This project provides the CAD files for an STM32-based floppy-disk controller that can be attached to the back of an ordinary 3.5 inch floppy-disk drive and connected to a USB host via micro USB port.
The core of this adapter is the popular STM32F103C8T6 microcontroller by STMicroelectronics. Please consult the PDF schematic for details.
The adapter can be used in several different hardware configurations that can be selected via solder bridges.
The following drive types are supported:
- PC drives
- IBM PS/2 drives
- drives with shugart interface
Drives that only use the 5V line and consume less than approx. 480mA can be powered via USB, other drives have to be powered externally.
| J5 | J6 | J7 | Use case |
|---|---|---|---|
| ▒▒░▒▒ | ▒▒░▒▒ | ▒▒░▒▒░▒▒ | PC drive, externally powered |
| ▓▓▓▓▓ | ▒▒░▒▒ | ▒▒░▒▒░▒▒ | IBM PS/2 drive without 12V line |
| ▒▒░▒▒ | ▓▓▓▓▓ | ▒▒░▒▒░▒▒ | PC drive, USB-powered |
| ▒▒░▒▒ | ▒▒░▒▒ | ▓▓▓▓▓░▒▒ | pin 4 and 6 shorted, for shugart drives that do not use pin 4 |
| ▒▒░▒▒ | ▒▒░▒▒ | ▒▒░▓▓▓▓▓ | 12V on pin 4, for PS/2 drive |
The power connector J3 can be used as either input or output.
Configurations other than the USB-powered PC drive (see picture) are untested.
As of August 2020, there is no working firmware for this adapter, yet.
The objective is to adapt the firmware provided by the Greaseweazle project. It does already provide support for the same microcontroller, albeit for a much bulkier adapter with a different pinout.
The adapter provides solder pads for an SWD programming device. They are labeled J4 on the PCB.
| Pin on J4 | Function |
|---|---|
| 1 | 3.3V |
| 2 | SWDIO |
| 3 | SWCLK |
| 4 | GND |
Please refer to the Greaseweazle documentation for PC-side software that will be used with this adapter.
The following license applies to the files in this repository:
This work is licensed under the Creative Commons Attribution-ShareAlike 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-sa/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.