“Good quality board and very useful features. I was really after the 8Mb external PSRAM for my project.
First problem for me was that there are commponents on the bottom of the PCB, which means flush fittoing to a PCB isn't possible. I don't think the Pimoroni Pico Plus 2 (PPP2) can be soldered to a PCB, which means that headers and a socket are needed to put i ton a PCB. This is usually fine, but caused me problems as I have a small amount of space above the Pico in my case. To solve this problem I used some copper pins that I made to hold the PPP2 to my PCB. These allow the Pico to be removed and a different one plugged in if necessary. Or they can be soldered and then if the PPP2 needs to be removed the pin can be cut and desoldered,
The Pico SDK does have a PPP2 board type as standard, but oddly, other than defining the CS pin for the PSRAM IC it doesn't enable the extra RAM.
I added this to my main() function:
// Pico2 external memory
gpio_set_function(PIMORONI_PICO_PLUS2_PSRAM_CS_PIN, GPIO_FUNC_XIP_CS1); // CS for PSRAM
xip_ctrl_hw->ctrl|=XIP_CTRL_WRITABLE_M1_BITS;
Then, adding a section in the Pico SDK for the PSRAM:
In this file:
./src/rp2_common/pico_crt0/rp2350/memmap_default.ld
Add the PSRAM section after the flash_end section:
.flash_end : {
KEEP(*(.embedded_end_block*))
PROVIDE(__flash_binary_end = .);
} > FLASH =0xaa
.psram (NOLOAD): {
. = ALIGN(4);
*(.psram*)
} > PSRAM
Define a macro:
#define PSRAM __attribute__((section(".psram.")))
Then, you can add PSRAM as a section attribute to objects:
VAR_INFO local_info[NOPL_MAX_LOCAL] PSRAM;
It would have been nice if this had been in the SDK, or there was similar information on the Pimoroni site.
I've also had to remove the connectors on the PPP2 as they took up too much vertical space. I do have the PPP2 in my project now, and the PSRAM seems to be working. So far I'm quite pleased, apart from the above. Need to get my code working now...”
“Love the led on the board it's more vibrant, and i never thought i would say this but the storage feels massive "16MB"
you guys did a great job with the White Text on the Board very visible to see makes it very easy to find the right GPIO.
Overall it's like the premium/PRO version versus the original pico 2 :D”
“For everyone else thats as bad as I am at spotting whats not there, let me just say
** No mounting holes **
Oops. Now I have to solder it in, I cannot use sockets as my application is on something that vibrates. Not mechanically interchangable after all.
Appart from that yeh, its great. Corrects all the stupid decisions Raspberry Pi made, chief amonst which for me was fitting the debug port connector.”
