFDC. I have an Adaptec AHA-1542CF but it will not work in the system (an Abit VH6). It give an error about not being able to enable/disable shadow RAM no matter what address I set and if I disable the BIOS it doesn't work at all. I see hideehoo used an Abit AX5 but I don't see any on eBay. I was going to try my Compaticard IV but it's not working.

I think changing the motherboard would be my best bet. So Pete and Frank, what motherboards are you using?
 
To resurrect an old thread, I'm trying to add an 8" drive to my disk writing system so I can write floppies for my Model II. I have an FDADAP and FDDC. I'm using a TM848-02. The onboard FDC on the system fails all the tests in TESTFDC. I have an Adaptec AHA-1542CF but it will not work in the system (an Abit VH6). It give an error about not being able to enable/disable shadow RAM no matter what address I set and if I disable the BIOS it doesn't work at all. I see hideehoo used an Abit AX5 but I don't see any on eBay. I was going to try my Compaticard IV but it's not working.

I think changing the motherboard would be my best bet. So Pete and Frank, what motherboards are you using?

I've been using an Abit KV8PRO, which handles everything except 128 byte sector MFM, which hardly
anything uses.

The KV8PRO takes an Athlon CPU, with onboard 10/100/1000 ethernet, 1
AGP 8X/4X slot, 5 PCI slots, SATA and IDE drive support, and 4 USB ports.
 
I've been using an Abit KV8PRO, which handles everything except 128 byte sector MFM, which hardly
anything uses.

The KV8PRO takes an Athlon CPU, with onboard 10/100/1000 ethernet, 1
AGP 8X/4X slot, 5 PCI slots, SATA and IDE drive support, and 4 USB ports.

No ISA slots? Since this is what I use to read and write floppies for multiple systems (TRS-80 and CP/M) I want to be able to handle as many formats as possible.
 
No ISA slots? Since this is what I use to read and write floppies for multiple systems (TRS-80 and CP/M) I want to be able to handle as many formats as possible.

The FDC on the KV8PRO will natively read/write FM and MFM disks - no need for the Adaptec 1542-CF.
 
Perhaps he wants 128 byte sector support that he says it does not have?

Anyway, I have been playing around with trying to use a similar ISA Adapter card in an ABIT KT7A. So far no luck. Even after disabling the onboard FDC in BIOS it dosn't seem to want to talk to an FDC in the ISA slot.
 
Perhaps he wants 128 byte sector support that he says it does not have?

Anyway, I have been playing around with trying to use a similar ISA Adapter card in an ABIT KT7A. So far no luck. Even after disabling the onboard FDC in BIOS it dosn't seem to want to talk to an FDC in the ISA slot.

I had exactly the same problem with a 1542B and the Abit KT7A. According to my notes, the IRQ for the floppy controller could not be assigned to the ISA slot.
 
It's interesting reading my old posts on this subject. As an update, my current setup seems to be able to read/write most Model II floppies of different OSes. I know little about PC motherboards, but I've linked to some pics of my imaging machine's motherboard and the adapter I am using.

https://imgur.com/a/rMH0e0P
 
Hello all,

I found this thread looking for info on the FDADAP before I buy one for connecting shugart drives to my imaging PC so I'll add my machine into the mix. It seems Abit and ASUS boards are popular because they all include a WinBond SuperIO chip which still supports all manner of floppy standards if your BIOS will allow. Mine is an Abit KT8Pro running Win98 and Linux Mint. I too fell over the differences between floppy chips on the Adaptec AHA1524CF controller in an older ISA-based machine so I have an intel one if anyone's interested. I know someone who has an AHA1511 spare but he's not the most reliable of people.

The secondary reason for buying an FDADAP is a friend has an old 80s analogue synthesizer used on many hit records back then, the PPG 2.2. Along with the PPG he has the Waveterm "A" add-on which is essentially an Eltec 6809 board running FLEX-9 that originally was connected to a pair of 8" floppies. Later on these were upgraded to 5.25" 1.2mb drives but they didn't change controllers, they simply made a 50 pin to 34 pin adapter and altered the circuit so that 5.25" drives *just* worked. Writing images on a PC 1.2mb drive has proven problematical so with the adapter I can connect the Waveterm drives (YE-Data YD380) directly to the PC.

Hopefully :D
 
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