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Powertran Cortex Issues

So @fixit9660 got himself a Gotek which prompted me to dig the cortex back out and have a proper look at getting some disk images working.... and as it turn out I'm an idiot. The crap gotek drives (like the one i'm using) don't have much memory at all so are quite reliant on the SD card/memory stick for speed. So I "aways" use a decent modern card in them for raw files. Slower cards are fine for more basic disk images. I made sure I had a decent card in before I started this months back....... and then somewhere along the line I've picked up the wrong card reader (i have a few of the exact same mini reader for different devices) and have unbeknown to me been using a crap slow SD card. The result of which was a failure to write the disk image to the gotek via the PC util at almost exactly the same point (somewhere around track 5 on a DD image and further on a SD image) which in hindsight was probably a good indication it had run out of buffer memory.
Anyway, I've gone back to the start and got a basic config for the gotek hardware and no disk image config (img.cfg) because I'm working with raw files, and I have managed to get a full copy of CDOS 1.2 written to a DS DD 80 track hfe file. As long as you don't have the SD jumper on this disk boots fine and can be written to. So not only is this a good sign that we can write ok to a gotek with the cortex, but also that I now have a full raw disk image that could possibly be analyzed and used to help make a config to boot the existing disk images, and I haven't had to prat about with real (unknown quality) floppies and real (unknown functional) drives and then having to image them with my greaseweazle.
Attached is a zip file with the CDOS 2.1 boot disk image, a blank DS DD 80track disk image (with a print hello basic test) and a base config file, just put the files in the root of a FAT32 pen drive and it should boot.
You could also add the previous image I made but it would need the SD jumper on or the memory address patched to boot.
 

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plagued said:
So @fixit9660 got himself a Gotek which prompted me to dig the cortex back out and have a proper look at getting some disk images working.... and as it turn out I'm an idiot. The crap gotek drives (like the one i'm using) don't have much memory at all so are quite reliant on the SD card/memory stick for speed. So I "aways" use a decent modern card in them for raw files. Slower cards are fine for more basic disk images. I made sure I had a decent card in before I started this months back....... and then somewhere along the line I've picked up the wrong card reader (i have a few of the exact same mini reader for different devices) and have unbeknown to me been using a crap slow SD card. The result of which was a failure to write the disk image to the gotek via the PC util at almost exactly the same point (somewhere around track 5 on a DD image and further on a SD image) which in hindsight was probably a good indication it had run out of buffer memory.
Anyway, I've gone back to the start and got a basic config for the gotek hardware and no disk image config (img.cfg) because I'm working with raw files, and I have managed to get a full copy of CDOS 1.2 written to a DS DD 80 track hfe file. As long as you don't have the SD jumper on this disk boots fine and can be written to. So not only is this a good sign that we can write ok to a gotek with the cortex, but also that I now have a full raw disk image that could possibly be analyzed and used to help make a config to boot the existing disk images, and I haven't had to prat about with real (unknown quality) floppies and real (unknown functional) drives and then having to image them with my greaseweazle.
Attached is a zip file with the CDOS 2.1 boot disk image, a blank DS DD 80track disk image (with a print hello basic test) and a base config file, just put the files in the root of a FAT32 pen drive and it should boot.
You could also add the previous image I made but it would need the SD jumper on or the memory address patched to boot.
Click to expand...
Hey Excellent news @plagued!! Nice one. I've downloaded your file, thanks. I don't know anything about the configuration of this, and I need to do some serious reading to start to understand it. All I've done so far is attach the GoTek "as supplied" with FlashFloppy+ installed by the author keirf, and with DS1 jumper in, but when I do this the floppy drive DS0 stops working, so the GoTek is obviously interfering with the drive identification somehow. keirf has confirmed that "as supplied" the GoTek should work but that's as far as I've gotten. More work needed here.
 
the config file is pretty generic, it's telling it to behave like a shugart drive using the flashfloppy's own ti99 profile. There's some other guesswork figures in there that may or may not help/hinder :) so it's more just how I thought it .. maybe... wanted to be. The config related to the rest of the drive setup I've also left generic, most things are set to auto and I've left in the option for things like the rotary encoder and bleeper (so it makes floppy drive noises) even though I don't have them currently installed. So in theory it all should work on any Gotek running flashfloppy 3+
The real complex bit here would be working out what we need to go in an img.cfg file to allow it to emulate the existing dsk files the cortex emulator uses so I don't have to remake them all as raw flux files.
Regarding the second drive, I think I did manage to get it running alongside the Mitsubishi BBC Micro drive I was using for testing, but I had to remove the MX jumper that messed with motor on and drive select, which is probably not a gotek issue, and more a cortex one, where this mitsubishi drive would have always needed the MX jumper removed when working in a dual drive setup. I'd just never tried using either the Gotek or the Mitsubishi drive in a dual drive setup on the Cortex before only individually. The twin drives the Cortex came with are almost useless SS SD 40 track drives :)
 
ok, update from todays poking... (that's what she said)
I can get the Gotek playing fine with my physical drive, so gotek as 0 and booting disks and physical drive as 1 and reading and writing.
The image I made does not seem to have a recognisable format :(
I do have crap unreliable floppies, and they were responsible for my earlier failures to write a full disk (does that make me a bad workman if my tools are actually to blame???) After trying a few different ones I have got a physical DS DD 80 track disk written and booting.
I have imaged that physical disk with a greaseweazle to see if it would uncover anything else... but it doesn't, it does give a full raw flux disk image (with an unrecognised format) which may have something the hfe file doesn't which may be useful for analysis.
I have also taken that raw flux image and converted it back to a hfe file and can boot it with the Gotek..... so I may be at my limit of what I can do to make a config that will run standard dsk images. Maybe one to post up on the flashfloppy forum.
But I can reliably copy Cortex floppy disks on my PC and convert them to disk images that will work fine on a Gotek and also re image all the existing ones into new Gotek compatible hfe files ... it would just take quite a while.
attached is all the different versions of the same CDOS 1.2 disk.
 
plagued said:
ok, update from todays poking... (that's what she said)
I can get the Gotek playing fine with my physical drive, so gotek as 0 and booting disks and physical drive as 1 and reading and writing.
The image I made does not seem to have a recognisable format :(
I do have crap unreliable floppies, and they were responsible for my earlier failures to write a full disk (does that make me a bad workman if my tools are actually to blame???) After trying a few different ones I have got a physical DS DD 80 track disk written and booting.
I have imaged that physical disk with a greaseweazle to see if it would uncover anything else... but it doesn't, it does give a full raw flux disk image (with an unrecognised format) which may have something the hfe file doesn't which may be useful for analysis.
I have also taken that raw flux image and converted it back to a hfe file and can boot it with the Gotek..... so I may be at my limit of what I can do to make a config that will run standard dsk images. Maybe one to post up on the flashfloppy forum.
But I can reliably copy Cortex floppy disks on my PC and convert them to disk images that will work fine on a Gotek and also re image all the existing ones into new Gotek compatible hfe files ... it would just take quite a while.
attached is all the different versions of the same CDOS 1.2 disk.
Click to expand...
I haven't had the chance to do any research on the GoTek so I apologise for these questions.
My "as-supplied" GoTek won't work as Drive 1 with my Floppy as Drive 0, in spite of the GoTek DS Jumper set on S1 (as-supplied). I don't know why. It's like it thinks it's Drive 0 in spite of the Jumper set to S1.
I can't use my GoTek as Drive 0 because:
a) it needs a specific config file loaded first? Loading your FF.CFG file onto a USB stick formatted as FAT32 and placing it in the Root directory of the GoTek should accomplish this?​
b) if I place your CDOS_1_2_DS_DD.hfe file on the USB in the same Root directory as the FF.CFG file it will make it Bootable?​
c) These are the only files I need on the USB stick to make it work?​
The Cortex should be able use the GoTek as a conventional Floppy Drive at this point. I hate asking things like this but life is hindering progress and I'd just like to get to the point where I know the GoTek is working.
 
a) In theory the Gotec should do what the drive select jumper tells it. but without a config file it will be in a default mode. There's some lines in the ff.cfg I provided that can help ensure it behaves in the correct manor, without them it will just be in some generic (probably IBM PC) floppy mode:
interface = shugart #This may well be your issue. it may be defaulting to expect a twisted cable, which you're not using. Specifying shugart tells flashfloppy how it's wired
host = ti99 #This may not be doing much - I currently have it set to host = unassigned while I've been testing stuff and it boots fine like this
pin02 = auto #This is probably the default behaviour but in auto it correctly detects the drive select
pin34 = auto #As above with the ready pin
There is one slight caveat that I don't know what display you have or encoder dial .. but it's set to generic settings so "should" work.

b) yup, a hfe file is effectively raw disk data, so rather than store the 0 and 1 that are stored on the disk (like the other dsk files) it's storing the actual raw flux data that then needs to be read by a drive to turn into the 0 and 1 needed. This means it doesn't need an img.cfg to tell the gotek how to present the 0 and 1 from the image as a floppy disk because, in essence, it is one, so as long as the ff.cfg has told the gotek what type of floppy drive it is pretending to be, it just plays the disk. the left/right buttons or the encoder dial should let you select which image is loaded. If there's only 1 I'd have thought it would auto select it.

c) yup, just dump those files on a pen drive and poke it in the gotek. You can hot swap the USB stick so it doesn't need to be in before you boot. The display should show the file name and you should also see on the right the track that the disk is sat on (which is handy as you can see how it behaves, like with the dsk images I can't boot you can see the cortex bouncing between tracks 0 and 2 looking for the boot sector).
 
plagued said:
a) In theory the Gotec should do what the drive select jumper tells it. but without a config file it will be in a default mode. There's some lines in the ff.cfg I provided that can help ensure it behaves in the correct manor, without them it will just be in some generic (probably IBM PC) floppy mode:
interface = shugart #This may well be your issue. it may be defaulting to expect a twisted cable, which you're not using. Specifying shugart tells flashfloppy how it's wired
host = ti99 #This may not be doing much - I currently have it set to host = unassigned while I've been testing stuff and it boots fine like this
pin02 = auto #This is probably the default behaviour but in auto it correctly detects the drive select
pin34 = auto #As above with the ready pin
There is one slight caveat that I don't know what display you have or encoder dial .. but it's set to generic settings so "should" work.

b) yup, a hfe file is effectively raw disk data, so rather than store the 0 and 1 that are stored on the disk (like the other dsk files) it's storing the actual raw flux data that then needs to be read by a drive to turn into the 0 and 1 needed. This means it doesn't need an img.cfg to tell the gotek how to present the 0 and 1 from the image as a floppy disk because, in essence, it is one, so as long as the ff.cfg has told the gotek what type of floppy drive it is pretending to be, it just plays the disk. the left/right buttons or the encoder dial should let you select which image is loaded. If there's only 1 I'd have thought it would auto select it.

c) yup, just dump those files on a pen drive and poke it in the gotek. You can hot swap the USB stick so it doesn't need to be in before you boot. The display should show the file name and you should also see on the right the track that the disk is sat on (which is handy as you can see how it behaves, like with the dsk images I can't boot you can see the cortex bouncing between tracks 0 and 2 looking for the boot sector).
Click to expand...
I don't believe this; My USB stick just died! Someone up there doesn't want me to get this going...😣.

If I use the same files as you, (same .CFG), with the S0 jumper in, and no other drive connected it should work. Now where's another USB Stick.....
 
It's not just one dead USB Stick. I now have three dead USB Sticks immediately after using them in the GoTek Drive.😱😱😱 If I connect only the GoTek with S0 jumper in, and try to Boot from it with a USB Memory Stick, formatted as FAT32 with only the CDOS_1_2_DS_DD.hfe and FF.CFG files on it, the Green LED lights but nothing more.
I'll see what zeroflux the Seller on eBay says, but I think the drive must be faulty.
 
oh dear that doesn't sound good. There's not a lot to a gotek it's got the main Artery Arm chip and then a 7404 .. that's it.
I just realise the attachment with the disk images for potential analysis didn't upload because even as a zip it's too big.
The raw flux image of the 640KB disk is nearly 45MB big.
Here's a link to it if anyone's interested: https://drive.google.com/file/d/1cl6cwKlNROqNh2gSObfHdratyjohoPgr/view?usp=sharing
 
plagued said:
oh dear that doesn't sound good. There's not a lot to a gotek it's got the main Artery Arm chip and then a 7404 .. that's it.
I just realise the attachment with the disk images for potential analysis didn't upload because even as a zip it's too big.
The raw flux image of the 640KB disk is nearly 45MB big.
Here's a link to it if anyone's interested: https://drive.google.com/file/d/1cl6cwKlNROqNh2gSObfHdratyjohoPgr/view?usp=sharing
Click to expand...
Thanks for the updated zip file. I've got an idea I need to investigate.... :oops:
 
Oh dear. I'm getting old. I used a standard adapter cable to supply power to the GoTek from the standard floppy drive cable. It supplied +5v AND +12v. I cut the +12v cable out of it and it works fine now. It never occured to me that the Gotek would connect that pin of the power connector if it didn't need it. I think I got away lucky, at least it looks like it so far. I don't know what long term damage I've done though.
The GoTek screen is upside down, but I need to change the "display-type=auto" to "display-type=oled-128x64-rotate" to correct that.
 
Further progress. I can Boot the Cortex reliably from the GoTek. I had to change the motherboard "Size" Jumper to get it to work, which makes me think the disk image is Single Density, but then it doesn't interact with the existing drives, probably for the same reason? At this point I have no idea how to create disk images, other than I think I need to use HxCFloppyEmulator but that's all. I also need to understand how to create multiple "disks" on the same USB Memory Stick, but again more research needed.
 
@plagued re: the gotek_cortex.zip file, the CDOS .hfe file only contains about half of the original CDOS 1.2 Disk files, which makes me think it's a Single Density Disk because they won't all fit on? If you agree, do you have another version with a Double Density disk with all the files on it please?
 
fixit9660 said:
@plagued re: the gotek_cortex.zip file, the CDOS .hfe file only contains about half of the original CDOS 1.2 Disk files, which makes me think it's a Single Density Disk because they won't all fit on? If you agree, do you have another version with a Double Density disk with all the files on it please?
Click to expand...

that hfe disk is the image of "CDOS 1.20 Master Release.dsk" which is a 640k image which would be DD DS 80 track, which is what I formatted the virtual disk to before (very slowly) copying it over via the PC app.
Checking the hex of that file and it's mostly an empty disk. If you boot it on the emulator it's got:

Screenshot 2025-09-11 190123.jpg
Which from memory matches what's on that hfe disk.
I have the top jumper (nearest the back) removed and the bottom jumper fitted. To boot my single density disk image (from much earlier in this thread) I have to fit the top density jumper. So I'm fairly sure it's a DD disk, there's just almost nothing on it.
I'm happy to copy over a new disk ... in fact if anyone has a suggestion of anything good to have I'd love to have a play around. There's a games disk for MDEX, but the only other games I've found are a coupe of .cas files.
I just picked that one as a test because it said "Master" on it :) So let me know which disk image you want me to try and I'll get it pulled over.
 
Thanks for the offer @plagued, I'll do some more research here and may take you up on that. I'm not as well organised as you are yet. ;)
When you load the CDOS 1_20 Master_dsk.hfe file into the HxCFloppyEmulator, what message do you get at the bottom?
I get one including information about it being 84 tracks? There's only 80 tracks on a 5.25" drive.
 
I'll check, but I probably wouldn't read too much into it.
The hfe file behaves like a real floppy disk, it can be formatted in a multitude of ways, it'll just store the flux changes exactly as the drive sends it and, as a file, it won't have any idea what it's format actually is (which is why it's such a pain to analyze because neither the greaseweazle or HxEfloppyemulator recognise the disk format and the file's just raw data). It's possible that I imaged a physical disk with the greaseweazle and didn't add the 0-79 track option to tell the greaseweazle what type of disk I was imaging, and that's the image I then used later for this (you can make raw blank hfe files to any specification without any physical drives involved but I'm fairly sure as I've been imaging real disks with real floppies, any hfe file here will have originated as a real floppy). I know I did 0-79 track option for the CDOS_greaseweazle.hfe so if that file shows 80 tracks and the CDOS 1_20 Master_dsk.hfe shows 84 then it'll just be that the virtual disk file I used to make CDOS 1_20 Master_dsk.hfe didn't have any track info set when imaging it and the software tagged the file as 84 tracks as some sort of safe max number of tracks - I don't believe that means it's what the disk is currently configured as, it's just a tag to say this is what it was imaged as. If they both have a header stating 84 tracks then who knows .....
 
Progress. Using the "CONFIG" to set the "$SYSTEM" file on the GoTek CDOS disk, so that the second, S1, drive config was set as 80 Track, Single Sided and Single Density, after rebooting I could access the floppy drive! :)
I'll post the FF.CFG, IMG.CFG and CDOS $SYSTEM files here shortly.
 
ahh yes, I did have a play at one point with "CONFIG" and ended up braking the disk image and had to copy it over again. I wonder if that could be the issue, a small bit of config data somewhere between tracks 0 and 2 that stores what the drive config is. The issue being, that without that data being there the Cortex won't write to the drive, so you can't fix the issue..... Whatever the issue is, it's in those first few tracks, so it could be a gap issue or an offset or something that means the data isn't where it should be. I'm trying to not have to read back over all the technical papers :p
In the mean time, I've imaged three of the MDEX disks, just to see what it is. Zip attaches with boot/system and games disks, they're all the 40 column versions as I don't have an 80 column machine.
 

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If anyone is interested in watching me bumble my way through this repair/restoration I finally got round to chucking some videos up on youtube.
So here's Part 1 of the restoration
In total it's 3 hours long (and I had to cut a load out including any of the more recent gotek stuff) ... so may be worth watching on 2x :ROFLMAO:
 
plagued said:
If anyone is interested in watching me bumble my way through this repair/restoration I finally got round to chucking some videos up on youtube.
So here's Part 1 of the restoration
In total it's 3 hours long (and I had to cut a load out including any of the more recent gotek stuff) ... so may be worth watching on 2x :ROFLMAO:
Click to expand...
I watched it yesterday in the background while - ahem! - busy working. You documented your adventure very well. ;-)
 
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