A nice module for the Virtual-Disc project?

This is the right place to discuss on how to implement hardware vsync, adding a VIA or AY chipset, puting multiple roms, or how to design a new flash expansion card.
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ibisum
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A nice module for the Virtual-Disc project?

Post by ibisum »

Perhaps this is a nice module for consideration by those of us currently thinking about adding a virtual-disc-drive to our machines?

http://www.4dsystems.com.au/prod.php?id=22

Seems to me that something like this, perhaps paired with the Hackaday Bus Pirate board (very cool, I ordered one), could be paired together to do some very simple disc emulation? What do you guys think?
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Post by JamesD »

If you don't mind paying $29+shipping for each one.
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Post by ibisum »

Shipping cost me 12eu,- .. and I bought a couple other things too.

But thats not the point, which is: will they work out, technically? I will see and let you know.
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Post by JamesD »

It still requires a serial port to talk to it. Other than that I don't see any technical reason you couldn't hook it up.

But then it's just another serial drive like the ones for Atari and C64 but without software to manage disk images. I'm not sure what you are gaining here. To emulate a disk drive would still require another MCU and there is already source code to support FAT over a serial connection to an SD/MMC card for PIC MCUs.
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Post by waskol »

hmm, something I would see to emulate various extension and create new ones is this one :
Image
Arduino MegaBoard This Open Source I/O interface can be used linked to the PC via USB2 (and be used as an interface between the Oric, and for instance a netbook), and can operate alone.

Code: Select all

Microcontroller	ATmega1280
Operating Voltage	5V
Input Voltage (recommended)	7-12V
Input Voltage (limits)	6-20V
Digital I/O Pins	54 (of which 14 provide PWM output)
Analog Input Pins	16
DC Current per I/O Pin	40 mA
DC Current for 3.3V Pin	50 mA
Flash Memory	128 KB of which 4 KB used by bootloader
SRAM	8 KB
EEPROM	4 KB
Clock Speed	16 MHz
Each of the 54 digital pins on the Mega can be used as an input or output, using pinMode(), digitalWrite(), and digitalRead() functions. They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. In addition, some pins have specialized functions:
I am pretty sure one can create a "Microdisc" or a Jasmin drive from it, working from a SD card reader or the PC, a modem, a programmable Joystick interface, a printer interface, a joystick interface for "modern" gamepads, and so many other usefull (or useless) things for an Oric.

I even wonder if it could emulate an Oric itself : just add a PS/2 keyboard, a SD card reader, and... a monitor or a TV, etc...

this thing costs 50 euros (not so expensive)
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Post by JamesD »

The biggest problem with an FPGA replacement is normally cost. It's usually a board over $100. It takes a pretty big FPGA to hold an entire machine. The biggest problem is the space required for the CPU, ROM and RAM. If you don't mind plugging adding a real 6502, ROM and RAM then a cheap FPGA can more than do the job.
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Post by ibisum »

waskol: I have an Arduino rig .. but the Mega definitely has the i/o to do the job.

For now, I'm going to get the Bus Pirate and the SD interface rigged up .. I'll control the SD with the Bus Pirate serial i/o, and use the Bus Pirate i/o itself to try to implement a rudimentary emulation mode of the microdisc .. I think this will work, and the advantage is that this is exactly the sort of thing the Bus Pirate is designed to do .. surely, if it works out, I can use what I learn to program an AVR (or Arduino Mega) to do a full-blown design - but as I am a programmer, and very inexperienced with hardware, the Bus Pirate is a bit more approachable for me at the moment (plus I want a nice project to learn how to use it)..

Anyway, good that we're discussing this .. here's hoping we can come up with something that works in the near future.
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Post by waskol »

ibisum :
At least, with the Basical Arduino, you could develop some interface for the Printer port, I think :
- PASE compatible Joystick interface
- Voice synthesizer
- Optical pen ???
- MCP40 Printer emulator !

ibisum wrote:Anyway, good that we're discussing this .. here's hoping we can come up with something that works in the near future.
Who knows !

Edit : by the way, look at this !
http://www.e-robotix.de/epages/61660837 ... ucts/Prop1
The propellurino can be used together with an arduino. The propellurino is a so called "shield" for an arduino microcontroller board.

It enhances the Arduino in several ways because it has a lot of interfaces the arduino doesn't have.

features
- VGA connector
- PS2 mouse or keyboard interface
- MIDI in - microphone connector
- audio out connector
Watch this : http://www.youtube.com/watch?v=89M5rvolGGU

It seems we almost have an Oric on a chip there ;)
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