Getting a GoTek floppy drive emulator working

So here's a slightly odd post, why am I playing with GoTek floppy emulators? Well, I rediscovered my Amstrad CPC6128 8 bit computer from the '80s and wanted to try some software downloaded from various sites.

The Amstrad CPC6128 has a floppy port (34 way IDC edge connector) which is compatible with the 5.25" drive connector found on some floppy ribbon cables.

So, I hooked up the GoTek to a TTL serial cable and flashed the Flash Floppy firmware, I did the OLED screen upgrade, I even added a rotary encoder. I followed all the guides you find everywhere.

I connected the GoTek to the CPC and got some errors you would expect if there was no drive.

I linked pins 33 & 34 to set the Ready signal, I linked pins 11 & 12 to force it to be the A drive (shown below, image from CPC Wiki).

But nothing.

No guide I followed gave me any clues. That is until I randomly started researching the pinouts of the 34 way connector feeling I was missing something.

Then I found a project by a guy working on reading Amiga disks with an Arduino, he explains the entire process and linked to pinouts.ru I followed the link and started reading.

This paragraph stood out a mile!

One might ask why the twist was needed. In short, because it was a big time-saver during setup back in the days when it was quite common to find two floppy drives in a machine. Without the twist, for two floppy drives to be used, one had to be jumpered as A: and the other as B:. With the twist, it was possible to leave them both jumpered as B:, and whichever was after the twist will appear to the system as A: because the control lines are inverted.

OMG!

Drives back in the day were normally jumpered as B: by default?! This GoTek is jumpered as unit zero by default. More Googling and I find the following jumper guide. I set my GoTek as S1 (rather than S0)

Guess what?
Everything works now, I can enjoy 36 years of software (yes people still write software for an 8 bit system released in 1985 and it's predecessor in 1984. There is even new hardware out there. I have plans to add WiFi.

I might have to try the GoTek again on my Amiga, it will probably work now! 😁