Feature: RP2350 A and B variant

[earlephilhower]

Discussed in #2371

^{Originally posted by elral August 26, 2024}
The new RP2350 is available in variant A and B. The A variant has the same number of pins as the RP2040 where the B variant has 40 pins (and at least the analog pins on another pins).
For now there is one generic variant for the RP2350. I am wondering if it would make sense to mark this variant as A and setup another one for variant B.

Yesterday I moved our project from platformIO to the Arduino IDE to test it with the RP2350. For what I could test everything was working fine (except AnaologIn as I am using an PGA2350, but will test it with a Pico2 again).
Really great job!! Thanks a lot for your effort!

[earlephilhower]

A quick look through the SDK seems to indicate there is no actual SDK difference between the two. So, only one rp2350/libpico.a needed. Only real ugly bit will be the PIO GPIOBASE conversion which does GPIO shifting on a per-PIO (not SM or program) basis. Need to modify PIOProgram to be aware of the and manage it...

[earlephilhower]

#2433 has support for the B variant, tracking there

[earlephilhower]

Closed w/#2433.