Floppy Adapter for IBM PS/2 Model 85XX (55 / 56/ 57 / 90 wSLX)

This project is the result of the excellent (pre)work of https://github.com/jtgans/PS2FF/

It has been modified to integrate the last missing piece to make it working.

This card has been tested on a IBM PS/2 8557, and it is working like a charm with a GOTEK like floppy.

The current design is made simple with Troughhole

The licence is creative commons CC-BY-SA

Work based on

• JUNE TATE GANS
• june@theonelab.com
• https://github.com/jtgans/PS2FF

###This is the first release, small todo:

• Change the BXC337 transistor and the TTL 74HC125 by a 74LS245 with using the 2nd line of buffer to manage the FDD Density select.
• Change the design to SMD to make it more compact

Bill of Material

• 5x 1K resistor
• 1x CAP Ceramic 10pf (noise filter)
• BC337 transistor
• TTL 74LS125 or 74HC125 (prefer the HC)
• PS/2 Male pin connecter (LCSC ref C707014)
• Floppy Female pin connector right angle (LCSC ref C2897437)

Changes compare to June version:

• Different PCB routing
• Trough hole design
• JP2 Jumper to short PS2_DATA_RATE pin with FLOPPY_DENSITY_SELECT
• BC337 Transistor to inverse FDD_DENSITY