[sdiy] Xpander (was: Re: Moog Memorymoog clone almost completed)

[Brian Willoughby]

On Oct 18, 2020, at 12:17 PM, charlie <charlie at finitemonkeys.com> wrote:
>> Maybe not $2, but Microchip offers PIC24FJ chips with USB for about US$3.
> 
> the LPC11U24FHI33 is < $2 , allwinner a13 is $1 in quantity , also
> software usb stack is obviously available for much less, but that's
> cheating.

I wouldn't call it cheating, but it's certainly a waste of energy to perform USB in software rather than with a hardware peripheral.

The real catch is that software USB can only operate at Low Speed, while USB-MIDI is a Full Speed Class. I doubt you'll find any software USB that talks USB-MIDI to a standard Host driver. So, the context of a synth controller rules out software USB. Besides, there's likely no CPU left when performing software USB, even at Low Speed.


The NXP Cortex-M0 ARM looks promising, though. Thanks for the heads up. I enjoyed working with the Freescale ColdFire (v2) because it brought me back to the Classic Mac M68000 days, and NXP ended up buying Freescale Semiconductor so I know a few of the folks that survived the transition.

Brian