High Density Floppy Disks on Commodore 1541?
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- Опубліковано 14 січ 2019
- Can high density 5.25" floppies be used with the Commodore 64/128? The answer is no, and yes. Yes, it sometimes works, but is it reliable? No.
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Check out my podcast Growing Up '80s: thecouch.website/category/gu80s/ - Наука та технологія
Thanks for the shout out! Glad you like the magazine :)
Back then, I remember asking for blank disks for my birthday/Christmas.
I remember in my poor teenage years waiting for the AOL marketing disks so I could format them and get a free floppy! The only ones I would get too...
loved the Micadon ad at the end. that brought up some memories! and i did NOT know that there was an issue with HD floppies, very informative Robin, thanks!
And thanks for your offer of help even though you didn't know what it was about, and it didn't end up being used in the episode anyway! ;)
So glad I found this video...THANK YOU! I am a reseller & typically possess correct product knowledge, but I am not abundantly tech savvy and have somehow managed to obtain a good deal of NIB Gaming Box Sets & Software, as well as, new & used disks. I listed the NIB HD diskettes online & included all the package info for compatibility, assuming the consumer would be searching for specifics based on their need or interest, BUT I received a message this week inquiring about thw compatibility of these disks with thw Commodore 64. YIKES!... I hadn't the slightest clue, but I knew I needed to find out! And so, I DID! ... Thanks to you creating this video! Very helpful! And I will recommend ur youtube to them in my reply!😊
I only had a Commodore 64 and a 1541 Disk Drive. I love all your Commodore videos. They bring back so many childhood memories.
Awesome video. It is funny how many people advocate using HD disks in place of DD. I have never been able to get them to work and wouldn't trust them if I did. Glad I found your channel, keep up the good work.
I did that with 3.5" disks a few times and it seemed to work but that wasn't for long-term storage. By the early 2000s DD floppies were pretty much impossible to find but some copy software required them for copying existing DD disks. In fact, it was probably easier to get your hands on NOS 5 1/4" HD floppies than on 3.5" DD ones, even though they were even more obsolete. I also briefly had an IBM PS/2, I think a Model 30, that only had a DD drive and I wanted to copy files. I also have a DD 3.5" floppy that someone punched a hole into and formatted it as HD eons ago, it worked. Don't know how long it worked and how the success rate would have been if you tried that with a bunch of floppies but this one worked.
Binge watching your videos. Great stuff! On this one, I have to say LOL, you told that whole story about the guy that claimed HD disks. worked for him and you said you didn't THINK he was lying, etc, but then you went on to show a drive YOU own that it works on. So you knew the whole time :) haha. Yeah, when I was a kid, I heard the same thing from one of my friends. I hadn't tried a HD disk myself but I remember a kid saying it worked for his friend but you still only got 664 blocks. I was bummed because I hoped you could somehow get even more storage. Of course, we know that would be impossible. The 1541 is still going to utilize the media in the same manner with the same number of sectors and only 256 bytes/sector.
Thank you! I couldn't figure out what was wrong. Awesome. I checked and the disks I was having trouble with were HD not DD. I tried with DD and it works! Thank YOU!
The HD disks seem a bit like the different types of audio-cassette tapes. Type I has a brown color while other types have darker colors and mixed-in cobalt and the writing is done differently for each type.
Interesting...this explains why I had issues with a couple of my disks back in the day. I think they were IBM branded. I managed to write to them ok but reading back was problematic. The fix was to open and close the drive door of the 1541 and then hold the door down with some pressure and most of time this would allow the game/data to load off the disk! Surprisingly this appeared not to damage the 1541 - the things we did when we were kids!
This is really interesting. I wonder if holding the door down with say an Alps mech drive resulted in the head sitting closer? I was one of those lucky ones that HD disks worked flawlessly, had an original pull down Alps model..
In high school, we had some of our computers in the same room with all the typewriters. I remember taking a 5.25" floppy and running through the typewriter and typing on the label... and it still worked! It looked like hell, and the sides were busting open from being cranked around that wheel, but it kept on reading and writing without a problem. Don't ask why I did it, because to this day I still don't know. :)
Thanks for your research. I just ordered some HD disks for my 64. Without your video I would probably pulling out my hair wondering what is wrong with my disks or the 1541. Thanks again. 🖖- Live long & prosper.
One thing I did many years ago when I encountered HD disks, was to use a strong magnet about 3 inches away from the disk on both sides. After doing that I think it would cancel out some of the peaks in the field placed there by an HD format on another machine. I could successfully write to the disks without any issue. I bet using a degauss coil would possibly work as well. Just wondering if anyone else has tried this.
Very interesting! I'd love to see someone make a video about experimenting with this approach!
I DID exactly that, but by software, today. facebook.com/groups/1548452001848020/permalink/4210985592261301
I did a bit similar in the MSX world, it is not that, the ring or the material, it is the original IBM formatted tracks, which are STEPED in different position are interfering with what you are trying to write, but IF you sweep with a good magnet all the original format, and the disk don't slide, IT must format and read OK, but, because always is a big "BUT", it won't LAST by years. IT is the difference in 80 tracks vs 40, So, if you are writing a wide track, the head can erase that part, but as originally is a pattern of 80 tracks, the TOO CLOSE to interfere next HD track will interfere.
Playing catch-up on your most recent videos. Informative video, yet again, Robin. Man, I always wanted a notcher -- I was always eyeballing them in the magazines when I was a kid. Wasn't that a movie, Godzilla Vs Mikadon? ;)
Thanks as always for your support! :) I think you're right about Mikadon being a movie monster. Crush Crumble and Chomp! anyone?
@@8_Bit LOL. Well said, sir, well said.
I didn‘t know about this. Would be intersting to scope the signal from the write head when readin DD and HD floppy disks. That might unveil a bit, maybe... gotta go to the basement and check...
IIRC, SD and DD disks were made from iron oxide (20kA/m coercive field strength), HD used cobalt-doped iron oxide (50kA/m coercive field strength). Thus, you would require twice the magnetic field strength to overwrite the disk, you might get away with a lower field when the magnetic layer has been demagnetized.
I remember going there and buying the same diskettes. I also went to Honest Ed's to get no name diskettes. Thanks for the memories
I cringed when you pressed down on your 1541 with the notcher, but it was "for science" so thank you sir.
I remember this shit. There was a variation of disk that could do both and that was one of the differences between expensive disks and cheaper or earlier disks. The brands that are around for later 3.5" floppies exist because of that feature.
The 1571 in the 128D is an example of the upgrade. Counting the tracks written is key, the drives that format a HD always format with the correct strength for the media. If it's still a 35 track disk format, the 1541 would probably read it.
I wouldn't try and write it with a 1541 after the fact. It would probably mess up the disk.
Back around the 2000s I wrote lots of Atari ST images to HD disks with the HD hole covered on a PC. Those disks worked fine on my ST back then, but none of those HD disks works now, 20 years later. But my DD disks still work like a charm even today.
Sorry for the zombie post... but I think the idea that some drives or disks are just enough beyond spec to barely maybe sort of kind of handle it is probably spot on.
One additional problem on high density vs double density 5.25" disks is the number of tracks is different. HD disk tracks are half the width of DD tracks, yielding twice as many tracks on HD than on DD, which is why it could be problematic to make a DD disk on a HD drive and try to use it in a DD drive.
I worked for several software companies that duplicated their own media and when we were creating masters for duplication, we had to be careful to make sure we created DD images on a true DD drive with true DD media. Any other combination led to QA issues and support calls.
The difference between 3.5" DD & HD is basically the same (the magnetic coating is different) but at least the track width was more or less the same (both had the same number of tracks but could write twice as many sectors per track in HD mode, so those sectors were 1/2 the physical size while holding the same amount of data).
Hi, found your channel I while ago, and just started to go through to watch all the videos on it.
re high density disks working in your C128D, i had a C128D back in the day too which I used for many years, and I had the same experience, HD disks would format perfectly fine (both sides) and even save stuff to them without issue, whereas a 1541 drive I obtained later on would not work with them at all.
Being that the C128D had a 1571 drive, it must be because of that, the 1571 is more tolerant or higher build quality, to have a better ability to use a wider range of disks or something. Which is why I would have liked to see you try on your external 1571 drive to see if the HD disks worked on that too (but you didn't use it in the video).
Even before I got my own 1541 though, I already knew about HD disks being totally unreliable when used as a DD disk, so I never used them anyway, and on the occasion someone else sent me stuff on a HD disk (it did happen) I immediately copied it to a blank DD disk in my 128D before loading the stuff contained on it.
Utility cartridges are nice too. I had an Action Replay back in the day, with many similar features to the Super Snapshot (just accessed and used in slightly different ways). Love the fast format the AR offered, formatted disks in just 10 seconds, no messing around waiting for it to finish there.
The ring that you see on the DSDD was a reinforcement ring. Also did you try to format it on the 1571 that was below the 1541? The 128D has a 1571 built in.
Similar experience here with HD disks. My dad brought home a number of used 5.25" disks for me to use on my C64. I found they wouldn't format on my 1541 -- BUT after rubbing them on a rather strong magnet, quite often they would work! I wound up using them for years, but they were unreliable in the sense that if you wrote to them there was a chance of corruption. However, once data was written successfully I never had trouble reading it back, even 30 years later. My theory as a 12-year-old was that the magnetic field on the disks needed to be "reset" for them to work on the 1541. After making this discovery, I began using the magnet as a bulk disk eraser. This eventually cost me a brand new copy of Test Drive, when my little brother took the game disk out of the drive and decided the magnet looked like a perfect place to store it.
Very interesting story (sorry about the Test Drive though!). It'd be very interesting to find out why the magnet would increase the chance of successfully writing to the disk. Like you were saying about the magnet doing a "reset", maybe it would put the magnetic surface in a more neutral position that the weaker 1541 write head could affect easier?
@@8_Bit Fortunately I was able to exchange my copy of Test Drive at Toys 'R' Us. Yes, I suppose it put the surface into a more neutral state, as you say. It would be interesting to know the science behind why that (kind of) worked. Here's an example of the magnet I was using: www.giftsforprofessionals.com/category/magnetic-desk-toys
High density drives write a much stronger signal onto the disks using a magnet wipes the disk allowing you to start fresh
I've run into this issue too and just thought I had some bad disks. And now we know the rest of the story...
I just got my first ever 1541! Unfortunately it did not come with the serial cable, so I need to find one of those. But I'm excited to finally have disk access for my VIC-20!
Speaking of which, I STILL haven't been able to get any more disks for it. Luckily it came with one, but I want spares! And I need to get my C64 working or trade it for a working one or something.
I absolutely agree. I recently bought a mix of different floppies on eBay. All the 2D floppies formatted in my 1571. None of the HD ones did.
I'm impressed with how well this media holds up. For some reason (perhaps it was just too soon) I never came in contact with the HD disks for my c64. Luckily I never had a problem reading disks because of their density. Having seen your video, I know I never will.
I got an svideo cable for the Commodore 64 and was playing Ghostbusters on my hd tv. It looked surprising good on it, and the disk was the same disk from my childhood.
@@tazgamerplays Great isn't it? When I played Ghostbusters again (for the first time in decades) I figured out that I had to press 'B' to get the marshmallow man to not destroy the buildings.
@@TheHighlander71 I really enjoyed the game, I even have the retail box and disk now. Oh and B only works if you buy the ghost bait, and there is an account number you can put in at the beginning to get tons of money.
@@tazgamerplays I always wondered why I could enter an account number at the start of the game. Now that I've ended the game with enough money, I finally get it. This is why manuals are important :)
@@TheHighlander71 I only ever beat the game once. I always had trouble at getting 2 characters past the Marshmallow Man.
My 1541 would occasionally eat hub rings. I don't know what kind of material that stuff was, but man, you pretty much needed scissors to get it out. Some tough plastic.
I can't remember if I ever had success with HD disks or not. I know I had encountered them, but can't recall if they ever worked for me.
They probably never worked.
This is interesting, I didn't know there was a difference between the drive heads on the 1541 and 1571/1571CR (barring the fact the 1571 has dual heads, of course).
I don't recall you addressing it in this video - since HD disks appear to work in the 1571CR (the one inside your 128D), did you try handling them in the standalone 1571 as well?
Interestingly, the HD floppies didn't format in the standalone 1571. The video was going fairly long already so I decided to just show one that worked and one that didn't, but maybe I'll do a follow-up video with the 1571, 1541-II and possibly other drives. Maybe I should even do a couple of each model as perhaps it's not even consistent within a model?
My guess is that the 1541, being released in 1982 or so, all drive mechanisms commonly available were DD mechanisms, as the IBM PC AT with HD 5.25" drives hadn't yet been released. By the time the 1571 and later the C128D were released, PC AT was on the market and more and more DD drives were probably available that shared traits with their HD cousins. The given that C128D came out a year or more after the C128 + 1571 were released (more or less) it kind of makes some sort of sense to me that drives were "friendlier" (though not really intended to be mixed like that).
Embassy Gold! Awesomes memories! 1-3 disks per box failed in the first 3 months of use. All I could afford at the time.
I remember getting it in multi colour packs.
Wabash was the plague in our local 99/4a community. They worked fine at first, then at some point in the (probably near) future decided to drag against the disk head. End result: Two concentric circles devoid of magnetic media, missing data, and a drive that desperately needs cleaning.
Several years ago when a Radio Shack in the area was closing down, I went there and bought them out of 5.25" floppies which I was surprised they still had. I got a ton of them for maybe $5. But it wasn't until after I got them home that I discovered they were all HD, and HD floppies aren't compatible with the 1541! I was so disappointed. I still have them and don't know what to do with them. BTW, I love Fast Hack'em format: 9 seconds and done. JiffyDOS is pretty fast, too.
Yes, I don't know what to do with my huge box of HD 5.25" floppies I got on clearance either. Well, I did format a few on my Commodore PC 50-II computer. But I've got hundreds more :)
I have some of these hd disks. WOrked fine. A few with ekstra ring around hole like the dd.
On some of the dd it says hardhole and sector soft. What is that?
Intresting video. 👍 On my Enhancer 2000 disc drive HD floppys seems work fine, even after 20 years!
It'd be interesting to do a run-down on all the different 5.25" drives available for the C64 and see which ones work with HD disks. It may even vary within the same model, especially the 1541 since so many were produced.
@@8_Bit Yes that would be interesting as most people probably only have one disc drive.
I don't know if this is a rare one, but I still have one of those: www.c64-wiki.com/wiki/OC-118N
Interesting! I have a 1541 too, and I have some imation DS, HD disks, that format normally and are usable...
The reason why the HD floppy disks required a higher magnetic flux was so that they could support the higher density of data.
If you try to "squash" data bits too close together on a disk, the magnetic field used to write the bits will tend to "spill over" to adjacent bits, possibly overwriting them.
When the magnetic coating won't take the data as easily, then the bits can be placed closer together without the magnetic field from the write head adversely affecting nearby bits, even though the magnetic field needs to be stronger to write each bit.
Hi, I got a question: I bought a c64 used and got a big stack of flopys free. They are supposed to be emoty, but some still contain data. On most of the disks my comodore frezes loading with the 1541-2 doing nothing. Could it be bit rott from questionable storage conditions?
Lucky you finding 50 boxes of DSHD Diskettes... Need some myself for my AT
I`m C128 owner. Someday i bought Polaroid`s DataRescue diskettes 2S/4D (Quad Density) 96TPI. Never had any issues with formating or writing/reading. My disk drive is a liitle difrent than yours, with Alps drive mechanism. BTW one of my 10 diskette pack still folied...
This is the first time I've heard about this. Back in 1995 or so, when I was still regularly using a C64, I bought a couple boxes of 5.25" disks, which were still readily available. They were ordinary 3M brand if I recall, and IBM formatted, but not sure if they were HD but assume they were (they're in storage) or if DD were still even regularly sold anymore at the time. I never had trouble with any of them, this with using a 1571, and saved quite a bit of stuff back then but have barely touched them since the late '90s and not all since 2004 or so. What I'm concerned with now is, assuming they're HD, if the recordings are still viable, assuming they weren't adequately magnetized back then.
back in the day i used to have some dshd diskettes too... i've had games on some of them and i couldn't read or write them with most of my drives, only my 1571 could decently write and read from the ones thta worked (and most of them didnt). I had 4 drives and copied tons of diskettes (literally thousands) one time i had a batch of hd disks used, and the guy who bought those disks from me couldn't read them at all. Since then i banned ALL hd diskettes, i even lost some data as some diskettes i had couldn't be read anymore, not even with the 1571. (my collection was over 2000 diskettes). In case you're wondering, i used the superdisk toolkit to copy all of my disks as it could copy from one to multiple drives at high speed
One thing to note is that commodore never produced the actual disk drives. The drives were made by alps, then mitzumi...but after that it might have been made by teac or some of the more modern manufactuerers. This would mean that the drives being manufactured would likely end up in a wide range of machines. Its just possible that the newer drives were meant to handle both DD AND HD. Just as youd find in an IBM or compatible AT.
Nobody:
Basic: "AAAAAAAAAAAAAAAAAAAAAAAA"
I think his computer is channeling Henry Winkler as the fonz
After formatting with the 1571 or copying a DSDD disk to a DSHD, can you read that disk in the 1541?
I haven't thoroughly tested this, but it seems that if the 1571 successfully writes to the DSHD floppy then a 1541 will be able to read it too. But not all 1571s can write to all HD disks.
Your pronunciation of 'ørsted' is quite fine for a non-Danish speaker, don't worry.
Jep agreed.
The hub ring is not the problem. It's used to strengthen the media at the center so it doesn't slip or tear easily. The real problem is the magnetic coercivity of the media itself. Commodore drives are only designed to recognize and work with DSDD Diskettes. IBM PC and compatibles could do both because the mechanism itself compensates with the extra tracks and different coercivity. When you format a 1.2M Diskette as 360K, the drive just uses less tracks. The coercivity is automatically adjusted.
Edit: oh you said this in the video
I don't recall ever having this issue with my CoCo2 and its drive. I had a PC with 1.2Mb floppy and the disks seemed interchangeable. Am I imagining this? Is this only a C64 drive peculiarity?
I wonder if you could simply bump up the write power of the drive to around 400 or 450 and start to get reliable reads on both?
I don't know how you'd increase the write power of the head (if it could take it even). But it was not a C64 drive peculiarity. You could not reliably format or use HD media in a DD drive on an IBM PC or IBM PC XT. The specs were just too low for the magnetic field to make a difference.
Hi Robin, I am a fellow French Canadian from Montreal region. Your videos are part of the reason I jumped into the retro 64 adventure my self. I recently found my self a functional 1541 disk drive and I was wondering if You knew where I could find new DD floppy disks, either on the web or among yours subscribers. Thanks for your videos and knowledge sharing. Best regards.
Hi Daniel! I haven't bought any yet, so don't consider this a recommendation, but this place sells them bulk, $50 USD for 50. You have to buy the sleeves separately: www.floppydisk.com/5point25
I think there's another place selling them bulk also, but haven't found any good Canadian source unfortunately.
Hi Robin, I have bought a bunch of floppies from the site you have suggested me. I could not find any other place where I could buy some. I ordered a 50 unformatted pack plus a 50 pack sleeve pack. It cost me $112.00 CDN. I have receive them and formatted/copied a bunch of them. Everything seems to be fine. I copied disk and files from my 1541 Ultimate II+, using the 1541 demo disk and other cassette utilities. The 1541 drive à found is working like a charm. So big thanks for pointing this site to me. The adventure continues. Best regards.
P.s. I had to make the second write protect hole using cutters and an exacto. Ha the good old days. Bye again.
@@roaddan01 That seems like very fast shipping from the USA! I'm glad it worked out well, maybe I will buy 50 there myself soon. Thanks for the update.
In the early 90ies some compatible (but not original) floppy drives appeared. They had a standard PC floppy drive and a microcontroller emulating the 1541 behaviour. They´ve been much cheaper than the originals.
Probably these could handle HD disks. I had one of these and it worked.
I remember reformatting HD floppies on the ZX spectrum. I dont remember how well they worked, but as I dont remember issues either, I think they were fine :)
If you want check my program to test 1541 speed: github.com/Zibri/C64-1541-Speed-Test I just released it a few days ago.
I would like to tell you few things about the C1541 drive and the DD/HD disks problems.
TL;DR: C1541 is weak and cannot overwrite the PC formatted disk.
Long story:
Hub ring - missing hub ring could, in some conditions, make the drive some problems when trying to spin the disk. But it is not the difference of the DD over the HD disk.
Feromagnetic coating - this could be one of the sides of the main problem, but usually the HD disks are made of finer material than those DD ones. The coercivity could be just a part of the issue.
The C1541 drive heads - this is what goes on in that case. The main problem is the output current for the writing head. On the PC the writing currents are higher, making the material magnetized deeper. And the C1541 drive is not powerful enough to revert the magnetization of the cells in the magnetic coating of the media. If there is no magnetization, it is strong enough to make it magnetized to some level. But the level used in PC drive is higher.
You should know, that those HD disk usually came "preformatted" for the IBM PC standard!
So if you would like to use those HD disks with your C1541 drives, be sure to have them "demagnetized" first. The best way is usually to use "the media cleaner", used in production companies/TV station productions, to clean their BETA tapes and so on. It has to use the "hi-frequency" electromagnetic field.
Of course the C1571 drive is newer, advanced and uses stronger currents. The C128D uses this C1571 drive internally. So that's why the C128D was able to format the disk.
Holy cow! I worked at Mikadon (County Fair) for a while when I was 14 --up until it folded (don't blame me!).
Missed the days when that was *the* store to get Amiga stuff...
Awesome! You probably worked with my friend Darren then?
@@8_Bit Darren sounds familiar, but to be honest, those memories are pretty faded these days.
I do remember the delivery guy who was the king of winning mail-in contests, selling Ambras, returning Ambras, and the great Saskatchewan Wheat Pool PC fiasco tho!
@@idarkpuppet That was Doug! Still run into him once in a while.
Oh man, that's so cool -- I hope he's doing well. Loved talking to him when he made his rounds.
This is fun. Hope your channel is doing well -- it's great listening while at work..
I'll have to schedule my next visit to TBay around your retro club schedule. :P
Holy shi--- I remember going to that store ages ago. The name sounded familiar. There is video here on youtube.
watch?v=ikRcKfT_ur8
HD floppies do not work in a DD drive because the properties of the magnetic material are different. The amount of energy required to write and read HD disks is different than DD disks and the data rate used to write the disk is also different. also the track width of a HD disk is narrower than for DD disks. Some single sided double density disks will not work when the disk is flipped. This happened in the early days because it was too expensive to test and format the second side. Later, the quality of DD floppies was much better and the same media was used for single sided floppies. This allowed floppies to be flipped.
I am curious if in 128 mode, the high density disk gets the 1328 blocks.
Oddly, my 128D always formats just one side of my DD disks, even in 128 mode using the HEADER command. I have to put in a sort-of cryptic command to force to format both sides. It could be the custom JiffyDOS that the seller installed on it or if all 128D machines do that.
If the 128 manages to successfully format the high density disk while in double-sided mode then yes, it'll get 1328 blocks free. It's really hit and miss. It's probably the JiffyDOS in your machine forcing the internal drive to single-side mode, if it's happening when you power up directly into 128 mode.
Do PET or radio shack use them? SDF1000?
My Clone Oceanic Drive seems to be quite happy reading and formatting HD Disks, perhaps they are using 1570/1571 or similar mutiple format capable drives
HD also didn't work on the Amiga, if you had no modified PC drive ... was so bad and sad
one said, he swapped the drive from a 541 to a pc hardware drive, but I can't believe it - because the electronik is for a DD disk
somehow like with audio tapes (ferro and chrome / metal)
The inner ring hub was quality, some disk makers added them some did not.
any idea where to buy DSDD disks NEW for commodore or Atari these days?
There's a couple websites offering them for about $1 each when you buy them in quantity:
www.tindie.com/products/glitchwrks/lot-of-10-nos-athana-dsdd-360k-525-floppy-disks/
www.floppydisk.com/5point25
I found out that the 1541C (Mitsumi drive) has problems with HD Disks, but the 1541 II (Chinon drive) and the 1571 can handle HD disks, i even could backup original copyprotected disks and they work. The brand i use is "db boeder". Maybe i was just lucky to have good working disk drives.
What about the shutter on the drive.The drive with a flap is a different sort.Alps and newtronic and there's a jumper on the board for the different drives,you can swap them but you need to look at the jumper setting.I think the jumper j6 is to do with the current to the read write head.J6.
This gives me a few thoughts:
1) If you save data to a HD disk in DD format on a drive that can write correctly, I assume you can read that data on a drive that can only read DD disks. In this case, you could use it as a sort of "read only" disk. You can't accidently erase your data without deliberately moving back to the drive that can write to HD disks.
2) Imagine a proprietary formula of disk for commercial software (even higher coercivity than HD disks so that NO normal drive can write to them). You write the disk with a custom drive that can write with stronger magnetic fields, then sell the disk to customers. Customers can't erase your disk because their drive can't write. SO...first thing you try to do when starting the software up after loading is write to overwrite your software. If the disk has been pirated...OOPS! the disk is now blank. If the disk is too high coercivity (authentic), then you can't write anyway, so the software runs and doesn't self destruct.
3) Different regions of the disk surface could be different chemistry. You can have regions that you can't write to, like game code and resource files, and regions you can write to, such as save game data.
4) You can modify the disk drive to increase the current going to the write head (or replace the head with a higher power one), thus enabling you to safely and reliably write to HD disks (and with proper signal strength that doesn't degrade and become unreadable after a while).
5) In theory, a higher temperature medium will have a lower coercivity. How high in temperature can you drive go before it becomes damaged? Can you heat up the disk drive (and the disk inside it) somehow and make it able to write to the disk? I imagine any temp high enough to sufficiently weaken the magnetic coercivity of the disk would be very close to the curie point (where magnetic materials break down and lose their magnetic properties). This would certainly destroy the motors in your drive, and probably cook the electronics to death too. I guess this idea is terrible.
Interesting ideas, I wonder if anyone's ever experimented with these!
And i reccomend, always before hit RETURN close command, i mean write all full command with OPEN and CLOSE, and after each format try to Initialize each disk, best regards.
an old school disk. Do you know the double density can convert to high density floppy disk you must remove the tape at the middle of the circle but it makes badsector if you format from 360kb to 1mb disk
Happened to me as well. I used the HD disks to watch the 1999 Total Eclipse with them.
...despite all the warnings against doing that.
I hope your vision did not get impaired?
I got a disk drive recently and I can't format any of my disk. and I don't know what to do..... I use DD disk. the drive start format like 3 sector. a'd after the delay betwen sector are long. and at the end I got a error. a'd I got a vic-20 not à C64..... I cleaned the head. to a'd nothing.
Atari worked with my HD diskettes in DD drive. But there was an issue - they was not read on second DD-drive, and vice versa.
I have Commodore 128D too, and put it into C64 mode and tried to format it using the 1571's 1541 mode and it still would not work with HD disks, and neither worked in C128/1571 mode also... oh well...
So my dad was going through my old computer room at his place, and my C-64 was still there. He brought it down, and I started looking at my notes that were with some of the boxes of programs I have. For my windows 5 1/4 disks, HD i typed
OPEN 1,8,15 "N:DISK16,1A":CLOSE 1
and formatted then it read 664 block free. Could these still fail?
OPEN (space bar) 1,8,15 (space bar) "N:DISK16,1A":CLOSE (space bar) 1
Then LOAD. "$",8
Then LIST
AND IT READS AS FOLLOWS
0 "DISK16 ",1A 2A
664 BLOCKS FREE.
READY.
Nice that you are using your old C64 again! Generally I've found HD disks are very unreliable; even if you manage to format one you will probably run into trouble saving to it, and over time it will lose data. But it really does seem to vary depending on the disks and the drive; maybe yours will be fine.
Thank you, maybe I will use the HD as a last resort, I bought and have be storing 200 brand new C64 format style DDSS, but have so many of the mix, of some DDSS and HD ones, all open and used except for about 24 of them. My college son does programming and wanted to use it to play with so thats why I was wondering. Again thank you !!!!
The reason why the HD disks have a coating that requires stronger magnetic fields is because the tracks are closer together. So when one track is written to, it must be ensured that the tracks next to it are not also written to. By making the coating less sensitive to magnetic fields, a strong magnetic field writing to one track will already be too weak to write to the adjacent tracks. This is not a problem with DD disks because the tracks are further apart and the magnetic field decreases greatly with distance.
An alternative would have been to make the coating even more sensitive and simply work with weaker magnetic fields, but this approach would have had the disadvantage that the disks would then become much more sensitive to magnetic fields from external sources, and magnetic fields always occur around a computer and TV, even every power supply generates some.
There were about 4 versions of the 1541, and these were not marked, so some of the later ones may have had different mechanisms then the early ones... The fact the drives were "smart" meant that a change of mechanism could be accomodated with a change in the ROMS.
Ok 1541 does not work with HD disks and 128d drive does. But does anybody tests 1541-II or 1571 ?
I wouldn't expect the reverse side of any single sided disk to work (at 10:20) because the pilot hole is now on the wrong side, thus it would not be able to detect rotational speed. I remember having some double sided disks for the BBC Micro (they were actually double sided as you could flip them over) and they had 2 pilot holes either side of the main spindle hole. The notch(es) on the side(s) are used to control if the disk is writable or not for that side, similar to the notches on audio cassette tapes.
only certain drives/computers required that hole... AFAIK the Commodore drives don't.
PLEASE RECAP your Monitor or cut it off while talking!!!! I'm 51 years old and can still hear that CRT Squeal!!! Love The Videos!
Sorry, I think this is the only video I've made that I forgot to filter out the CRT whine. Let me know if you hear it in any of the others, but I think I got it. Still hearing it at 51 is impressive!
why didnt you try using the external 1571 disk drive to format the HD disk? perhaps you can try doing so and show results?
I gave the external 1571 a try and it failed to format the disk, just like the 1541. Then I discovered the internal 1571 in the 128D worked, and left it at that as the video was already getting so long. Originally I was going to use my Commodore PC-50 II computer, with internal HD 5.25" floppy drive to prove the HD disks would format okay, but it became unnecessary also.
But yeah, I might revisit this in the future with more drives from my collection.
Didn't the C= 128D have a 1571 diskdrive? Wasn't the 1571 drive HD capable (in 128 mode)?
Nope, it was IBM PC MFM format compatible, but it's capacity was still only 360KB, and required DD discs.
Zoltan Markus Ah, I see… Well, I’ve only ever had the C64-C with its 1541-II drive and the ubiquitous Datasette, so I really didn’t know much about the 128, unfortunately…
When I started shipping Loadstar, I got a good deal with HD 3.5 disks. Never had a problem since I used an FD drive - or PC > 1581 copy (on the PC). But immediately got many who used real 1581s writing to me. Didn't work! Had to go to DD 3.5s for them.
Ugh, that must have been painful and costly to correct!
The reason why the 1541 failed to format the high density disk is not because the disk is bad, but because the 1541 wasn't designed to deal with such disks. High density disks were meant to be formatted in IBM compatible systems that had 5.25" floppy drives that supported those disks. Also, they spin at 360 rpm, and they need a much stronger magnetic field to write to them and were often pre-formatted. The manual for 1541 states that only double density disks should be used. The rotational speed is 300 rpm. Formatting a disk takes 80 seconds which is slow compared to other drives. The rattling sound you hear when you format a disk is the head being banged against the stop. The reason for this is that the drive has no way of knowing where Track 0 is located, which is why it does that. It also does that when it encounters an error and can be caused by disk protection.
Can the 1541 read HD floppies even though it can't format them?
we have to make a fix for the 1541 :-)
a kind of calibration run when formating would be cool and writing the power information on a reserved space if there is one.
if there is no reserved space available, then the drive would have to make a check after each new write
I just did :D facebook.com/groups/1548452001848020/permalink/4210985592261301
I believe it is because high density floppy need a higher bias due to the difference in magnetic material composition.
Similarly to not being able to record on a chrome audio tape with a cheap tape recorder.
I was pondering a few years ago (I have a lot of 5.25" HD diskettes) whether could be possible to design an interface that could allow to connect HD floppy disk drive to C-64. Someone created interface to SanDisk cards anyway, so it's feasible as well. Just we need detailed docs describing functionality of old FDD controller for IBM-AT.
It'd be cool to have a 5.25" HD drive for the C64. CMD made the FD-2000 drive which uses 3.5" HD disks. Each one stores 1.6 MB, which is pretty nice. But I don't think anyone ever made the equivalent 5.25" drive.
@@8_Bit To find more information seems to be difficult - for example: first question is do we want such interface to be placed in between FDD and C-64 - or it'll be better to keep IBM-AT's FDD-controller as well? Honestly, at this moment no idea.
Some leads that could be found: www.oldskool.org/disk2fdi/525HDMOD.htm
I had plenty of HD-disks for my C64 and 1541 back in the early 90s and I never thought about it because it never troubled me.
And after 30 years, these diskettes still work fine. How can that be? :D
However, half a year ago I discovered that I wasn't able to format new HD-discs so I googled it and found out that they shouldn't work.
Although now again they all work fine. Very strange!
I wonder why that 1541 has a square led... I remember it round like the power led.
You're probably thinking of the 1541 drives with an Alps drive mechanism, which had a round LED. There were also many 1541 produced with Newtronics mechs, which have a more rectangular drive LED.
I've used HD disks on my C64 without any issue but I wrote them with a PC using a parallel port cable I made, dont know if that would make any difference or if I was just lucky, I'll have a look later to see if they have the ring or not.
As far as I know it wouldn't have anything to do with the cable. What model of drive is it, a typical 1541?
@@8_Bit Its a 1541-II and the disks I wrote are just for some demoscene demos, so haven't been re-written by the C64
have the same isue, back in 1990, wen i bougth a floppy disck, and dont work on my 1541 drive, but find a way around to makeit work, letme take out my drive to show you, how i fix it..
I had similar experiences with my Amiga. Over the hears, I had 4 Amigas, and multiple external drives. Some would read and write to HD disks without an issue. Some would only read, and some didn't touch them at all. It was a bit of a nightmare. Back to the c64, I don't think the plastic hub guard made much of a difference, as you know the reverse of the disks don't have them, and you can still use the 2nd side of the disk fine.
I bought an Amiga 500 in late 1990. (UK model). In 1992 i bought 200 floppy disks in Wien but they accidentally gave HD disks for the price of the DD disks. I only noticed it when we came back to Hungary. They were the cheapest disks available on the market. My Amiga had no problem reading and writing em, and almost none of em had any bad sectors. 2 years later i bought a PC and i formatted em all to HD. They were working ofc but some of em had bad sectors. Just to mention: my only "marketed" brand disks for the Amiga were 10 pieces of 3M DD diskettes. I used em for years, THEN i formatted em to HD on the PC (had to make a hole on their other side for it) and they were worked flawlessly! They are still readable to this day. Not bad from some 33 years old diskettes!
As new DD diskettes are getting harder and harder (and expensive) to find here in Hungary, I'm planning to do a mod on my 1541, to make it able to save on HD disks. I'll put a switch on it somewhere, which will adjust the recording current to match the different formulation. Reading the disks saved on this modded drive with other 1541 should be fine, only saving to them is a problem. I'll probably put a reed switch behind the case, somewhere far away from the disk, and this way I will be able to switch between modes by putting a strong external magnet to the right spot. I don't like the idea of drilling holes for mod switches on my 1541. There might be a fatal trap for this plan: if the head can't handle the doubled recording current, and saturates. I *probably* won't go so far to transplant a HD capable drive's head into my 1541...
What's the memory difference of DD and HD? They all should be 180kb per side yes?
The classic C= 8-bit drives like the 1541 and 1571 format to 170K per side, and if they manage to format a HD floppy, it will also have 170K per side.
@@8_Bit Thank you for your answer. Ever get the rare 1581 3.5 commodore drive? Also musicians still use these 5.25 disks for their emu sp12 or turbo machines midi to 1541 drive.
Yes, I have a 1581, and in fact I have the even rarer CMD FD-2000 which is a high density 3.5" drive for Commodore. 1.6 MB per 3.5" disk!
@@8_Bit 4 Questions
*1* Awesome that is the 2.28 mb memory rare 3.5 floppy, not just 1.44 mb memory 3.5 size then correct Supposedly Google says there were 1.4 and 2.28 size 3.5 floppies.
*2* Would you be able to locate , another 1581, in your travels? I will gladly pay you.
*3* The 5.25 are kilobits not kilobytes yes? And 3.5 are megabytes not megabits? Or, hope I got that right, can you type out how much 8 inch 5.25 inch C64 cassette and 3.5 inch in terms of bits or bytes or megas or total memory - I'm confused lol. Maybe cassette held more data?
*4* What is name of round serial port on back of my 1541 a midi or 9 pin connector what's official name of it? Because I'm looking for a midi or w/e to USB cable so I can save game "sound" data to my PC program as back up =)
Hm.. I didnt pay attention to my disks when using my Commodore 1541.. not sure if it was DD or HD... alas.. most of the disks worked for me, not sure which types, maybe they were DD.
Tryed this on my 128d back in the day. HD disks were a no go for it
Die alten Computer hören sich wie ein Elektro Schreibmaschine
Tasten einschlag der buchstaben drucken erfolgt von unten mit hilfe des Magneten besser gesagt alles umgekehrt von der schreibmaschine
Wonder what mods would need to be done to switch it out for a 1.2M HD drive and run an upgraded drive.
you would need a new DOS, different drive interface electronics, minimum. You'd be basically engineering a whole new drive :P
Did you try it in the 1571 drive?
😂 Bargain Harold's this guy is definitely Canadian
this rattling of the head hurts again and again ...
back in the days no one tok this seriously, but today we know, it is bad :D
I use HD Disks in my 1571 for ober 20 years, without issue.
Also I have no issue with HD Disks on my 1581. But I havent testet this for so long. I got it for 2 years now.
Interesting. I own a C128 with 1541 and 1571, I'm pondering to try it myself. Here's an idea. Put one of those HD floppies in an old regular PC and format it with the parameter for 360k or 720k, and see what happens. Then try to format again on the 1541....
By the way: I have the exact same floppy puncher as you do, over here in Europe!
I just used a pair of scissors to punch a write tab no the opposite side of a disk - worked every time
won't work. The 1541 had a proprietary format.
It has to do with the magnetic coercivity of the media itself. The reason a PC drive can write a 1.2M Diskette as 360K is because the mechanism can detect the media type and adjust for it. The commodore drives can't do that.
Edit: oh he mentioned this in the video
@@AiOinc1 the 1541 drive can in fact do it, but you have to run a program that reprograms the drive. The 1541 has an entire computer on board and can read any 5 1/4 format as long as you program it properly.
@@LordOrwell Are you sure? I don't think the 1541 has ablity to adjust the recording current and bias by software. It's done in hardware, as it's only designed to be used with one specific media type.
Squeeze the puncher within your hand, much easier that trying to push it down on a flexible housing...
Using my 1541 as the punching surface wasn't the smartest thing I have done. :) Though using my hand wouldn't be too smart either, as the puncher pokes out the bottom slightly...
We had the same or similar one, wasn't really a problem with my right hand, you feel the hole and space your fingers around it. I might even hit my fingers once or twice with the cutter, but never got a cut. (so far as I can remember at least)
Well he did 'hammer it home', and that was painful viewing indeed. First he stamps the notch ON the delicate floppy drive, then he does it again, sending a shock wave through the 1541 drive, whilst it's formatting a disk/disc! 😂 🖋