Arduino Amiga Floppy Disk Reader/Writer aka DrawBridge

Open Source and Free! - by Robert Smith

Build One!

Building your own reader/writer isn't very difficult as most of it is just wiring. This can be done on a breadboard, breakout board or soldered together.

New: Join the Waiting List for purchase of a ready-built solution!.

Build your own USB slimline floppy drive (if you have decent soldering skills) See instructions

For help and discussion, check out the Discord Server

For people who speak German, check out this older guide by Mingo., there is also this video which goes into a lot of detail of building this.

Which version do you want to make?

There is no difference in performance, the choice you make should be based on your (soldering) skill level (or if you like a challenge - see the Nano!):

Arduino UNO
Arduino Pro MiniArduino Nano
View Instructions
View Instructions
View Instructions

Requires an FTDI USB to Serial Adapter Board (DO NOT USE THE CH340 BOARDS)
No Soldering solution available
Requires a soldering iron
Requires good soldering skills (or at least not your first attempt!)

Upgrading your existing read/write board (WinUAE)

If you already have a board and want to upgrade it to get the best possible experience within WinUAE then you need to make the following modifications. These changes allow the Arduino to detect if a disk is inserted or not, and allows it to control th drive without spinning up the motor. Without these changes, the Arduino code will spin up the drive at regular intervals to perform a check manually:

If the above doesn't make sense, check out the new diagrams for each board.

PC 34-Pin IDC Cable Guide

Assuming you have cut the cable and the piece you are using does not have the twist in it, then locate the wire with the red stripe. This is Pin 1, and they continue in sequence, every other wire being a GND. You usually don't need to connect up the GND wires as they are all connected together anyway inside the drive.

If you are having trouble with the floppy drive cable then the following diagram might help (the red line is the red marking on the cable. Make sure you aren't using the part of the cable with a twist in it):

Programming the Arduino

Once you have all of the wiring complete, you now need to upload the program onto the Arduino. It's easy.

  1. Download and install the Arduino IDE.
  2. Connect the Arduino to the computer as follows:
    • Arduino UNO: Use the on-board USB connector
    • Arduino Pro Mini: Use the break-out board
    • Arduino Nano: Use the on-board USB connector (if it fails, try the old bootloader option)
  3. After a few moments the drive should be detected and be ready to use. If not you may need to install additional drivers. You may need to restart your computer, although sometimes just disconnecting and reconnecting a few times achieves the same result.
  4. From the Arduino IDE select the type of board from the Tools->Board menu:
    Board selection in the Arduino IDE
  5. Next, choose the COM port the device is connected on from the Tools->Port menu:
    Board selection in the Arduino IDE
  6. To test the board, I recommend first programming it with the BLINK example. Goto File->Examples->Basic->Blink - if you're feeling brave, change the numbers in the delay() functions to 100, that'll blink a lot faster.
  7. Now upload the blink program by going to Sketch->Upload. Some LEDs should flash for a while on the board, and then afterwards, you should see one of the LEDs turning on for one second, then turning off for one second, repeating.
  8. Once you're happy thats working, download the Arduino sketch from either GitHub or from this website. and load the file into the IDE.
  9. Now program it in the same way as before, by going to Sketch->Upload.


So, you've connected everything up and you've programmed your Arduino. I've included a diagnostics option to help you figure out if everything is working correctly. You will need a floppy disk that you don't care about, and the application available on the downloads page. This will run through a series of tests which should help you troubleshoot. Either that, or just go for it and try it out!

More Help and Other Guides

If you get stuck, there are loads of good examples showing you how to set up and get started with Arduino, for example: