Overview

One of the most needed accessories for the Sharp MZ series is the venerable Floppy Disk Controller. These are in relative short supply as not many people used them, mainly due to cost, during the Sharp MZ era.

Sharp released their own controllers often based around the MB8866 IC which needed a lot of support circuitry. A few 3rd parties developed their own and one design, by a company (no longer in existence) called Kersten & Partners GmbH (K&P) developed a much simpler design but with no less functionality.

This design used a newer Western Digital Floppy Disk Controller IC, the WD1773 which incorporated a lot of the circuitry which Sharp, using the MB8866, had to place externally on the circuit board.

This is a recreation of the original card with custom GAL decoder logic (original used a PAL) and more modern PCB layout technique.

It maintains full compatibility with the original SFD-800 and has been tested in numerous machine including the Sharp MZ-80B, MZ-800, MZ-1500, MZ-2000 and MZ-2200.

Technically, this board can be made to work with the Sharp MZ-80A/MZ-700 but will require a 2KByte boot ROM and the MZ-80A requires the A10 line to be toggled by the FDC READY signal. Unless your technical, do not consider the SFD-800 for either of these two machines (MZ-80A/MZ-700).

Installation

On the MZ-80B you will need the internal expansion cage installed. This came with most machines but some machines it was an optional extra. The card slots into a free port in the expansion cage.

On the MZ-2000 and MZ-2200 you will need the external expansion unit. The card slots into a free port.

On the MZ-800 and MZ-1500 slot the card into the expansion port in the main unit.

Connect a 34pin IDC cable to the SFD-800 and the opposite end of the cable to your floppy drive. Some floppy drives use 34pin female edge connectors others use 34pin male IDC connectors (more the standard).

Switch on your machine and it will immediately attempt to boot from Floppy or show a menu with 'F - Floppy' as an option. No firmware is needed as all the machines have it inbuilt within their IPL/Monitor ROM code.

Whats Included?

1 x SFD-800 Floppy Disk Controller Board (Assembled or kit of parts)

Notes

The original design and consequently this replication has the FDC 34pin IDC connector inverted. This means the lug on the 34pin connector, which would normally face upwards and slot into the socket gap must face downwards. The connector at the floppy end connects in reverse as well.

The designs for this adapter are freely available on github for non-commercial purposes should you wish to source the parts and build the adapter yourself. Most parts are available on Ebay, ie FDC Controller IC WD-1773 costs about GBP15 from diamond10010, the FDC-34 connector is available from RS Components.