The Raspberry PI PICO 2, now has extra RISC-V cores

[iMo]

Interesting. While it may have little practical value, being able to run an ARM core alongside a RISC-V core has potentially some educational value.

I think the dual ARM and RV has not been a good decision..
99% of the mainstream pico users do not care, they want to run their programs architecture regardless (see for example above the testing approach of the mysterious 2350 tester when he did not mess with the RV either).

..For RISC-V lovers there are also some RISC-V cores to play with, but I do like my Cortex-M33s, so I’ve been sticking to those. The RAM size is doubled!..

Instead waisting silicon they had to focus on improving or adding some new features (a long list)..
So either ARM or RV..

[tszaboo]

I think the dual ARM and RV has not been a good decision..
99% of the mainstream pico users do not care, they want to run their programs architecture regardless (see for example above the testing approach of the mysterious 2350 tester when he did not mess with the RV either).

If they want to continue with RV in the future, they need to port the ecosystem to RV. This means Mciropython, Circuitpython, RTOSes, and any other resources need to work with RV. If you only have developer chips, that's a chicken and egg problem, since as you said, most people are not interested, so no work would be done on the RV ports.. This way they can ship eggs together with the chicken, so hopefully hackers will start using it, and porting.
And since the peripherals are the same, this could hopefully be a very smooth transition.

[Andree Henkel]

The weak point for my applications that will lead to selct a µC of competition is still lack of internal DAC´s
I don´t at all mind to have to connect external flash.

but as soon as I would have to use external DAC´s, Competitor with integrated DAC will have cost advantages.
And no, I won´t go into the hassle of PWM DAC or improvised DAC using R-Networks and several GPIO outputs

nice that the large chiip now has 8 ADC
but it would be much appreciated if small chip had 2 DAC and large one 4 DAC, 10Bit would ne reasonably enough, but 12 Bit would be a nice to have

[rteodor]

Instead waisting silicon they had to focus on improving or adding some new features (a long list)..
So either ARM or RV..

This might be some manager being cautious on licensing (fees): Look ARM, if you don't behave RISC-V is waiting behind that door ready to work for cheap!

In fact this seems to be the industry trend: RISC-V has a level of support that looks unusually high compared to any other previous arch. If I was looking for a political answer I would ask from where is this support coming? And why?

[MK14]

It will be very interesting, to compare the execution time, power consumption, code size and perhaps other things.  By recompiling the same project, between the Arm M33F cores and the RISC-V cores.

Most systems/MCUs, don't let you do that.  I.e. Not using exactly the same MCU, and just rebooting into the other CPU type, and recompiling the GCC code, and any other changes that need to be made, between the project types.

Also, according to the datasheet, at least one of the RISC-V features (related to what is usually used as a 1 microsecond timer/time signal for RISC-V), is available for both the RISC-V and Arm M33F modes.

EDIT:
Added quote from datasheet:

3.1.8. RISC-V Platform Timer
This 64-bit timer is a standard peripheral described in the RISC-V privileged specification, usable equally by the Arm and
RISC-V processors on RP2350

[coppice]

The weak point for my applications that will lead to selct a µC of competition is still lack of internal DAC´s
I don´t at all mind to have to connect external flash.

but as soon as I would have to use external DAC´s, Competitor with integrated DAC will have cost advantages.
And no, I won´t go into the hassle of PWM DAC or improvised DAC using R-Networks and several GPIO outputs

nice that the large chiip now has 8 ADC
but it would be much appreciated if small chip had 2 DAC and large one 4 DAC, 10Bit would ne reasonably enough, but 12 Bit would be a nice to have

If you look around the MCU market only a small proportion of available parts have a DAC in them, and they are often not big sellers. If you need a DAC you are looking in at a fairly niche market, and that always means most products are not right for you.

[langwadt]

Instead waisting silicon they had to focus on improving or adding some new features (a long list)..
So either ARM or RV..

compared to the large RAM,peripherals, PIOs, and regulator, the area of the extra cores are probably insignificant

[NickAmes]

I'm impressed by the new features, but it's a shame that there's still no input capture functionality. (Maybe the new PIO features enable that? Haven't looked into those yet.)

The switching regulator seems odd. In Hardware Design with RP2350 (pg. 6), there's a defensive-sounding paragraph about how physics is hard, followed by a strong recommendation to use only their custom-wound inductor. I've used a few microcontrollers that included buck regulators, and none of them needed that. (Although their current output was in the 20-50mA ballpark, not 200mA as in the RP2350.) Has anyone seen that before?

[josip]

The weak point for my applications that will lead to selct a µC of competition is still lack of internal DAC´s
I don´t at all mind to have to connect external flash.

but as soon as I would have to use external DAC´s, Competitor with integrated DAC will have cost advantages.
And no, I won´t go into the hassle of PWM DAC or improvised DAC using R-Networks and several GPIO outputs

nice that the large chiip now has 8 ADC
but it would be much appreciated if small chip had 2 DAC and large one 4 DAC, 10Bit would ne reasonably enough, but 12 Bit would be a nice to have

With internal DAC and USB device without external crystal, form me it will be almost perfect. I see in datasheet that 64 gpio bits / pins can be written in one cpu cycle. With 64 gpio's and less VDIO decap (I guess that they keep the same pinout because of compatibility with rp2040) pins totally perfect. I don't need more than 2MB of flash so RP2354B is the right one.

If you look around the MCU market only a small proportion of available parts have a DAC in them, and they are often not big sellers. If you need a DAC you are looking in at a fairly niche market, and that always means most products are not right for you.

NXP / Kinetis entry level K32L2B are with DAC. I also found other low cost Cortex-M devices from other vendors (I searched for it) that have DAC.

[Nominal Animal]

No high-speed USB 2.0 (480 Mbit/s) is very limiting, in my opinion.  12 Mbit/s, or about 1 Mbytes/second of data payload, just doesn't cut it for many of my needs with this kind of computing power.

[ataradov]

With their apparent signal integrity issues/concerns, I would not expect USB HS any time soon. USB 2.0 PHY takes up a lot of silicon area and really tricky from signal integrity point of view. Even big vendors with a lot of design experience struggle with it.

[coppice]

If you look around the MCU market only a small proportion of available parts have a DAC in them, and they are often not big sellers. If you need a DAC you are looking in at a fairly niche market, and that always means most products are not right for you.

NXP / Kinetis entry level K32L2B are with DAC. I also found other low cost Cortex-M devices from other vendors (I searched for it) that have DAC.

And if you find the application those chips were designed for you'll know why the DAC is there, and why its spec is what it is. If you look around most MCU ranges you'll find one or two parts with a DAC or two, especially of the line includes parts with op amps, and other analogue signal conditioning modules. Its generally just a couple, though, and there will have a spec specific to the applications which drove the module to be included. MCUs are NOT general purpose products.

[langwadt]

imagine if ICs like the one used on this had some actually documentation, https://wiki.sipeed.com/hardware/en/maixzero/m0s/m0s.html

[zapta]

Platformio support of the PICO is limited because RPI do not pay for the support.

https://community.platformio.org/t/why-the-minimal-presence-of-rp2040-on-platformio/37600/4

[Arte]

I don't think anyone's expecting a USB HS PHY but one could hope for a ULPI which is considerably less demanding (60MHz signals).
In fact if it wasn't for the external USB PHY e.g USB3300 being the master of the comms channel and having the rights to interrupt comms and start talking within 2 cycles, PIOs on an overclocked rp2040 could maybe cut it...

[PCB.Wiz]

The weak point for my applications that will lead to selct a µC of competition is still lack of internal DAC´s
I don´t at all mind to have to connect external flash.

but as soon as I would have to use external DAC´s, Competitor with integrated DAC will have cost advantages.
And no, I won´t go into the hassle of PWM DAC or improvised DAC using R-Networks and several GPIO outputs

nice that the large chiip now has 8 ADC
but it would be much appreciated if small chip had 2 DAC and large one 4 DAC, 10Bit would ne reasonably enough, but 12 Bit would be a nice to have

In a core with that much high speed digital, a DAC would be compromised.  They are also not low-die-area items.
Best to just pick a small MCU that has the DAC mix you need, and pair it as an Analog focused peripheral ?

[Nominal Animal]

Platformio support of the PICO is limited because RPI do not pay for the support.

https://community.platformio.org/t/why-the-minimal-presence-of-rp2040-on-platformio/37600/4

The Raspberry Pi Foundation has never been interested in interacting with open source projects.  When they have to, they use temporary employees to do it.

[PCB.Wiz]

I'm impressed by the new features, but it's a shame that there's still no input capture functionality. (Maybe the new PIO features enable that? Haven't looked into those yet.)

Yes, PWMB allows gate and count inputs, but no capture input (plus registers are only 16b)  ?! 

There are reciprocal counter examples out there, on the RP2040, so the PIO can certainly manage capture.
Typically these use 3 state engines :

•   Define Nominal (minimum) Gate time using pin as flag, and sync to Fin edges.
•   Count Time during gate
•   Count cycles during gate

The PIO lacks wait edge, so code is forced to use two lines and run slower, and fatter 

[MT]

30 GPIO on a 60-pin device!?.. What!?

[ataradov]

They have a lot of power supplies and all special functions (USB/oscillators) are on dedicated pins. Plus external QSPI flash takes up 6 pins.

[SiliconWizard]

30 GPIO on a 60-pin device!?.. What!?

Or 48 GPIOs on a 80-pin device.

[boz]

What I am seeing is a well specified cheap and configurable microprocessor and can't wait to get my new dev board. I have used the RP2040 since early 2022 the PIO is amazing and can be programmed to fill in most of the gaps people her are whining about, for the new chip the only downside I can see is they dropped the RTC but everything else has improved.

Rather than listen to the doom mongers here who are heavily invested in their current ecosystems I would tell people to spend $5 and try it, the community is large and very friendly as everyone is a noob so you're not going to get some toss-pot greybeard telling you what a fuckwit you are for not knowing about some weird errata about an I2C clock stretching bug.

Shame I didn't sell my stash of STM32 and PIC chips while the prices were high.

[ataradov]

People are not "whining", but discussing objective downsides to the design. Everyone knows what PIO is and how good it is, there is nothing to discuss here.

As it is right now, this MCU is fine for hobby use, but it will not be suitable for a lot of commercial designs. And the new device does not address most of those concerns.

[floobydust]

Raspberry Pi did their IPO June 11, 2024 stock price kinda flat?
As always, investors want new new new so pressure to release something is high.

Why makers have to endure some political battle over two CPU types within the Pico 2 is beyond me. Is this a Dr. Jekyll and Mr. Hyde creation? Really.

Instead, pick one and give us some peripherals like Espressif generously does with the ESP32 which kicks ass off the Pico 2.

The magical unicorn PIO is nothing like a real TPU on Freescale or Infineon MCU's. People are happy with latency, hoop jumping serving the PIO, it doesn't even decr or is it increment anything? 9 op-codes? Oh they broke the silicon piggy bank with that lol. I'm unhappy that as an embedded MCU it misses basics that even 8-bit clunkers have.

[kamocat]

The switching regulator seems odd. In Hardware Design with RP2350 (pg. 6), there's a defensive-sounding paragraph about how physics is hard, followed by a strong recommendation to use only their custom-wound inductor. I've used a few microcontrollers that included buck regulators, and none of them needed that. (Although their current output was in the 20-50mA ballpark, not 200mA as in the RP2350.) Has anyone seen that before?

Using a custom inductor? No, I've never seen that. But some buck regulator datasheets show a capacitor in the feedback network to improve stability.
You can see it in the application circuit of my favorite buck converter AP63200 pg. 9