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alan8086
September 16th, 2017, 02:29 PM
Good evening! I know this one isn't new, I've read various other forum posts regarding the noadrmark error when using Imagedisk to create exotic floppy disk media.

I have a Pentium 100MHz PC
I have an adaptec AHA-1542CF controller with the correct chipset - not the Intel one. I got it off eBay a few days ago for 13 once I realised trying different equipment I have was futile.
I have my D-Bit FDADAP adapter - now working correctly
I have my NEC APC floppy drive set as drive 1, no drive termination resistor packs
in TestFDC the drive controller passes all the tests
in IMD (imagedisk) I can format floppy disks Ok
when it comes to writing an image to disk, I get constant noadrmark errors. The heads slowly move up to cylinder 11 over maybe 10 mins, giving the adrmark error along the way.
At cylinder 11 it gives up and says 'no signal from FDC'

I've posted a video of my progress. PLEASE SKIP THE FIRST 30 SECONDS - which is blank. I hate video editing!


https://youtu.be/J-wXLt_EauU

I've read elsewhere on this forum that noadrmark is something to do with the sector no 1 hole in the floppy disk, the sensing of it. My understanding goes no further.

Any suggestions are appreciated!

Thanks :)

Chuck(G)
September 16th, 2017, 03:54 PM
First off, on the P4 system, you should be running MS-DOS; not Windows. If you're running Win 9x, the system should be shut down to MS-DOS prompt mode. Running in a DOS prompt window will not work.

If that doesn't fix things, then we need to know what model NEC floppy you have. NEC made some very strange drives--so we need to be sure that you don't have one of those.

AFAIK, the APC uses the standard 8x1024 format, so there should be no problem there.

SomeGuy
September 16th, 2017, 04:51 PM
First of all, the format command in imagedisk does not verify what it has written. It just blast bits out to the disk and doesn't care if the disk is damaged or if there is some other problem.

Try formatting and then reading an image from what it has just written. It should just quietly read all of the tracks, creating a file with blank data. But I suspect you will get piles of errors instead. If so, exactly what error?

You also don't need to format before writing a floppy disk image. Imagedisk automatically tries to reformat to the appropriate format.

The noaddrmark means it can't find the sector on the disk to write to. I am a little surprised you get one for each sector seemingly with no variation. If the disk were bad, I would expect some to succeed and others to fail. It could be that the disk is very, very bad?

Do you have other disks to try?

Off hand, your setup looks correct. And Testfdc does write to the disk - it would fail if there were a problem with the drive, such as a fouled head, preventing writing - but it only writes to one track.

alan8086
September 17th, 2017, 12:17 AM
Hi Chuck - thanks for your reply, its not a Pentium 4 machine its a Pentium 1 as in the first one - at 100MHz Also, Its running MS DOS-6.22, not windows.

Oh - floppy drives are:

NEC Model FD1165-A

alan8086
September 17th, 2017, 12:20 AM
First of all, the format command in imagedisk does not verify what it has written. It just blast bits out to the disk and doesn't care if the disk is damaged or if there is some other problem.

Try formatting and then reading an image from what it has just written. It should just quietly read all of the tracks, creating a file with blank data. But I suspect you will get piles of errors instead. If so, exactly what error?

You also don't need to format before writing a floppy disk image. Imagedisk automatically tries to reformat to the appropriate format.

The noaddrmark means it can't find the sector on the disk to write to. I am a little surprised you get one for each sector seemingly with no variation. If the disk were bad, I would expect some to succeed and others to fail. It could be that the disk is very, very bad?

Do you have other disks to try?

Off hand, your setup looks correct. And Testfdc does write to the disk - it would fail if there were a problem with the drive, such as a fouled head, preventing writing - but it only writes to one track.

THAT is the information I need! Noadrmark means it can find the sector on the disk to write to! Also didn't know Imagedisk formats as it writes. I have one or two other DD 8" floppies that I class as being ok so I'll try with those later. I've cleaned the drive heads but I will do so again as they seem to get dirty depending on which disks I have had it chewing through.

Chuck(G)
September 17th, 2017, 09:02 AM
Here's the OEM manual for the 1165 (http://electrickery.hosting.philpem.me.uk/comp/divcomp/doc/NEC_FD1165_8_inch_floppy.pdf). If you compare the signal and jumper settings to a standard Shugart SA-851 (http://bitsavers.informatik.uni-stuttgart.de/pdf/shugart/SA8xx/39017-0_SA850_851_OEM_Manual_Nov80.pdf), you'll notice several substantial differences.

Inspect the options on your drive and set them so that they correspond to the Shugart standard. As I mentioned before, NEC made some pretty unusual drives.

SomeGuy
September 17th, 2017, 09:42 AM
Make sure the heads are loading (touching the surface of the disk) when the drive is selected. That would be the HL jumper on the drive. The heads not loading could cause the errors seen above.

alan8086
September 17th, 2017, 01:33 PM
Here's the OEM manual for the 1165 (http://electrickery.hosting.philpem.me.uk/comp/divcomp/doc/NEC_FD1165_8_inch_floppy.pdf). If you compare the signal and jumper settings to a standard Shugart SA-851 (http://bitsavers.informatik.uni-stuttgart.de/pdf/shugart/SA8xx/39017-0_SA850_851_OEM_Manual_Nov80.pdf), you'll notice several substantial differences.

Inspect the options on your drive and set them so that they correspond to the Shugart standard. As I mentioned before, NEC made some pretty unusual drives.

Thanks for the advice Chuck - I remember you mentioning different signal lines in another post. I will now let go of my belief that having a FDADAP adapter is a one shot solution! Didn't realise you could alter jumpers to achieve a different standard - I'll have a good look at that manual tomorrow and see what's what.

alan8086
September 17th, 2017, 01:36 PM
Make sure the heads are loading (touching the surface of the disk) when the drive is selected. That would be the HL jumper on the drive. The heads not loading could cause the errors seen above.

...I'll take a look at the HL jumper. I assumed that because formatting a disk in Imagedisk seems to erase what was previously on the disk then the heads must be touching but its defiantly worth checking.

alan8086
September 21st, 2017, 09:20 AM
I've had a look at the OEM 1165 manual linked to above. The jumpers are different on mine, most of the ones described in the manual do not exist on my floppy drive board. Maybe the 1165-A is slightly different? I've tried different motherboards, different floppy disks. Not one correctly written track - just a load of 'Error noadrmark'

Its a real shame as this machine is turning out to be quite reliable. Sometimes it gets a bit sketchy when loading a boot disk - clean the heads and its fine again.

I have a tough, functional vintage computer but no way of creating software for it other than relying on kind souls and donations. Harry knows how that one turned out!

Chuck(G)
September 21st, 2017, 10:33 AM
I'll dig through my own documents and see if I've got something for the 1165-A. There's probably something simple that we're missing.

Chuck(G)
September 21st, 2017, 07:05 PM
Ah, it's what I thought--the APC uses the (unique) VFO capability in the 1165A to do the work of deriving clock and performing data separation. This is also the case for the NEC 5.25" and 3.5' models on some PC98 hardware. Someone has worked up an external board to perform this function with standard drives.

At any rate, see this post (https://forum.kryoflux.com/viewtopic.php?f=4&t=56&sid=0059dd123b8d0218bd00f31052fe3460&start=10#p1587) You've got to change some jumpers. Forget the discussion of the Kyroflux utility.

alan8086
September 21st, 2017, 11:25 PM
Ah, it's what I thought--the APC uses the (unique) VFO capability in the 1165A to do the work of deriving clock and performing data separation. This is also the case for the NEC 5.25" and 3.5' models on some PC98 hardware. Someone has worked up an external board to perform this function with standard drives.

At any rate, see this post (https://forum.kryoflux.com/viewtopic.php?f=4&t=56&sid=0059dd123b8d0218bd00f31052fe3460&start=10#p1587) You've got to change some jumpers. Forget the discussion of the Kyroflux utility.

- Ok, this could be it! I'm at home with my son for the morning so cant get to the APC until later but I'll be sure to report back with the result. Defiantly remember a jumper marked VFO. Manual just says this about it -

1.2.12 Variable Frequency Oscillator (Optional)
The optional VFO makes the interface signals to the controller more stable. This feature increases the overall reliability of the disk drive.

- Honestly, I do my own scour of the internet for solutions to issues but I just wouldn't have had the knowledge or experience to look in this VFO direction. So thank you Chuck - I'll do a write-up of the whole process if I can get this disk imaging for the NEC APC going.

:)

alan8086
September 23rd, 2017, 06:38 AM
40919

success!!


In VFO mode I am able to create working boot disks etc for my APC!

It worked twice - for the two disks that make up the DOS-2.11 set.

I have a few crinckles to iron out - I think I have a dodgy connection somewhere as a successful write only worked twice and the other times it was as if I had put the jumper back to its normal position with VFO off - lots of noadrmark errors plus a few writes. Also seems to help if I erase the disk first but I could just be imagining it?

Next issue is to source some reliable DS DD 8" floppy disks. I have two I am confident are ok which now have DOS on them. I have a stack of hard sectored DS DD floppies, wonder if I could cover up the index holes bar one and use em like soft sectored?

A library of NEC APC software is my goal.

THEN - try and get my IMS 8000 vintage computer working again and Imagedisk its own software library - plus create archive images of the software I have for it.

Thanks again to all of you for your help with this :)

retrogear
September 23rd, 2017, 09:48 AM
I have an NEC1165 drive. It originally was hit / miss on reading / writing but I noticed the head solenoid wasn't always loading the head. Found a rubber bumper turned to sticky tar and just cleaned the surface with some isopropyl. Photo is looking straight down on top easy to get to.

40925


Larry G

Chuck(G)
September 23rd, 2017, 09:52 AM
Some 8" drives (I don't recall if your NEC 1165A is one of them) have on-board logic to separate sector pulses from index pulses; with the output going to a separate pin, usually called SECTOR/ or the like. My Siemens drives have that capability and it's come in handy. I received about 20 8" hard-sectored floppies from a customer, only to discover that sector start didn't coincide with the position of the sector holes. It turned out that the customer had found a bargain in hard-sectored floppies and set his drive up accordingly.

FWIW, unlike 5.25" HS disks, there is only one kind of HS 8" (absent a few very early cases) disks--the 32-sector one. Drives with HS support logic often have a divider chain so that 8, 16 and 32 sector pulses can be output with no external logic.

Absent the appropriate drives, however, you're best off swapping for soft-sector floppies.