A new riser?

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sampedenawa
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Joined: Thu Mar 14, 2019 4:22 pm

Re: A new riser?

Post by sampedenawa » Wed Nov 06, 2019 2:37 pm

terriblefire wrote:
Wed Nov 06, 2019 2:17 pm
The main thing we'd want to do is to make this work for PC/USB joypads.. that should be possible without much hardware change at your side right?
Correct.
My only concern is about emulating CD32 joypads.
In order to be able to do that, I should strip out from the current hw at least one of the 3.3->5v level translation mosfets (so I can read the clk signal sent out by the console to the pad).
Easy and no risky at all mod (first hid2ami prototypes didn't have any mosfet at all), but a slightly less "clean" hw design.
Oh, incidentally I will then have to code CD32 pad emu in the fw ;)

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Re: A new riser?

Post by terriblefire » Wed Nov 06, 2019 6:56 pm

sampedenawa wrote:
Wed Nov 06, 2019 2:37 pm
Correct.
My only concern is about emulating CD32 joypads.
In order to be able to do that, I should strip out from the current hw at least one of the 3.3->5v level translation mosfets (so I can read the clk signal sent out by the console to the pad).
Easy and no risky at all mod (first hid2ami prototypes didn't have any mosfet at all), but a slightly less "clean" hw design.
Oh, incidentally I will then have to code CD32 pad emu in the fw ;)
Yeah. the fw is something i wanted to avoid doing.

Also the CD32 needs a hack to put the joystick on the riser.... maybe hack up one of your current boards to run joypads in the joystick port. Then when i clear the decks i'll get a a riser started and see if we cant put two of these plus a keyboard controller into the riser. I presume its easy to detect multiple HID devices in a single arm chip?
———
I get cranky when asked to repeat myself.

sampedenawa
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Joined: Thu Mar 14, 2019 4:22 pm

Re: A new riser?

Post by sampedenawa » Thu Nov 07, 2019 11:12 am

terriblefire wrote:
Wed Nov 06, 2019 6:56 pm
I presume its easy to detect multiple HID devices in a single arm chip?
Unfortunately the USB hardware stack of stm32f105 can bear one single HID device at a time, while in USB host mode (usb host mode not supported by the hardware).
So for two pads we should put two chips on board (luckily they are extremely cheap).
Further one could be added to manage the keyboard (I already have keyboard support in my current firmware)

It's no efficient at all, but it does not add too much circuit complexity, because only few pins of each chip shall be connected.

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Re: A new riser?

Post by terriblefire » Thu Nov 07, 2019 11:18 am

sampedenawa wrote:
Thu Nov 07, 2019 11:12 am
Unfortunately the USB hardware stack of stm32f105 can bear one single HID device at a time, while in USB host mode (usb host mode not supported by the hardware).
So for two pads we should put two chips on board (luckily they are extremely cheap).
Further one could be added to manage the keyboard (I already have keyboard support in my current firmware)

It's no efficient at all, but it does not add too much circuit complexity, because only few pins of each chip shall be connected.
Space is a serious constraint on the riser.. there isnt much room at all.. are there any ARM variants that can cope with 2 USB devices?

I'm also a little concerned about doing the mouse with 2 arm chips. Essentially the chip needs to not do the DAC and put the data on the data bus when requested instead. This needs more pins. The mouse analog lines are not present on the riser.
———
I get cranky when asked to repeat myself.

sampedenawa
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Re: A new riser?

Post by sampedenawa » Thu Nov 07, 2019 12:43 pm

Why talking about DACs ? Mouse lines aren't analog ... not sure what you are referring to ???
Original Amiga mice output "quadrature waveforms" on 2 differential line pairs (4 wires in total).
What Hid2AMi does (in the mouse part) is to translate the timed dataflow packets coming from HID mice into [digital] "quadrature waveforms"

Returning in topic: there's a stm32F412 and a guy on github who seems to have coded an USB-HUB firmware stub.
I could think about two scenarios:
either
a. try to port his work to stm32F105 (the fw stack could be the same)
or
b. port the current hid2ami fw to stm32F4xx


terriblefire wrote:
Thu Nov 07, 2019 11:18 am
sampedenawa wrote:
Thu Nov 07, 2019 11:12 am
Unfortunately the USB hardware stack of stm32f105 can bear one single HID device at a time, while in USB host mode (usb host mode not supported by the hardware).
So for two pads we should put two chips on board (luckily they are extremely cheap).
Further one could be added to manage the keyboard (I already have keyboard support in my current firmware)

It's no efficient at all, but it does not add too much circuit complexity, because only few pins of each chip shall be connected.
Space is a serious constraint on the riser.. there isnt much room at all.. are there any ARM variants that can cope with 2 USB devices?

I'm also a little concerned about doing the mouse with 2 arm chips. Essentially the chip needs to not do the DAC and put the data on the data bus when requested instead. This needs more pins. The mouse analog lines are not present on the riser.

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Re: A new riser?

Post by terriblefire » Thu Nov 07, 2019 12:51 pm

sampedenawa wrote:
Thu Nov 07, 2019 12:43 pm
Why talking about DACs ? Mouse lines aren't analog ... not sure what you are referring to ???
Original Amiga mice output "quadrature waveforms" on 2 differential line pairs (4 wires in total).
What Hid2AMi does (in the mouse part) is to translate the timed dataflow packets coming from HID mice into [digital] "quadrature waveforms"
Quad waveforms... i havent dug into them before but assumed they were analog. Mostly because Haynie got pissed when people ran those lines next to the databus on the original A2000 (i think). caused the mouse to jitter.

Either way you havent got those signals on the riser. You need to put a 16 bit wide data port on the riser that responds when the system accesses the mouse custom chip register... and supply the X/Y values directly.

There are also analog joystick signals but i guess nothing actually uses those. But they could have been used with joypads? maybe for a future thing... i always fancied hooking my G27 wheel up to F1GP on the amiga.

Returning in topic: there's a stm32F412 and a guy on github who seems to have coded an USB-HUB firmware stub.
I could think about two scenarios:
either
a. try to port his work to stm32F105 (the fw stack could be the same)
or
b. port the current hid2ami fw to stm32F4xx
Either may work. Probably should grab one of those and slap it on a riser to build a test rig to do the dev work.
———
I get cranky when asked to repeat myself.

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