The Sinclair QL Forum

i wonder they are any schematics for floppy disk interfaces ? like (example)CST Q Disk Interface

nikosdoykas wrote:i wonder they are any schematics for floppy disk interfaces ? like (example)CST Q Disk Interface

On Dilwyn's page is a circuit diagram for the SuperQBoard.

nd many roms olso.

any schematics for this????

what's the part number on the large black chip underneath the Eprom with the white label on it ?

wd1770......

that makes sense - that's the disk controller chip

To answer your question: To my knowledge, there's no QDISC interface schematics anywhere. But it should be pretty simple, considering there's not much in there.

It doesn't look to have address jumpers like the qubide board - and as an official interface that's got the sinclair stamp, it would have to decode SP0-SP3 slot address used in combination with A17-A14 to locate the board's position in the memory map - by default this would be at 0x0C0000 - the first expansion card address with A19=1, A18=1. The Eprom chip would start at that address, and there should be an 8 bit latch with drive I/O signals, plus the WD1770 chip itself probably decoded in the last 256 bytes of that 16K block, starting from the base address. It will be similar to many of the Disk interfaces built around the WD177x series chips. I am not sure if the manuals give anything away about the I/O addresses ?

nikosdoykas wrote:any schematics for this????

Hi

Two options:

1) Remove the cover and take a high resolution photograph of both sides and post it here, I can probably try and get a schematic attempt done.

2) Send the interface to me and I will try and determine the schematic from an examination of the interface.

I have two Q-Disc Interfaces, so maybe a the photo route is best and I can compare the PCBs.