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I like the RP2040

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Re: I like the RP2040

#261

Post by antirez »

mardifoufs wrote: post #243
antirez wrote: post #15

I switched from ESP32 to the RP2040 because it's a much more reliable and documented device. My only concern right now with the RP2040 is that there are many ESP32 models with SPIRAM but it's not so simple to find a SPIRAM equipped RP2040 board. To be honest, given that the C development environment of the RP2040 is so good, you can make good use of the memory, but when one wants to develop a large MicroPython projec…

Did you use esp-idf? Or the Arduino libs?

ESP-IDF, Arduino IDE is untouchable for serious stuff IMHO.

Re: I like the RP2040

#262

Post by boznz »

MegaDeKay wrote: post #17

The PIO's really are the star of the RP2040 show, giving it a capability that competing chips like the ESP32 can't match. They are appearing all over the place in the console hacking space for this reason. Lower power consumption in steep modes for battery-backed applications would be a welcome addition in any V2 version though.

Availability is the star of the show for me. One IC, long product lifetime, always in stock, after the shitshow that was 2021/2022 I'm not going to bother trying to shave a few cents to compromise this again.

Re: I like the RP2040

#263

Post by samatman »

JohnFen wrote: post #106

The RP2040 is pretty cool. I've used them in a half dozen projects now. > Raspberry Pi pulled a Henry Ford and boldly went with just one microcontroller. However, this one size fits all thing doesn't work for me. I prefer to use the least microcontroller that will do the job I need done. > There is no choice, no right sizing, but that might be OK! An RP2040 costs ~70 cents, and not all gizmos are produced by the mill…

A much larger pool of online documentation, example code, and experienced hobbyists who like answering questions, is worth a great deal more than eighty cents.

Getting more use out of the battery is a good and sufficient reason to use a less powerful controller, though. It being cheaper is nice in theory, but almost meaningless for a one-off project, in practice. I can't remember the last time I made a purchase which was a fraction of a dollar, it just doesn't move the needle.

Re: I like the RP2040

#264

Post by [deleted] »

kragen wrote: post #258
jvanderbot wrote: post #250

Earlier quoted context omitted.

You're making a probabilistic argument against the existence of an American made (or designed) equivalent to a Wifi+MCU module on a chip?

how is america in any way relevant here? we were discussing china you might be able to find american-designed (or european-designed, african-designed, antarctica-designed, etc.) chips that do something similar, but you can be pretty sure they will be made either in taiwan or in the rest of china in a now-deleted response to this comment, you asked, 'How is it relevant in the thread I started by asking for american de…

[deleted]

Re: I like the RP2040

#265

Post by petsfed »

peteforde wrote: post #161
crote wrote: post #157

Earlier quoted context omitted.

> The RP2040 requires careful placement of about a dozen components, including a crystal. To be fair, the chip is designed to make these really easy to place. There's pretty much one single layout which makes sense, and it provides easy access to all the pins you could possibly want. Combine that with the excellent documentation they have provided, and it's essentially just a multi-part drop-in design you don't ever…

You're kind of making my point for me; when every engineer has to place a dozen components, a non-zero number of them are going to make facepalm mistakes. Even if you create a sub-module layout that you include in every project you work on... that's still n slightly different permutations of the same thing, even if they are all perfect. (They aren't.)

A non-zero number of engineers will implement "hello world" wrong when they're first learning a language. That's not an argument against any given programming language either. "I made a design error that the documentation specifically calls out as something to avoid" doesn't hold much water as a legitimate criticism. Especially when the design error is "I didn't put the decoupling cap very close to the pin it's supposed to be decoupling for". (as an aside, you should read the "minimal design example" chapter from the RP2040 Hardware Design Guide[0], even if you have zero intention of designing with the chip. It's a literal masterclass in beginner-level pcb design.)

Literally none of this is actually a hazard if you design more than one PCBA with a microcontroller on it in your entire life. I'd argue that designing around a castellated-edge module is much MUCH harder to get right on the first try than discrete components, even though the parameter space is apparently much smaller.

0. https://datasheets.raspberrypi.com/rp2040/hardware-design-wi...

Re: I like the RP2040

#266

Post by jvanderbot »

kragen wrote: post #258
jvanderbot wrote: post #250

Earlier quoted context omitted.

You're making a probabilistic argument against the existence of an American made (or designed) equivalent to a Wifi+MCU module on a chip?

how is america in any way relevant here? we were discussing china you might be able to find american-designed (or european-designed, african-designed, antarctica-designed, etc.) chips that do something similar, but you can be pretty sure they will be made either in taiwan or in the rest of china in a now-deleted response to this comment, you asked, 'How is it relevant in the thread I started by asking for american de…

That's very helpful.

Re: I like the RP2040

#267

Post by fleventynine »

kragen wrote: post #214
fleventynine wrote: post #118

Earlier quoted context omitted.

As I see it, if you need everything to run on a single cpu core, the alternatives are to either implement threads (wasting memory on redundant stacks) or to write the event-driven state machines manually. Whether the state machine is pumped by interrupts or not doesn't change anything IMHO. Because of RAM constraints, all the bare-metal projects I've worked on have used manually-written state machines, and I'm comfor…

none of this will be news to you , but it's probably of interest to other people reading the discussion. you can do stuff inside the interrupt handler itself, and while what you do there does have to be an event-driven explicit state machine, interrupts introduce two key differences: - the rest of your program doesn't have to be an explicit state machine; it can use structured control flow with nested loops and condi…

> the rest of your program doesn't have to be an explicit state machine; it can use structured control flow with nested loops and conditionals and subroutines

This works well until the requirements change and you have to run two structured control flows simultaneously. If I find myself in such a situation and have no SRAM for a second thread, rust async may be the quickest way to accomplish the goal without a major rewrite into manual event driven code.

Re: I like the RP2040

#268

Post by Johanx64 »

jayyhu wrote: post #254
vardump wrote: post #248

Earlier quoted context omitted.

> There are many options for other MCUs, that compare favorably to with RP2040 That's pretty interesting, could you list some?

The STM32 F0/G0/C0 lines come to mind. More I/O, more peripherals and built-in flash. For hobbyist levels, buying 1-10 pcs they are comparable in price to an RP2040 + SPI flash. However at volume pricing, the STM32 MCU's can be cheaper than just the RP2040 itself. I do think Raspberry Pi needs to figure out volume pricing if they want to be competitive for anything that's not just hobbyists.

rp2040 is 64cents @ 1000qty, thats a good price, compatible winbond 16mbit flash is 12cents.

You need to go up way above a dollar to get comparable specs, given the unique nature of rp2040, two cores with fairly high clock, 264kb sram, pio.

The only thing i dont like about rp2040 is the package, not hobbyist home soldering friendly for custom board designs.

Re: I like the RP2040

#269

Post by nkozyra »

MegaDeKay wrote: post #17

The PIO's really are the star of the RP2040 show, giving it a capability that competing chips like the ESP32 can't match. They are appearing all over the place in the console hacking space for this reason. Lower power consumption in steep modes for battery-backed applications would be a welcome addition in any V2 version though.

Don't cycle sleeps help on the esp32? I typically run on power but I know a lot of people get all day with wifi on reasonable LiPo

Re: I like the RP2040

#270

Post by moffkalast »

Teknoman117 wrote: post #246
moffkalast wrote: post #95

Earlier quoted context omitted.

Ditto for robotics. 8 PIO units are enough to read and log four quadrature encoders at practically no interrupt cost, so it's possible to build a perfectly performant closed loop controller in something as slow as Micropython.

You don't even need the 8 :), 4 quadrature inputs will fit on one PIO block. Some lovely person got a quadrature decoder into 24 instructions, so you can potentially still do something useful on the same PIO block if you only need one or two quadrature encoders.

I mean yeah one block is 8 units right? Two pins per encoder which both need a unit each.
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