Datasheet

Table Of Contents
USB PICOBOOT bootloader interface for advanced management.
Routines for programming and manipulating the external flash.
Fast floating point library.
Fast bit counting / manipulation functions.
Fast memory fill / copy functions.
Bootrom Source Code
The full source for the RP2040 bootrom can be found at https://github.com/raspberrypi/pico-bootrom.
This includes both version 1 and version 2 of the bootrom, which correspond to the B0 and B1 silicon
revisions, respectively.
2.8.1. Processor Controlled Boot Sequence
A flow diagram of the boot sequence is given in Figure 15.
Figure 15. RP2040
Boot Sequence
After the hardware controlled boot sequence described in Section 2.7, the processor controlled boot sequence starts:
Reset to both processors released: both enter ROM at same location
Processors check SIO.CPUID
Processor 1 goes to sleep (WFE with SCR.SLEEPDEEP enabled) and remains asleep until woken by user code,
via the mailbox
Processor 0 continues executing from ROM
If power up event was from Rescue DP, clear this flag and halt immediately
RP2040 Datasheet
2.8. Bootrom 157