SpidersWeb
Veteran Member
They were sold to him as "DD 96tpi" but unbranded - there was a thread a while back. I was a bit dubious that they could actually be HD, but they seem to be working fine.
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720Kb 5.25" floppys
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Yes they work fine and do not failing to read at any time while using them as you should do, and formats perfectly as 360k floppies.
krebizfan
Veteran Member
I could be wrong but I thought many later 48 tpi diskettes were manufactured with the same cookies as the 96 tpi diskettes.
To truly have fun with 96 tpi diskettes, get a DEC RX-50 which has two single sided quad density drives inside one mounting. 400 kB per side, 2 floppies inside, and both floppies could be manually flipped for a total of 1.6 MB.
To truly have fun with 96 tpi diskettes, get a DEC RX-50 which has two single sided quad density drives inside one mounting. 400 kB per side, 2 floppies inside, and both floppies could be manually flipped for a total of 1.6 MB.
Chuck(G)
25k Member
Yup. I got it straight from Dysan tech support way back when. Supposedly the 96 tpi cookies are verified at 96 tpi rather than 48, but that only applies to pre-formatted floppies. Same goes for 100 tpi floppies.
SomeGuy
Veteran Member
What is happening here is that the tracks on a 5.25" floppy disk for each side are not right on top of each other. The second head is a little further back. If you format a flippy disk as double-sided, flip it over and format the other side, the first track on the first side is not overwritten. But everything else *IS*.
Under DOS this makes the disk look like it is still formatted until you try to read anything from it.
The 96TPI rating is not really relevant here. What that means (assuming this is not high density) is if you had used a 1.2mb drive or an "oddball" 96TPI low density drive, it should reliably format using 80 thinner tracks instead of 40. That would give you a total amount of storage around 720k. But again, that would already be using both sides, so you couldn't use it a as "flippy". (technically you could indeed format a flippy as 80 tracks, 9 sectors, single sided in a 1.2mb drive for 360k on each side, but that would be weird.)
Under DOS this makes the disk look like it is still formatted until you try to read anything from it.
The 96TPI rating is not really relevant here. What that means (assuming this is not high density) is if you had used a 1.2mb drive or an "oddball" 96TPI low density drive, it should reliably format using 80 thinner tracks instead of 40. That would give you a total amount of storage around 720k. But again, that would already be using both sides, so you couldn't use it a as "flippy". (technically you could indeed format a flippy as 80 tracks, 9 sectors, single sided in a 1.2mb drive for 360k on each side, but that would be weird.)
Since i dont want to make a new thread, is asking here, i use a HDD for booting and store files. These HDDs will not last forever(even if they have survived like 4-5 generation of HDDs already) and will some day crash, and they will get harder and harder to get and some day all consumed, same will happen with the old floppies we use. What then?
Todays HDDs last like 5 to max 10 years, mine have last around 30 years!
EDIT: @SomeGuy: Your explanation about the tracks make it all clear for me, now i understand why it acts like this, thanks for the input!
Todays HDDs last like 5 to max 10 years, mine have last around 30 years!
EDIT: @SomeGuy: Your explanation about the tracks make it all clear for me, now i understand why it acts like this, thanks for the input!
Stone
10k Member
Hey, I've got a nice bridge for sale -- wanna buy it?
SpidersWeb
Veteran Member
SpidersWeb
Veteran Member
Well you don't want to build one right now but that's where the future is.
I found with SMD kits, solder paste and running a soldering iron down the pins works a treat. Actually pretty cool watching blue paste magically turn in to shiny solder and grab on!
but that's where the future is. I found with SMD kits, solder paste and running a soldering iron down the pins works a treat. Actually pretty cool watching blue paste magically turn in to shiny solder and grab on!
Chuck(G)
25k Member
The originals were through-hole versions and considerably easier to assemble. Are there any more of those around?
carlsson
Veteran Member
Somewhere I've got two original XT-IDE's. I assembled them with a kit of parts, but I didn't get either to work. The first one booted up but would not detect any hard drive, the second one didn't even result in a boot message. I am fully confident it is due to poor soldering job from my side, but I haven't put any effort in trouble shooting those. The one that boots but doesn't detect drives might be the easier to fix.
Retro System Interface to Modern Peripherals:
Retro System Interface to Modern Peripherals:
PC HDD ANSWER:
For early PCs, the system needs a retro interface to SATA drives. SATA can be used in a default IDE protocol which really simplifies things. Just a matter of designing an IDE board for early PCs with an intelligent controller to make peace between the two sides. You won't get all the speed advantages of SATA because an intelligent controller will have to buffer and spoon-feed the early PC. Note you likely won't be able to access the complete modern SATA drive's capacity, but you could expand the amount used with a logical drive mapping such as C:,D:... Z:. While we might not be able to use that much data storage, its offensive not to be able to access everything you've bought. Solution, SATA logical banking to reuse some of the C:-Z: drive names.
CP/M HDD ANSWER:
HDD for non-PC systems: An interface to SATA drives can be designed for the CP/M era but you won't be able to access Terabytes of storage through a 64K page; it might take you a week to key in all the multiples of remapped drive names. You won't get all the speed advantages of SATA because an intelligent controller will have to buffer and spoon-feed the CP/M system.
My thinking is to make such a SATA drive a shared external so that can improve the use of the drive by allowing your other non-PC systems access it via an external shared comm link like cheaper RS-422/485; not RS422 direct... hiddon on the other side of the fake-floppy drive (concept similar to a storage drive on ethernet). The advantage here is if you have three systems, you don't have to buy 3 SATA drives (no one is that dedicated to CP/M). As these CP/M systems are all so unique, my solution is to go for the common high-speed interface, the floppy cable. A floppy emulator (I prefer the less pretentious term "Fake Floppy" drive) is really the ideal way to tap into non PC, CP/M era computers. But forget that floppy counter interface (that's poorly thought out). Technically you can hang anything on the other side of a fake-floppy (including universal Floppy reading drives). SCSI interfacers won't like that but the floppy interface serves the greater community... maybe SCSI and more unique solutions could be a later variant.
CP/M FLOPPY ANSWER:
This typically requires something (1) to read old floppies, recovering everything possible (instead of PASS/FAIL), (2) to store images on modern computers for storage on HDD/DVD/CD/USB/CF, (3) to recreate a new floppy in any format to use or store, (4) to read useful transportable media like CF/USB.Mem/uSD/ as if it were your boot floppy, (5) maintain a RomDrive on your floppy cable to access you entire collection of floppy disks (why wear-out your floppies). Note that a cost effective NAND Flash rom, 1GBYTE (bytewide) single chip is ~$6 in production but it takes an intelligent controller to better access it, hence a fake floppy solution.
Thats more easy than it sounds: That means you can store all the information from your old floppies in one small solid state card.
To read floppies universally, I hear there are several groups addressing this various ways. I decided to do my own as a fake floppy that emulates a floppy drive upstream to the system, but has its own downstream floppy controller interface (using no FDC chip). Initially that lets you read and clone all the magnetic data from the floppy and store or copy it. It can also be used to reverse the process to make a new perfect clone of the floppy from storage. Note that this technique doesn't need to know anything about the format or organization of data/sectors/skew/interleave/density etc. Technically this would be able to clone any drive, even if its not FM/MFM (Apple and Commodore used some data packing formats on floppies that this could clone to an new floppy without knowing the format involved, conceptionally even variable track speeds could be copied).
I don't yet know about hard-sector cloning, that technically is more complex to this sort of design but as hard sectored is a small family, it should just be a software module that responds to the characteristic number of index pulses (index+sector) and runs accordingly. As hard sector is a small piece of the pie, I'll look at it last.
An interesting thing I'm looking at in the early stage is a fake floppy design that allows you to read any physical floppy in a different side/density/sector format behind the fake-floppy and have the fake floppy reformat that data into the floppy format that the system (CP/M computer) reads; i.e. you don't have to change you CP/M floppy definitions. If all you read and write is 40 track SSSD floppies, the fake floppy will read a 8in DSDD downstream and LIE to your CP/M and give you files in SSSD or whatever you use. But as floppies are a dying media, this is more WAY COOL than useful.
Retro System Interface to Modern Peripherals:
PC HDD ANSWER:
For early PCs, the system needs a retro interface to SATA drives. SATA can be used in a default IDE protocol which really simplifies things. Just a matter of designing an IDE board for early PCs with an intelligent controller to make peace between the two sides. You won't get all the speed advantages of SATA because an intelligent controller will have to buffer and spoon-feed the early PC. Note you likely won't be able to access the complete modern SATA drive's capacity, but you could expand the amount used with a logical drive mapping such as C:,D:... Z:. While we might not be able to use that much data storage, its offensive not to be able to access everything you've bought. Solution, SATA logical banking to reuse some of the C:-Z: drive names.
CP/M HDD ANSWER:
HDD for non-PC systems: An interface to SATA drives can be designed for the CP/M era but you won't be able to access Terabytes of storage through a 64K page; it might take you a week to key in all the multiples of remapped drive names. You won't get all the speed advantages of SATA because an intelligent controller will have to buffer and spoon-feed the CP/M system.
My thinking is to make such a SATA drive a shared external so that can improve the use of the drive by allowing your other non-PC systems access it via an external shared comm link like cheaper RS-422/485; not RS422 direct... hiddon on the other side of the fake-floppy drive (concept similar to a storage drive on ethernet). The advantage here is if you have three systems, you don't have to buy 3 SATA drives (no one is that dedicated to CP/M). As these CP/M systems are all so unique, my solution is to go for the common high-speed interface, the floppy cable. A floppy emulator (I prefer the less pretentious term "Fake Floppy" drive) is really the ideal way to tap into non PC, CP/M era computers. But forget that floppy counter interface (that's poorly thought out). Technically you can hang anything on the other side of a fake-floppy (including universal Floppy reading drives). SCSI interfacers won't like that but the floppy interface serves the greater community... maybe SCSI and more unique solutions could be a later variant.
CP/M FLOPPY ANSWER:
This typically requires something (1) to read old floppies, recovering everything possible (instead of PASS/FAIL), (2) to store images on modern computers for storage on HDD/DVD/CD/USB/CF, (3) to recreate a new floppy in any format to use or store, (4) to read useful transportable media like CF/USB.Mem/uSD/ as if it were your boot floppy, (5) maintain a RomDrive on your floppy cable to access you entire collection of floppy disks (why wear-out your floppies). Note that a cost effective NAND Flash rom, 1GBYTE (bytewide) single chip is ~$6 in production but it takes an intelligent controller to better access it, hence a fake floppy solution.
Thats more easy than it sounds: That means you can store all the information from your old floppies in one small solid state card.
To read floppies universally, I hear there are several groups addressing this various ways. I decided to do my own as a fake floppy that emulates a floppy drive upstream to the system, but has its own downstream floppy controller interface (using no FDC chip). Initially that lets you read and clone all the magnetic data from the floppy and store or copy it. It can also be used to reverse the process to make a new perfect clone of the floppy from storage. Note that this technique doesn't need to know anything about the format or organization of data/sectors/skew/interleave/density etc. Technically this would be able to clone any drive, even if its not FM/MFM (Apple and Commodore used some data packing formats on floppies that this could clone to an new floppy without knowing the format involved, conceptionally even variable track speeds could be copied).
I don't yet know about hard-sector cloning, that technically is more complex to this sort of design but as hard sectored is a small family, it should just be a software module that responds to the characteristic number of index pulses (index+sector) and runs accordingly. As hard sector is a small piece of the pie, I'll look at it last.
An interesting thing I'm looking at in the early stage is a fake floppy design that allows you to read any physical floppy in a different side/density/sector format behind the fake-floppy and have the fake floppy reformat that data into the floppy format that the system (CP/M computer) reads; i.e. you don't have to change you CP/M floppy definitions. If all you read and write is 40 track SSSD floppies, the fake floppy will read a 8in DSDD downstream and LIE to your CP/M and give you files in SSSD or whatever you use. But as floppies are a dying media, this is more WAY COOL than useful.
bonedaddy
Member
Hi, Yes, I have XT-IDE V2 bare boards available. The boards are $12 each plus $5.95 for shipping in the US. I also have most of Sergey's ISA bare boards available (http://www.malinov.com/Home/sergeys-projects) and it's the same shipping cost for multiple boards. PM or email me at tsg at bonedaddy.net.
Todd
If you dont have the right equipments and skills (like me), you would probably do more damage then good
@jDallas. i rather use my old HDD and my old FDD then installing new hardware (just for now). But when the time comes i would rather then use a sata drive as you say and maybe a FC card as a "floppy"
But old floppys is WAY cooler and feels more right to use for these old systems
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There must still be lot of them out there, take a look
http://www.ipernity.com/doc/78280/12052035
http://www.ipernity.com/doc/78280/12052035
Chuck(G)
25k Member
What's "when the time comes?"
Hard drives can work for a very long time--I still have an ST506 that works just fine (not to mention an SA4000).
I like the CF adapters because they're convenient. I even have a few that work in systems with a regular IDE interface, but mount the adapter on a bracket, so you can change "hard drives" without even opening up the machine.
While a 4GB CF card may seem small today, in terms of what was available for XTs, it's enormous, gigantic--you will not fill it up.
Hard drives can work for a very long time--I still have an ST506 that works just fine (not to mention an SA4000).
I like the CF adapters because they're convenient. I even have a few that work in systems with a regular IDE interface, but mount the adapter on a bracket, so you can change "hard drives" without even opening up the machine.
While a 4GB CF card may seem small today, in terms of what was available for XTs, it's enormous, gigantic--you will not fill it up.
No "today"
Yes i will get one also when i can, since you need to assembly it by your self. Me and soldering = bad idea lol