⛅️ 🤲 ☝🏾 How to program multi-core microcontrollers 👩🏿‍🔬 🕴🏿 🈸

Over the past ten years, the processors in almost all of our devices have become multi-core. They are followed by multi-core microcontrollers. In the catalogs of major manufacturers, you can already find general-purpose microcontrollers with several cores at reasonable prices. So it looks like it's time to start using multi-core microcontrollers in your own devices. Naturally, in cases where it is justified.

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LPC55S69-EVK NXP LPC55S69, Cortex M33. IAR Embedded Workbench 8. , , . , .

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C: Project > Create New Project. C / main. , 0, . CPU0.
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General Options > Target .

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General Options > Library Configuration Use CMSIS.
(C/C++ Compiler > Preprocessor) : < SDK>\devices\LPC55S69. Defined symbols CPU_LPC55S69JBD100_cm33_core0 ( , ).
Linker > Config Override default LPC55S69_cm33_core0_flash.icf SDK ( < SDK>\devices\LPC55S69\iar).
Debugger > Setup (Driver) CMSIS DAP.
, Debugger > Download Verify Download Use flash loader(s).
system_LPC55S69_cm33_core0.c startup_LPC55S69_cm33_core0.s ( < SDK>\devices\LPC55S69 < SDK>\devices\LPC55S69\iar ). , .

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#include "LPC55S69_cm33_core0.h"

#define LED_GPIO_BLOCK 1
#define LED_GPIO_PIN 7

static inline void Delay(void)
{
 for(int i = 0; i < 8000000; i++);
}

int main()
{  
 /**** LED setup ****/
 // Enable clocking for GPIO1 (located on AHB bus)
 SYSCON->AHBCLKCTRLX[0] |= SYSCON_AHBCLKCTRL0_GPIO1_MASK;

 // Set direction for GPIO1 7 as output
 GPIO->DIR[LED_GPIO_BLOCK] |= GPIO_DIR_DIRP(1 << LED_GPIO_PIN);

 while(1)
 {
   /**** LED blinking ****/
   GPIO->B[LED_GPIO_BLOCK][LED_GPIO_PIN] = 0;  // Turn led On
   Delay();
   GPIO->B[LED_GPIO_BLOCK][LED_GPIO_PIN] = 1;  // Turn led off
   Delay();
 }
}

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#define LED_GPIO_PIN 7  -->  #define LED_GPIO_PIN 4

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// Sequence required to be written
// to SYSCON->CPUCTRL register ORed with other bits
// to applay settings
// See UM11126 4.5.70 for more details
#define SYSCON_CPUCTRL_ENABLING_SEQ 0xC0C40000

// Warning!!! IAR specific code. 
// core1_image_start is defined in 
// LPC55S69_cm33_core0_flash.icf linker config file
extern unsigned char core1_image_start[];
#define CORE1_IMAGE_START core1_image_start

main() 1:

/**** CPU1 (slave) setup ****/
// Enable CPU1
SYSCON->CPUCFG |= SYSCON_CPUCFG_CPU1ENABLE_MASK;

// Setup firmware boot address
SYSCON->CPBOOT = SYSCON_CPBOOT_CPBOOT(CORE1_IMAGE_START);

// Enable clock and reset CPU1
SYSCON->CPUCTRL = SYSCON->CPUCTRL | SYSCON_CPUCTRL_ENABLING_SEQ | 
                  SYSCON_CPUCTRL_CPU1RSTEN_MASK | SYSCON_CPUCTRL_CPU1CLKEN_MASK;

// Release reset for CPU1
SYSCON->CPUCTRL = (SYSCON->CPUCTRL | SYSCON_CPUCTRL_ENABLING_SEQ) & 
                  (~SYSCON_CPUCTRL_CPU1RSTEN_MASK);

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Failed to synch with multicore partner, . CPU1 CPU0.

The debugging session could not be started.
Either the debugger initialization filed, or else the file "iar_all_modules_loaded" was missing, corrupt or of an unsupported format.

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(Linker > Config) LPC55S69_cm33_core1_flash.icf LPC55S69_cm33_core1_ram.icf.
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main.c:

#include "string.h" // for memcpy.

SRAM, 1.

// Address of RAM, where the image for CPU1 should be copied
// According to UM11126 2.1.5 it is SRAM 3 on CM33 data bus
#define CORE1_BOOT_ADDRESS (void *)0x20033000

// Firmware image size calculation
uint32_t get_core1_image_size(void)
{
  uint32_t core1_image_size;
#pragma section = "__sec_core"
  core1_image_size = (uint32_t)__section_end("__sec_core") - 
                     (uint32_t)&core1_image_start;
  return core1_image_size;
}

1 FLASH- SRAM.

//  Copy CPU1 image to an other SRAM block
memcpy(CORE1_BOOT_ADDRESS, (void *)CORE1_IMAGE_START, get_core1_image_size());

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// Setup boot address
SYSCON->CPBOOT = SYSCON_CPBOOT_CPBOOT(CORE1_BOOT_ADDRESS);
```
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MAILBOX, . .

/**** Mailbox setup for mutex ****/
// Enable mailbox clocking
SYSCON->AHBCLKCTRLX[0] |=  SYSCON_AHBCLKCTRL0_MAILBOX_MASK;

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// Try to acquire mutex
while (!(MAILBOX->MUTEX & MAILBOX_MUTEX_EX_MASK));

// Release mutex
MAILBOX->MUTEX = MAILBOX_MUTEX_EX_MASK;

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0 ( )

#include "LPC55S69_cm33_core0.h"
#include "string.h"  // for memcpy

#define LED_GPIO_BLOCK 1
#define LED_GPIO_PIN 7

// Address of RAM, where the image for CPU1 should be copied
// According to UM11126 2.1.5 it is SRAM 3 on CM33 data bus
#define CORE1_BOOT_ADDRESS (void *) 0x20033000

// Sequence required to be written
// to SYSCON->CPUCTRL register ORed with other bits
// to applay settings
// See UM11126 4.5.70 for more details
#define SYSCON_CPUCTRL_ENABLING_SEQ 0xC0C40000

// Warning!!! IAR specific code. 
// core1_image_start is defined in 
// LPC55S69_cm33_core0_flash.icf linker config file
extern unsigned char core1_image_start[];
#define CORE1_IMAGE_START core1_image_start

static inline void Delay(void)
{
  for(int i = 0; i < 8000000; i++);
}

// Firmware image size calculation
uint32_t get_core1_image_size(void)
{
    uint32_t core1_image_size;
#pragma section = "__sec_core"
    core1_image_size = (uint32_t)__section_end("__sec_core") - 
                       (uint32_t)&core1_image_start;
    return core1_image_size;
}

int main()
{  
  /**** LED setup ****/
  // Enable clocking for GPIO1 (located on AHB bus)
  SYSCON->AHBCLKCTRLX[0] |= SYSCON_AHBCLKCTRL0_GPIO1_MASK;

  // Set direction for GPIO1 7 as output
  GPIO->DIR[LED_GPIO_BLOCK] |= GPIO_DIR_DIRP(1 << LED_GPIO_PIN);

  /**** Mailbox setup for mutex ****/
  // Enable mailbox clocking
  SYSCON->AHBCLKCTRLX[0] |=  SYSCON_AHBCLKCTRL0_MAILBOX_MASK;

  /**** CPU1 (slave) setup ****/
  //  Copy CPU1 image to an other SRAM block
  memcpy(CORE1_BOOT_ADDRESS, (void *)CORE1_IMAGE_START, get_core1_image_size());

  // Enable CPU1
  SYSCON->CPUCFG |= SYSCON_CPUCFG_CPU1ENABLE_MASK;

  // Setup firmware boot address
  SYSCON->CPBOOT = SYSCON_CPBOOT_CPBOOT(CORE1_BOOT_ADDRESS);

  // Enable clock and reset CPU1
  SYSCON->CPUCTRL = SYSCON->CPUCTRL | SYSCON_CPUCTRL_ENABLING_SEQ | 
                    SYSCON_CPUCTRL_CPU1RSTEN_MASK | SYSCON_CPUCTRL_CPU1CLKEN_MASK;

  // Release reset for CPU1
  SYSCON->CPUCTRL = (SYSCON->CPUCTRL | SYSCON_CPUCTRL_ENABLING_SEQ) & 
                    (~SYSCON_CPUCTRL_CPU1RSTEN_MASK);

  while(1)
  {
    /**** LED blinking ****/
    while (!(MAILBOX->MUTEX & MAILBOX_MUTEX_EX_MASK));  // Try to acquire mutex
    GPIO->B[LED_GPIO_BLOCK][LED_GPIO_PIN] = 0;          // Turn led On

    Delay();

    GPIO->B[LED_GPIO_BLOCK][LED_GPIO_PIN] = 1;  // Turn led off
    MAILBOX->MUTEX = MAILBOX_MUTEX_EX_MASK;     // Release mutex

    Delay();
  }
}

1 ( )

#include "LPC55S69_cm33_core1.h"

#define LED_GPIO_BLOCK 1
#define LED_GPIO_PIN 4

static inline void Delay(void)
{
  for(int i = 0; i < 8000000; i++);
}

int main()
{  
  /**** LED setup ****/
  // Enable clocking for GPIO1 (located on AHB bus)
  SYSCON->AHBCLKCTRLX[0] |= SYSCON_AHBCLKCTRL0_GPIO1_MASK;

  // Set direction for GPIO1 7 as output
  GPIO->DIR[LED_GPIO_BLOCK] |= GPIO_DIR_DIRP(1 << LED_GPIO_PIN);

  /**** Mailbox setup for mutex ****/
  // Enable mailbox clocking
  SYSCON->AHBCLKCTRLX[0] |=  SYSCON_AHBCLKCTRL0_MAILBOX_MASK;

  while(1)
  {
    /**** LED blinking ****/
    while (!(MAILBOX->MUTEX & MAILBOX_MUTEX_EX_MASK)); //  Try to acquire mutex
    GPIO->B[LED_GPIO_BLOCK][LED_GPIO_PIN] = 0;         // Turn led On

    Delay();

    GPIO->B[LED_GPIO_BLOCK][LED_GPIO_PIN] = 1;  // Turn led off
    MAILBOX->MUTEX = MAILBOX_MUTEX_EX_MASK;     // Release mutex

    Delay();
  }
}

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How to program multi-core microcontrollers

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