Embedded System R/W information from Floppy Disk

floppy driver i8272

Hi, I'm new here, hope anybody can help:

I'm projecting an embedded system wich you'll need to store/read information from a non-volatile, high-capacity, permanent memory device. I thought about trying to use the system microcontroller to control an old 486 floppy disk drive, as I don't want to spend money with other devices...

My question is: is it possible to use a Z80 or 8051 to control a floppy disk driver? If it is, where can I find the pin assignment of those 3 1/4 ' floppy disk driver used in nowadays computers ?? Please, post some links so I can find myself in this mess... Hope I made myself clear! Thanks again,

Erick

8051 floppy sd

To be honest, I think you should rethink your storage...

1) Floppy disks are notoriously unreliable, certainly not permanent

2) The interface is very tricky

Basically, the interface required a 500kbps, with weird timing to get the data directly onto the disk surface as it spins. It is not like writing to a hard disk, where you just send data and the drive's electronics takes care of writing it. I have never come across a good solution to this.

It would probably end up cheaper to work a solution with CF or SD card memory, for which off-the-shelf commercial and DIY solutions can be easily found on the 'net.

However, here are some links to the floppy interface:

http://ohlandl.kev009.com/floppy/Floppy_Pinouts.html
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Your only hope, I think, and it is a very small one, would be to locate an old floppy controller chip i a very old computer and salvage it. Then find the datasheet for it. etc, etc. As far as I know, these are not in manufacture any more as the floppy control is integrated with everything else in a PC.

Just a thought, do you need to actually remove the storage device? You son't say so. If not, it would be cheapest to just put in some big flash chips!


Cheers,
FoxyRick.

Check this:
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This is the datasheet of controller chip

http://www.intel.com/design/archives/ periphrl/docs/29046803.pdf

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Hi , there are two components in a floppy drive system.
the controller and the drive ... To design a controller is a major task..
The controller is 80 % of the system .. The drive is very simple ..is just a read channel and a head amplifier .. with the motors interfaces .. But is only 20% of a system .. then you need a PLL to restore a clock a MFM endoder/decoder ,precompensation circuitry clock generators ,etc ,then all the formating structure ..The only and cheap way to do it is to find an old pc 8 bit card controller .. Chances are that the floppy controller may be a NEC (exteded intel 8072A) a National or other ,, then you will have to get the datasheet ..(don't bother for the national is long time been obsoleted ..but i have it if you need it) Also you need a PC computer hardware book to see where are the registers mapped .. ! Now .. the transfer between the PC and the floppy unit is done by interrupts ,,and the amount of data is at most of 500k or less ..so you need a micro with a lots of ram , and capable of sustaining that bandwidh ..
i did an IP for MFM enocoding if you need it i can give it to you .but you will need a valid deserialiser for that frequency <ALL ARE OBSOLETE> this days .My IP is intended to work with a TRISCEND E5 .. where a DMA is avalaible .. .. I think it'll be wiser to go with a flash file system and flash cards
SDM card are cheap $30 for a 120Meg ... What is that? ... 100 Floppies !!!!

Maybe I should rethink the way data will be stored in this system ... Maybe I'll go for Flash Ram ... Anyway, thanks for the links and replies too!

Erick