Re: F2FS On USB Sticks?

On 25/03/2025 05:18, c186282 wrote:

On 3/24/25 7:31 AM, The Natural Philosopher wrote:

On 23/03/2025 10:05, c186282 wrote:

On 3/22/25 8:52 PM, The Natural Philosopher wrote:

On 22/03/2025 19:09, rbowman wrote:

On Sat, 22 Mar 2025 13:35:54 +0000, The Natural Philosopher wrote:
>

The PICO has no filesystem. IN use you hold a button down while powering
up and it's Flash presents itself as a USB drive. You copy a special
binary file of compiled code onto that 'drive', and it reboots and runs
it..

>
Okay, you hold down BOOTSEL when plugging it into the USB. Then it shows
up on Files as RP2350.  If you click on that you see INDEX.HTM and
INFO_UF2.TXT. If you look at Properties it reports 2 items totaling 305
bytes and 134.1 MB free.
>
df -Th /dev/sda1
Filesystem     Type  Size  Used Avail Use% Mounted on
/dev/sda1      vfat  128M  8.0K  128M   1% /media/xxxxx/RP2350
>
Then you can
>
cp blink.uf2 /media/xxxxx/RP2350/
>
and, lo and behold, it starts blinking and vanishes from the file system!
I'm lazy so after it blinks 20 times it calls
>
reset_usb_boot(0, 0);
>
and miraculously reappears mounted.  How does it do all this without a
file system known to Ubuntu? I won't even ask why after copying the
CircuitPython uf2 it reboots mounted as CIRCUITPYTHON and you can copy .py
files directly.
>
My comment had nothing to do with the programmatic use of the flash
memory, only how the Pico presents as a mass storage device.

>
Well it spoofs the disk obviously

>
   Ya know ..... think I'm gonna stay away from Pico's  :-)
>

It is a big learning curve. But they are fearfully cheap...small...and light
>

   If I want microcontrollers, there are more traditional
   straight-up boards out there. If I want microprocessors
   there are the straight-up PIs and beyond.
>
   Did use PICs for a long time ... kinda remember their
   quirks and tricks. There are Pico/Nano style boards to
   be had cheap that use PICs. Atmel versions also exist.

>
I looked at those. Many times the price of a pico.
>
I am slowly making up libraries of Code That Works (as opposed to what you find plastered around the Web.

    As I was talking about elsewhere, there's the price
   of the target CHIPS, and then the price of the
   development system/board. The price of the latter
   has become rather high in some cases ... can't even
   get a good all-purpose PIC programmer anymore that
   doesn't require special sockets/libs and such for $$$
 

?. Picos don't need development boards, I mean what are you going to hang round them that is so complex? I just go straight to the final PCB.
Works out at maybe $20 for 10 chinese made PCBs...

   MicroChip USED to sell a very useful serial appliance
   with a 40-pin ZIF socket. Upgraded it once. You could
   stick a large variety of their chips into the thing.
   Just specify in their dev app and it'd all work well.
    But now .........
    If you are an 'experimenter' or small-run person then
   the price of the dev/programming crap kinda now makes
   it just TOO.
 

?/ What???  The point about a PICO is that it *is* a development board, if you like, It's all in for $5.
All youi need is s computer running a GCC cross compiler and the free development envir9nmenmt

   Found people long back who sold an upgraded 8051 (it
   was 'fat', had an actual battery in the case to keep
   the RAM alive) AND a BASIC-like compiler. The programmer
   was a small, kinda bare, PC board - again serial interface.
   Not fancy at all - but GOT IT DONE. Made dozens of devices
   using that all for almost nothing.
    Oh, if a MHz or so is enough, the 8051 is STILL a great chip.
 

That must have been 50 years ago., Things have moved on

   In any case, I *understand* the Pico/Nano approach. It's
   "all in one" and no vast other investment required. As
   for whether they're good/easy for EVERYTHING, well ....
   actually ARDs are still competitive, esp for low-power
   applications. Sleep the thing and wait for the next
   interrupt ........
 

PICOS essentially the same. Or what I am looking to do is to use an external  ultra low power timer to switch the board on after a long delay, and the board switches  itself off when its done its business. Rinse and repeat
--
The urge to save humanity is almost always a false front for the urge to rule.
– H. L. Mencken, American journalist, 1880-1956