Epson SD-600 problem with STM32F103C8T6 Direct Connection about greaseweazle HOT 8 CLOSED

Does the adapter board have the 4x1k resistors attached?

from greaseweazle.

Yes. It is one out of your production.

from greaseweazle.

Then either the dupont wires are not making good connection or, more likely, you need 1k pullups on inputs from the drive.

from greaseweazle.

I tried with a 3.5 Floppy, Epson MPF-920-E.

There is no problem. It seems to be a problem with the specific combination floppy-blue pill/dupont.

from greaseweazle.

Lack of 4x 1k pull ups on the inputs. Add them and it will work fine.

from greaseweazle.

To be sure:
At „Blue Pill“ connect B6/INDEX, B7/TRK0, B8/WRPROT, B2/DKRD over resistor 1K to 5V. Right?

from greaseweazle.

Yes. Each gets a 1k resistor as you say. Four resistors total.

from greaseweazle.

I can confirm that the problem is solved with the pull up resistors.
Maybe a note telling about the pull ups in the Hardware Assembly section would be helpful.

from greaseweazle.