Emulate Floppy with a Raspberry Pi ?

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jedie
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Re: Emulate Floppy with a Raspberry Pi ?

Post by jedie »

Ah! /me i should really read the text :oops:

Very interesting!

But feels not as a physical floppy drive?

btw. i found stuff around to emulate floppy drives with the raspberry pi:

Ninepin
Ninepin is about interfacing retro computers to modern peripherals.
e.g.: Use USB joystick via RPi GPIO with Commodore 64, Atari 2600, and Sega Master System
emulate the disk interface to the Commodore 64 IEC serial bus
https://github.com/FozzTexx/ninepin
... too many ideas and too little time ... Related stuff written in Python:
Dragon 32 emulator / PyDC - Python Dragon 32 converter: https://github.com/jedie/DragonPy
DWLOAD server / Dragon-Lib and other stuff: https://github.com/6809
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tormod
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Re: Emulate Floppy with a Raspberry Pi ?

Post by tormod »

jedie wrote:But feels not as a physical floppy drive?
When using DriveWire the server acts as disk controller and floppy drive. So you still use a DOS (HBD-DOS) like if you had a real floppy drive, but extra drivers in HDB-DOS send translated disk controller commands over the serial line to the server (and receive the disk data).
btw. i found stuff around to emulate floppy drives with the raspberry pi:
Emulating the Commodore disk controller is easier since it uses a serial interface. But processing all the necessary pins on the Dragon bus to decode addresses and then sending out the data on the data bus within the time the Dragon expects it might be difficult for the RPi. Though I would be delighted to be proven wrong :) If you add some circuitry (latches, address decoding) in between it might be possible.

It seems better to use DriveWire instead, unless you have some special programs that wants to talk directly to the disk controller short-circuiting the DOS so that you really need full controller emulation.

If the serial line used for DriveWire is not fast enough one could think of using a parallel interface like the Becker port between the Dragon and the DriveWire server. I think Cloud-9 is cooking on something like that. With HDB-DOS for Dragon we can join the fun!
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tormod
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Re: Emulate Floppy with a Raspberry Pi ?

Post by tormod »

tormod wrote:But with its serial UART it makes for a great DriveWire server!
I read a bit about the RPi and it seems that it only has one UART available on the pin headers, and this one is used as serial console (for kernel messages and terminal login). So for DriveWire you will have to use the USB port (like on a normal computer) or disable the serial console (explained here https://sites.google.com/site/semillero ... rials/gpio).

EDIT: Hmm there should be a second one: http://lavalink.com/2012/04/more-on-ras ... ial-ports/ In any case you will need some circuitry for inverting and level shifting before you can connect it to the Dragon.
jedie
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Re: Emulate Floppy with a Raspberry Pi ?

Post by jedie »

It seems that it is possible, read: http://www.raspberrypi.org/phpBB3/viewt ... 41&t=34143
... too many ideas and too little time ... Related stuff written in Python:
Dragon 32 emulator / PyDC - Python Dragon 32 converter: https://github.com/jedie/DragonPy
DWLOAD server / Dragon-Lib and other stuff: https://github.com/6809
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tormod
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Re: Emulate Floppy with a Raspberry Pi ?

Post by tormod »

Very interesting! I hope you get more information from the guy.

Again, this looks like a serial (one data line) floppy drive interface. The floppy drive is emulated, not the controller.
jedie
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Re: Emulate Floppy with a Raspberry Pi ?

Post by jedie »

tormod wrote:The floppy drive is emulated, not the controller.
Yes, but this is also a nice way: Use a controller clone (like the one from lafumat) and emulate the floppy with Raspberry Pi to share the files directly into the local LAN ;)

OK, emulate floppy controler + floppy drive would be nicer... And maybe the DriveWire solution is much easier to realized.
... too many ideas and too little time ... Related stuff written in Python:
Dragon 32 emulator / PyDC - Python Dragon 32 converter: https://github.com/jedie/DragonPy
DWLOAD server / Dragon-Lib and other stuff: https://github.com/6809
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JeeK
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Re: Emulate Floppy with a Raspberry Pi ?

Post by JeeK »

jedie wrote:It seems that it is possible, read: http://www.raspberrypi.org/phpBB3/viewt ... 41&t=34143
Very interesting, but to summary up (if I got it right): The authors version supports only FM (single density) so far (someone other intends to add MFM support), there are only some pictures, no schematic or PCB for the supporting electronic, nor any code online ... :(
The dragon on my side: http://klasek.at/hc/dragon/
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JeeK
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Re: Emulate Floppy with a Raspberry Pi ?

Post by JeeK »

JeeK wrote:
jedie wrote:It seems that it is possible, read: http://www.raspberrypi.org/phpBB3/viewt ... 41&t=34143
Very interesting, but to summary up (if I got it right): The authors version supports only FM (single density) so far (someone other intends to add MFM support), there are only some pictures, no schematic or PCB for the supporting electronic, nor any code online ... :(
The author Alan Page offers direct email contact on request (via PM on the RPi site). ;)
The dragon on my side: http://klasek.at/hc/dragon/
jedie
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Re: Emulate Floppy with a Raspberry Pi ?

Post by jedie »

from http://www.raspberrypi.org/phpBB3/viewt ... 36#p426632 :
alpage wrote:I have started a blog at http://virtualfloppy.blogspot.ca/ for this project. People can ask questions and leave comments there.
A future idea: What's about a "General-purpose cartridge" emulation with the RPi ? e.g. emulate a ROM cartridge or a floppy just by change the software in the RPi ?
Maybe some translator electronics are needed, because the RPI GPIO are to slow?

Actually someone already had this idea. Maybe a FPGA solution?
... too many ideas and too little time ... Related stuff written in Python:
Dragon 32 emulator / PyDC - Python Dragon 32 converter: https://github.com/jedie/DragonPy
DWLOAD server / Dragon-Lib and other stuff: https://github.com/6809
jedie
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Re: Emulate Floppy with a Raspberry Pi ?

Post by jedie »

Maybe the new FPGA for Raspberry Pi can help:
pif is a Field Programmable Gate Array (FPGA) add-on board for the Raspberry Pi.
-> http://www.bugblat.com/products/pif/
... too many ideas and too little time ... Related stuff written in Python:
Dragon 32 emulator / PyDC - Python Dragon 32 converter: https://github.com/jedie/DragonPy
DWLOAD server / Dragon-Lib and other stuff: https://github.com/6809
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