ESP32 Forum

Code in ulp

.global x
x: .long 0

.global entry
entry:

move r0, x
ld r0, r0, x
add r0, r0, 1
halt


I comment before with another two tests, and anyone doenst worked

Should be e.g.:

.global x
x: .long 0

.global entry
entry:

move r1, x // load address of x in r1
ld r0, r1, 0 // load data from x in r0
add r0, r0, 1 // increment r0
st r0,r1,0 // store r0 as new content of x
halt

#include <C:\msys32\ESP32\ESP32\components\arduino\cores\esp32\Arduino.h>
#include <C:\msys32\ESP32\ESP32\components\arduino\libraries\WiFi\src\WiFi.h>
#include <C:\msys32\ESP32\esp-idf\components\freertos\include\freertos\FreeRTOS.h>
#include <C:\msys32\ESP32\esp-idf\components\freertos\include\freertos\task.h>
#include <C:\msys32\ESP32\esp-idf\components\esp32\include\esp_system.h>
#include <C:\msys32\ESP32\esp-idf\components\ulp\include\esp32\ulp.h>
#include <C:\msys32\ESP32\esp-idf\components\ulp\ulp.c>
#include <C:\msys32\ESP32\ESP32\build\main\ulp_main.h>



extern uint32_t ulp_x = 3;
extern const uint8_t ulp_main_bin_start[] asm("_binary_ulp_main_bin_start");
extern const uint8_t ulp_main_bin_end[]   asm("_binary_ulp_main_bin_end");
void ulp();


extern "C" void app_main()
{
	initArduino();
	Serial.begin(115200);
	

	ulp();
	


	Serial.printf("\nClock:%d  RAM: %d", ESP.getCpuFreqMHz(), ESP.getFreeHeap());
	esp_deep_sleep(15000000);
}

void ulp()
{
	Serial.printf("\nULP_X: %d", ulp_x & UINT16_MAX);
	delay(100);
	ulp_load_binary(0, ulp_main_bin_start, (ulp_main_bin_end - ulp_main_bin_start) / sizeof(uint32_t));
	ulp_run((&ulp_entry - RTC_SLOW_MEM) / sizeof(uint32_t));
	delay(100);
	Serial.printf("\nULP_X: %d", ulp_x & UINT16_MAX);
}

.global x
x: .long 0

.global entry
entry:

move r1, x // load address of x in r1
ld r0, r1, 0 // load data from x in r0
add r0, r0, 1 // increment r0
st r0,r1,0 // store r0 as new content of x
halt

Code in ulp

.global x
x: .long 0

.global entry
entry:

move r0, x
ld r0, r0, x
add r0, r0, 1
halt


I comment before with another two tests, and anyone doenst worked

Should be e.g.:

.global x
x: .long 0

.global entry
entry:

move r1, x // load address of x in r1
ld r0, r1, 0 // load data from x in r0
add r0, r0, 1 // increment r0
st r0,r1,0 // store r0 as new content of x
halt

Well, doenst work too. Variable still in value declared in C

Images: https://i.imgur.com/0sWX7Z6.png https://i.imgur.com/Tr9yMz7.png

Code in C:

Code: Select all

#include <C:\msys32\ESP32\ESP32\components\arduino\cores\esp32\Arduino.h>
#include <C:\msys32\ESP32\ESP32\components\arduino\libraries\WiFi\src\WiFi.h>
#include <C:\msys32\ESP32\esp-idf\components\freertos\include\freertos\FreeRTOS.h>
#include <C:\msys32\ESP32\esp-idf\components\freertos\include\freertos\task.h>
#include <C:\msys32\ESP32\esp-idf\components\esp32\include\esp_system.h>
#include <C:\msys32\ESP32\esp-idf\components\ulp\include\esp32\ulp.h>
#include <C:\msys32\ESP32\esp-idf\components\ulp\ulp.c>
#include <C:\msys32\ESP32\ESP32\build\main\ulp_main.h>



extern uint32_t ulp_x = 1;
extern const uint8_t ulp_main_bin_start[] asm("_binary_ulp_main_bin_start");
extern const uint8_t ulp_main_bin_end[]   asm("_binary_ulp_main_bin_end");
void ulp();


extern "C" void app_main()
{
	initArduino();
	Serial.begin(115200);
	

	ulp();
	


	Serial.printf("\nClock:%d  RAM: %d", ESP.getCpuFreqMHz(), ESP.getFreeHeap());
	esp_deep_sleep(15000000);
}

void ulp()
{
	Serial.printf("\nULP_X: %d", ulp_x & UINT16_MAX);
	delay(100);
	ulp_load_binary(0, ulp_main_bin_start, (ulp_main_bin_end - ulp_main_bin_start) / sizeof(uint32_t));
	ulp_run((&ulp_entry - RTC_SLOW_MEM) / sizeof(uint32_t));
	delay(100);
	Serial.printf("\nULP_X: %d", ulp_x & UINT16_MAX);
}

Code in assembly:

Code: Select all

.global x
x: .long 0

.global entry
entry:

move r1, x // load address of x in r1
ld r0, r1, 0 // load data from x in r0
add r0, r0, 1 // increment r0
st r0,r1,0 // store r0 as new content of x
halt

I see the ulp binary code (including the "x" variable definition) being loaded from scratch to the ESP32's RTC_SLOW_MEM memory on each wakeup .
Instead I would use technique shown here to load it only once on hard reset.

Otherwise this variable will be reset on each wakeup.

Ah, sorry. Now I see you are printing the value before and after loading the ulp code.
I will look into it sometime later today.

Are you sure the compiler (on the main application side) is not optimizing the second load of ulp_x away? If it does, then casting ulp_x to a volatile variable might help.

// Variable definitions for ESP32ULP
// This file is generated automatically by esp32ulp_mapgen.py utility

#pragma once

extern uint32_t ulp_x;
extern volatile uint32_t ulp_entry;

Maybe you should remove global initialization of ulp_x and only set value if it is a cold boot.

.global x
	x: .long 0


.global entry
entry:

	move r1, x
	ld r0, r1, 0
	add r0, r0, 5
	st r0,r1,0
	halt