I like the RP2040 • Hacker News Board

Re: I like the RP2040

#21

Post by HyulianGrader » Tue, Jun 11, 2024, 2:37 PM UTC

sshine wrote: post #14

orlp wrote: post #8

Earlier quoted context omitted.

The bootloader is read-only. What the bootloader loads isn't. If the thing you're trying to boot into is faulty, it doesn't matter because you can just replace the thing the bootloader is trying to load. If the bootloader itself was faulty, the device would be bricked.

To elaborate on the alternative: When the bootloader is not read-only, you can upload another bootloader. This is great in a different way because custom bootloaders allow for more flexibility. For example, you may want to keep two copies of your firmware on the chip: One that you're uploading, and one you can fall back to if the most recent one has problems. This protects you against failure during firmware upload o…

Nobody in their right mind is updating a bootloader in the field OTA, let alone one inaccessible on a mountain top.

Re: I like the RP2040

#22

Post by jsheard » Tue, Jun 11, 2024, 2:38 PM UTC

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.

Things like battery life will probably improve with experience, I was talking to a silicon guy about the RP2040 and they said it's pretty characteristic of a first generation design. The digital logic that can be validated on an FPGA is fine for the most part, but the analog elements are much more difficult to fine tune, hence the poor power consumption, poor ADCs, and lack of internal DACs or opamps in the RP2040, and why the Pico Ws radio is a separate off-the-shelf part rather than fully integrated like it is on the ESP32.

Re: I like the RP2040

#23

Post by tiku » Tue, Jun 11, 2024, 2:39 PM UTC

My Switch is unlocked by a rp2040. A lot of devices could be modded with it, given the size etc.

Re: I like the RP2040

#24

Post by eulgro » Tue, Jun 11, 2024, 2:39 PM UTC

Havoc wrote: post #18

How are people using this in practice? I’ve never worked with a BGA device. I’m guessing you need to design a board send it to say pcbway and then have the equipment to solder the bga in?

It's not a BGA, it's a QFN with a ground pad.

Re: I like the RP2040

#25

Post by axoltl » Tue, Jun 11, 2024, 2:41 PM UTC

"(This is the same microcontroller, just two bugfix revisions.)"

It is exactly the same microcontroller! They're just two different packaging options. One is a 7" reel with 500 units the other is a 13" reel with 3400 units. (See "Ordering code" in the datasheet (https://datasheets.raspberrypi.com/rp2040/rp2040-datasheet.p...))

Re: I like the RP2040

#26

Post by jrockway » Tue, Jun 11, 2024, 2:41 PM UTC

seba_dos1 wrote: post #20

ndiddy wrote: post #9

Earlier quoted context omitted.

He's saying that the bootloader is in ROM so it's unbrickable, but the application code that the bootloader jumps into can be updated over USB. Most mid-range and higher microcontrollers have a similar feature, but they almost always have a custom protocol that requires a specialized flashing program rather than showing up as a mass storage device.

To be frank, I don't get its appeal at all. Most hobbyist uCs were already unbrickable, and using mass storage mode for flashing is rather cumbersome and clunky to automate as soon as you're past hello worlds.

I've never had great luck with the mass storage flashing. It works fine, but boy is it slow. I bought a J-Link a few years ago and haven't looked back.

(It just takes a long time for the OS to recognize a USB device. And you have to press the reset button yourself in order to enter the bootloader. With something like J-Link, your build script can handle pressing the reset button and sending the code, saving you quite a bit of time between iterations.)

Re: I like the RP2040

#27

Post by kj4ips » Tue, Jun 11, 2024, 2:42 PM UTC

hitekker wrote: post #10

cide1 wrote: post #3

The lack of security features really limits where this can be used in commercial designs.

Can you explain how? Genuinely curious. The author only refers to "security theater" which seems to be when a product or system around a product makes people feel like they're safer, when actually it's not making anything more safer or more secure. https://en.wikipedia.org/wiki/Security_theater

I suspect this mostly refers to "Code Protect" or similar functions, that are designed to stop the user for extracting the firmware from a device in the field. Typically, when this is enabled, large parts of the debug interface stop working, and turning it off requires a "secure" erase, that clears the loaded firmware.

While many CP implementations are flawed, or can be bypassed by a skilled attacker (power glitching, &c), I wouldn't say they are purely theater, as they raise the required investment from a <$10 ISP to $$$+ for something like a chipwhisperer.

Re: I like the RP2040

#28

Post by neilo40 » Tue, Jun 11, 2024, 2:42 PM UTC

Havoc wrote: post #18

How are people using this in practice? I’ve never worked with a BGA device. I’m guessing you need to design a board send it to say pcbway and then have the equipment to solder the bga in?

Although it looks like BGA, it actually uses a QFN package where all the contacts are accessible at the edge. With a little practice they are relatively easy to hand solder (I've done many, not just rp2040)

Re: I like the RP2040

#29

Post by GlibMonkeyDeath » Tue, Jun 11, 2024, 2:44 PM UTC

Havoc wrote: post #18

How are people using this in practice? I’ve never worked with a BGA device. I’m guessing you need to design a board send it to say pcbway and then have the equipment to solder the bga in?

Almost universally a hobbyist would purchase the RP2040 mounted to a pcb with other i/o components (e.g. the Seeeduino Xiao https://wiki.seeedstudio.com/XIAO-RP2040/) There are other versions which bring out more lines to accessible solder points.

Of course you can design your own custom board, but I'd wager most people don't need or want to do this.

Re: I like the RP2040

#30

Post by em3rgent0rdr » Tue, Jun 11, 2024, 2:46 PM UTC

HyulianGrader wrote: post #12

nit: There are 6 different espressif microcontrollers in that table, not "dozens". Espressif also went many years with only the ESP8266, then many years more after introducing the ESP32 before this recent binge of releasing a new series every time they blink. ESP-IDF is really suffering for it, so I hope Raspberry avoid this fate or at least find a better way to support them all.

Considering how many different Raspberry Pis are out there now, I wouldn't be surprised if the Raspberry Foundation makes a plethora of newer microcontrollers.