Would this work with my STM32F103C8T6-based custom board?

[roybaer]

Hi!

I would like to ask whether there is any chance that your firmware might work with my custom board design from early 2018.

It uses the same STM32F103C8T6 and plugs into the back of the drive. Unfortunately, I never found the time to write proper firmware for it.

The pinout is:

µC pin	Signal	Drive pin
PA0	INDEX	8
PA3	WGATE	24
PA4	DRVSA	14
PA5	DRVSB	12
PA6	MOTEB	16
PA7	MOTEA	10
PA8	DSKCHG	34
PA9	REDWC	2
PB0	DIR	18
PB1	STEP	20
PB10	TRK00	26
PB11	WPT	28
PB12	DTID1	4
PB13	SIDE1	32
PB14	RDATA	30
PB15	WDATA	22

[keirf]

No reason why not really. Most of the pin-specific stuff is at the top of src/floppy.c. Gotchas I can see:

• Not all your pins are on GPIOA so you will need to be more flexible than my single 'gpio_floppy' defn.
• INDEX gets configured for an EXTI IRQ. Yours is on PA0 so you need to adjust the EXTI init appropriately, and your IRQ number will be different.
• The timers and DMA channels for RDATA/WDATA will be different. That's mostly abstracted at the top of src/floppy.c but the code currently assume two separate timers, whereas you are on two channels of the same timer. It shouldn't much matter, but you'll have to juggle the init/deinit code to do a fuller initialisation when switching between read and write mode.

[roybaer]

Nice! That should be doable. I'll have a look in the near future.

The use of two different GPIO ports was mostly for routing reasons. The board is only 19mm × 48mm, after all.

[Volutar]

Sorry for making comment in this (closed) issue, but I think this question doesn't deserve its own, and practically related to this.

So question is:
Is it possible to rewire blue pill differently (according microcontroller pin reassignment), to minimize "dupont wiring", so it will be possible to adjust STM32 firmware?
To something like this:

Currently it looks randomish... And making GW "that" will definately ease wiring alot, and make whole hw setup less messy.

[drdpj]

You need to see which pins are 5V tolerant... Not all of them are!

…

On Tue, 5 Nov 2019, 22:29 Volutar, ***@***.***> wrote: Sorry for making comment in this (closed) issue, but I think this question doesn't deserve its own, and practically related to this. So question is: Is it possible to rewire blue pill differently (according microcontroller pin reassigning), to minimize "dupont wiring", so it will be possible to adjust STM32 firmware? To something like this: [image: image] <https://user-images.githubusercontent.com/3478087/68251359-c8829a80-0044-11ea-83ac-58d91c769d5a.png> Currently it looks randomish... And making GW "that" will definately ease wiring alot. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#4>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AATU2PF4INXKGBB46GQEAVDQSHXV5ANCNFSM4JIRJQLQ> .

[Volutar]

You need to see which pins are 5V tolerant... Not all of them are!

There is only one pin on this side of blue pill, which is not 5v tolerant - B5, and it's "not connected". We can unsolder this pin in the worst case (and probably this could be needed for 5.25", since they use pin 6 for Drive D).

[keirf]

A11 and A12 are USB. A9 and A10 are for serial (ie at least I use them!). It is not tenable long term to expect users to connect dirdct to the pill. Adapter boards will happen. They will be very cheap.

[Volutar]

Well, it’s a bummer. While A9/A10 can get some workaround, A11/A12 are not usable :(
People with dozen of disks to capture hardly gonna order adapter boards. I’m sure >90% of users are not longterm (and even if longterm, tend to be more sporadical), and will use temporary mishmashed dupont cable setup (and already using it). So at least some wire rearrangement ( in order to lessen crossing) would be appreciated.
Thanks for the answer!

[keirf]

Those people will just have to put up with a slight Dupont mishmash to save a couple of quid. It's not actually that bad anyway.

[dwillmore]

Could A8/A9 be used for the other drive select and motor signals?