MiSTer FPGA Forum

Lukage wrote: ↑Tue Dec 15, 2020 4:58 pm

Caldor wrote: ↑Tue Dec 15, 2020 12:41 pm Wont it also need that USB board? The first point does not seem to go into that. Dont you have a board blueprint for that or something that we can then either make ourselves or order from some PCB maker?

Actually, no, you don't need that board. In this GPIO version, that board serves only as a level converter with open-drain outputs. You just create any type of suitable level conversion for 5V floppy signals, and connect it with analog board. There are holes in analog board on unused GPIO pins, just use some jumper wires. This is that 5 additional GPIO pins. User port has 7 pins in total, on USB3 connector. Just use USB3 A connector with short wires from it, and you are good to go. If you don't have any connector or you don't want to cut any USB3 cable to get a nice pigtail, just solder some jumper wires to analog board on pins used by USB3 user port. Just connect all these wires to some prototyping board (solderless breadboard or some PCB), and do some level conversion on that board.

This is experimental setup, so please don't fry your DE10-Nano boards ! Remember, you can't connect floppy drive directly !

UgoR934 wrote: ↑Sat Dec 19, 2020 12:10 am I don't have the I/O board in this house to double check directly on that PCB if something etched over there can help finding out.

PIN_U14   IO_SCL      STEP
PIN_AG9   IO_SDA      TRACK0
PIN_AF17  USER_IO[6]  DSKRD
PIN_AF15  USER_IO[5]  WPROT
PIN_AG16  USER_IO[4]  DSKCHG
PIN_AH11  USER_IO[3]  DIR
PIN_AH12  USER_IO[2]  SIDE1
PIN_AH9   USER_IO[1]  MOTORB
PIN_AG11  USER_IO[0]  DRVSELB
PIN_AH8   SD_SPI_MISO INDEX
PIN_AG8   SD_SPI_CLK  DKWD
PIN_U13   SD_SPI_MOSI DKWE

Arduino_IO0 PIN_AG13 Arduino IO0 RXD 3.3-V
Arduino_IO1 PIN_AF13 Arduino IO1 TXD 3.3-V
Arduino_IO2 PIN_AG10 Arduino IO2 3.3-V
Arduino_IO3 PIN_AG9 Arduino IO3 3.3-V
Arduino_IO4 PIN_U14 Arduino IO4 3.3-V
Arduino_IO5 PIN_U13 Arduino IO5 3.3-V
Arduino_IO6 PIN_AG8 Arduino IO6 3.3-V
Arduino_IO7 PIN_AH8 Arduino IO7 3.3-V
Arduino_IO8 PIN_AF17 Arduino IO8 3.3-V
Arduino_IO9 PIN_AE15 Arduino IO9 3.3-V
Arduino_IO10 PIN_AF15 Arduino IO10 SS 3.3-V
Arduino_IO11 PIN_AG16 Arduino IO11 MOSI 3.3-V
Arduino_IO12 PIN_AH11 Arduino IO12 MISO 3.3-V
Arduino_IO13 PIN_AH12 Arduino IO13 SCK 3.3-V
Arduino_IO14 PIN_AH9 Arduino IO14 SDA 3.3-V
Arduino_IO15 PIN_AG11 Arduino IO15 SCL 3.3-V
Arduino_Reset_n PIN_AH7 Reset signal, low active. 3.3-V

Lukage wrote: ↑Sat Dec 19, 2020 11:07 am

UgoR934 wrote: ↑Sat Dec 19, 2020 12:10 am I don't have the I/O board in this house to double check directly on that PCB if something etched over there can help finding out.

If you don't have I/O board, the job is far simpler. Just use DE10-Nano manual, pages 30 and 31. There is Arduino header pinout. As I posted earlier:

UgoR934 wrote: ↑Sat Dec 19, 2020 5:41 pm I've a small batch (qt. 8) of CD4050,

UgoR934 wrote: ↑Sat Dec 19, 2020 5:41 pm if you have a photo "closeup" of wires of your board

C5484 wrote: ↑Sat Dec 19, 2020 6:41 pm so if i understand correctly, for those who want to replicate your results need a DE10-nano, some wires, lvl converter and a PC floppy drive

C5484 wrote: ↑Sat Dec 19, 2020 6:41 pm I am designing and building a plastic case for the MiSTer, incuding a keyboard and the FDD.

Oh, and that argh ao486 note: density select pin is not needed for that. It should work both for DD and HD disks in DOS.

UgoR934 wrote: ↑Wed Dec 30, 2020 12:34 pm I thought this PIN was needed to format a DD 360K 5"1/4 floppy disk inside a HD 1,2M floppy drive. Is it true or false?

ByteMavericks wrote: ↑Fri Feb 26, 2021 11:43 am Thinking aloud, would it be possible to use this work as the basis for improving the disk activity light to reflect MOTOR_ON as it does in the Amiga - rather than DMA_ON which is what it does now if I understand correctly - and secondly to pass more signals back up to the ARM side with a view to adding in floppy sounds? (Or is that not possible due to the way HDMI is provided by the core?)

Apologies for my ignorance, keen to learn!

Lukage wrote: ↑Sun Dec 20, 2020 2:05 pm Posting patches & compiled binaries with updated write code.

UgoR934 wrote: ↑Wed Dec 30, 2020 12:34 pm

Oh, and that argh ao486 note: density select pin is not needed for that. It should work both for DD and HD disks in DOS.

Sorry, not trying to be nitpick.. but just to discover something every day: back in the day, I thought this PIN was needed to format a DD 360K 5"1/4 floppy disk inside a HD 1,2M floppy drive. Is it true or false? I could imagine that 3,5" drives can just auto-configure themselves by checking the second hole, but I can't remember "an hole" for 5 1/4 HD floppies (instead, I could remember that you can force HD format on a SD, of course with disasters coming in seconds).

Also.. THANKS for your updated pinout!

Finally - again - a request for help.
I checked out CD4050B schematic (the only chip I have to do level conversion here):
cd4050b.gif

I looked at I/O schematic (I think you also pointed out) and the output seems open-collector. In input, I don't think I will need anything to get a stable logic. So my proposal is this one (ex. for a single input and a single output):

cd4050b-levelconversionexample.gif

Do you think it's ok?

retrorepair wrote: ↑Wed Apr 21, 2021 1:18 pm

Lukage wrote: ↑Sun Dec 20, 2020 2:05 pm Posting patches & compiled binaries with updated write code.

Could you possibly look to get some of the floppy controller improvements merged?

There's no reason they shouldn't be if they achieve more accurate behaviour.