pico_multicore

Adds support for running code on, and interacting with the second processor core (core 1). More...

Modules
	fifo
	Functions for the inter-core FIFOs.
	doorbell
	Functions related to doorbells which a core can use to raise IRQs on itself or the other core.
	lockout
	Functions to enable one core to force the other core to pause execution in a known state.

Macros
#define	SIO_FIFO_IRQ_NUM(core)
	Returns the irq_num_t for the FIFO IRQ on the given core. More...

Functions
void	multicore_reset_core1 (void)
	Reset core 1. More...
void	multicore_launch_core1 (void(*entry)(void))
	Run code on core 1. More...
void	multicore_launch_core1_with_stack (void(*entry)(void), uint32_t *stack_bottom, size_t stack_size_bytes)
	Launch code on core 1 with stack. More...
void	multicore_launch_core1_raw (void(*entry)(void), uint32_t *sp, uint32_t vector_table)
	Launch code on core 1 with no stack protection. More...

Detailed Description

Adds support for running code on, and interacting with the second processor core (core 1).

Example

 
#include <stdio.h>
#include "pico/stdlib.h"
#include "pico/multicore.h"
 
#define FLAG_VALUE 123
 
void core1_entry() {
 
    multicore_fifo_push_blocking(FLAG_VALUE);
 
    uint32_t g = multicore_fifo_pop_blocking();
 
    if (g != FLAG_VALUE)
        printf("Hmm, that's not right on core 1!\n");
    else
        printf("Its all gone well on core 1!");
 
    while (1)
        tight_loop_contents();
}
 
int main() {
    stdio_init_all();
    printf("Hello, multicore!\n");
 
 
    multicore_launch_core1(core1_entry);
 
    // Wait for it to start up
 
    uint32_t g = multicore_fifo_pop_blocking();
 
    if (g != FLAG_VALUE)
        printf("Hmm, that's not right on core 0!\n");
    else {
        multicore_fifo_push_blocking(FLAG_VALUE);
        printf("It's all gone well on core 0!");
    }
 
}

Macro Definition Documentation

SIO_FIFO_IRQ_NUM

#define SIO_FIFO_IRQ_NUM

(

core

)

Returns the irq_num_t for the FIFO IRQ on the given core.

On RP2040 each core has a different IRQ number: SIO_IRQ_PROC0 and SIO_IRQ_PROC1. On RP2350 both cores share the same irq number (SIO_IRQ_PROC) just with a different SIO interrupt output routed to that IRQ input on each core.

Note this macro is intended to resolve at compile time, and does no parameter checking

Function Documentation

multicore_launch_core1()

void multicore_launch_core1

(

void(*)(void)

entry

)

Run code on core 1.

Wake up (a previously reset) core 1 and enter the given function on core 1 using the default core 1 stack (below core 0 stack).

core 1 must previously have been reset either as a result of a system reset or by calling multicore_reset_core1

core 1 will use the same vector table as core 0

Parameters

entry

Function entry point

See also

multicore_reset_core1

multicore_launch_core1_raw()

void multicore_launch_core1_raw	(	void(*)(void)	entry,
		uint32_t *	sp,
		uint32_t	vector_table
	)

Launch code on core 1 with no stack protection.

Wake up (a previously reset) core 1 and start it executing with a specific entry point, stack pointer and vector table.

This is a low level function that does not provide a stack guard even if USE_STACK_GUARDS is defined

core 1 must previously have been reset either as a result of a system reset or by calling multicore_reset_core1

Parameters

entry	Function entry point
sp	Pointer to the top of the core 1 stack
vector_table	address of the vector table to use for core 1

See also

multicore_reset_core1

multicore_launch_core1_with_stack()

void multicore_launch_core1_with_stack	(	void(*)(void)	entry,
		uint32_t *	stack_bottom,
		size_t	stack_size_bytes
	)

Launch code on core 1 with stack.

Wake up (a previously reset) core 1 and enter the given function on core 1 using the passed stack for core 1

core 1 must previously have been reset either as a result of a system reset or by calling multicore_reset_core1

core 1 will use the same vector table as core 0

Parameters

entry	Function entry point
stack_bottom	The bottom (lowest address) of the stack
stack_size_bytes	The size of the stack in bytes (must be a multiple of 4)

See also

multicore_reset_core1

multicore_reset_core1()

void multicore_reset_core1

(

void

)

Reset core 1.

This function can be used to reset core 1 into its initial state (ready for launching code against via multicore_launch_core1 and similar methods)

Note

this function should only be called from core 0