The emulator can emulate two drives, by answering to different "drive select" and/or "motor on" pins. How does multiple ready signals work for you ? On all computers I know there is a single ready line connected to all drives. I'd expect the READY signal for each drive to be active only when the matching "drive select" is active ?
Yes, you are perfectly right pulkomandy
, this is the standard behaviour. As per the Shugart
standard, the drives receive separate SELECT
signals and a common MOTOR ON
signal and the drive selected responds by activating the common READY
Later on, IBM changed things a little when they introduced the cable twist, at which point they introduced individual MOTOR ON signals for the two possible drives on the cable (so NOW that means separate SELECT
and separate MOTOR ON
Well my computer is even more detailed, its floppy controller has also separate READY
signals. I'm attaching here the schematics of the floppy interface so you can see what I'm talking about.
I'm sorry, I just realized I was wrong when I said: "Because if so, I don't see two separate READY signals coming out of the emulator. And I strongly suspect your device CANNOT actualy work as two separate drives connected at the same time".
Obviously, your device DOES
comply with the Shugart standard from this point of view. What I should have said is "HxC may not work with my particular floppy interface because this interface uses individual READY signals"
But I just figured right now, if you look at the schematics on page 2, I could simply bypass the multiplexer U04 and use a common READY signal from all drives, right?
I only have one real question left: how can the HxC work if it ignores the MOTOR ON signal? If I'm not wrong the manual says: "Unlike real floppy disk drive the SDCard HxC Floppy Emulator doesn’t use the
motor control line. So there are only one jumper to set per virtual disk drive."
So how can it work if it ignores the MOTOR ON?
Second: thank you for explaining, I didn't know the configuration file can actually change the location of signals on the connector pins. That is really useful !
And for Jeff: I meant "2 drives connected to the cable
AT THE SAME TIME", that is the drives are connected to the same cable at the same time, but of course they will NOT be ACCESSED simulaneously, that's impossible, I realize that
So I guess the only question for me is: does SDHxC really ignore the MOTOR ON signals? And if so, how can it work this way?
Thank you all guys, I appreciate your assistance.