ESP32-CAM Power Saving - XCLK undefined reference issue
Posted: Sat Oct 24, 2020 4:05 pm
Hi
I am using the ESP32-CAM board for a project running on batteries and need to save power. I have reduced the CPU frequency and other things, but now I am working on the Camera module. I only need to take a picture once every minute or two, so leaving it on and running all the time is wasting 30mA or so. Before initialising the camera, my device consumes around 50ma, after initialising (and after it settles after taking a picture) it consumes around 70ma.
There is some detailed advice here: https://github.com/espressif/esp32-camera/issues/33 about using the private xclk routines to save power, that apparently work, but I cannot get them to work.
Compiling the code below I get the errors:
The routines I am calling seem to exist in the binary file libesp32-camera.a which exists on my PC - but how do I use them?
My test code isolating this issue is below:
Thanks very much in advance.
Kevin
I am using the ESP32-CAM board for a project running on batteries and need to save power. I have reduced the CPU frequency and other things, but now I am working on the Camera module. I only need to take a picture once every minute or two, so leaving it on and running all the time is wasting 30mA or so. Before initialising the camera, my device consumes around 50ma, after initialising (and after it settles after taking a picture) it consumes around 70ma.
There is some detailed advice here: https://github.com/espressif/esp32-camera/issues/33 about using the private xclk routines to save power, that apparently work, but I cannot get them to work.
Compiling the code below I get the errors:
Code: Select all
C:\Users\W\AppData\Local\Temp\arduino_build_632483\sketch\Test.ino.cpp.o:(.literal._Z5setupv+0x30): undefined reference to `camera_enable_out_clock(camera_config_t*)'
C:\Users\W\AppData\Local\Temp\arduino_build_632483\sketch\Test.ino.cpp.o:(.literal._Z5setupv+0x34): undefined reference to `camera_disable_out_clock()'
C:\Users\W\AppData\Local\Temp\arduino_build_632483\sketch\Test.ino.cpp.o: In function `setup()':
C:\Users\W\Documents\ESP32 Cam Pico Project\Code\Test/Test.ino:77: undefined reference to `camera_enable_out_clock(camera_config_t*)'
C:\Users\W\Documents\ESP32 Cam Pico Project\Code\Test/Test.ino:81: undefined reference to `camera_disable_out_clock()'
collect2.exe: error: ld returned 1 exit status
exit status 1
Error compiling for board AI Thinker ESP32-CAM.My test code isolating this issue is below:
Code: Select all
#include <esp_camera.h>
// Forward declare cam clock stop/start.
esp_err_t camera_enable_out_clock(camera_config_t *config);
void camera_disable_out_clock();
// CAMERA_MODEL_AI_THINKER
#define PWDN_GPIO_NUM 32 //
#define RESET_GPIO_NUM -1
#define XCLK_GPIO_NUM 0 //
#define SIOD_GPIO_NUM 26
#define SIOC_GPIO_NUM 27
#define Y9_GPIO_NUM 35
#define Y8_GPIO_NUM 34
#define Y7_GPIO_NUM 39
#define Y6_GPIO_NUM 36
#define Y5_GPIO_NUM 21
#define Y4_GPIO_NUM 19
#define Y3_GPIO_NUM 18
#define Y2_GPIO_NUM 5
#define VSYNC_GPIO_NUM 25
#define HREF_GPIO_NUM 23
#define PCLK_GPIO_NUM 22 //
#define SerialDebug Serial // Nice names for Serial ports
camera_config_t cam_config;
camera_fb_t *fb; // Declare the variable for the pointer to the framebuffer
void setup() {
SerialDebug.begin(115200);
setCpuFrequencyMhz(20); // Save power by going slowly
// Init out Camera
cam_config.ledc_channel = LEDC_CHANNEL_0;
cam_config.ledc_timer = LEDC_TIMER_0;
cam_config.pin_d0 = Y2_GPIO_NUM;
cam_config.pin_d1 = Y3_GPIO_NUM;
cam_config.pin_d2 = Y4_GPIO_NUM;
cam_config.pin_d3 = Y5_GPIO_NUM;
cam_config.pin_d4 = Y6_GPIO_NUM;
cam_config.pin_d5 = Y7_GPIO_NUM;
cam_config.pin_d6 = Y8_GPIO_NUM;
cam_config.pin_d7 = Y9_GPIO_NUM;
cam_config.pin_xclk = XCLK_GPIO_NUM;
cam_config.pin_pclk = PCLK_GPIO_NUM;
cam_config.pin_vsync = VSYNC_GPIO_NUM;
cam_config.pin_href = HREF_GPIO_NUM;
cam_config.pin_sscb_sda = SIOD_GPIO_NUM;
cam_config.pin_sscb_scl = SIOC_GPIO_NUM;
cam_config.pin_pwdn = PWDN_GPIO_NUM;
cam_config.pin_reset = RESET_GPIO_NUM;
cam_config.xclk_freq_hz = 20000000;
cam_config.pixel_format = PIXFORMAT_JPEG;
//init with high specs to pre-allocate larger buffers
if (psramFound()) {
SerialDebug.println(" PS RAM Found.");
cam_config.frame_size = FRAMESIZE_UXGA;
cam_config.jpeg_quality = 10;
cam_config.fb_count = 2;
} else {
SerialDebug.println(" Error: PS RAM Not Found.");
cam_config.frame_size = FRAMESIZE_SVGA;
cam_config.jpeg_quality = 12;
cam_config.fb_count = 1;
}
// Overide the above for testing
cam_config.frame_size = FRAMESIZE_VGA;
cam_config.jpeg_quality = 10; // Quality of JPEG output. 0-63 lower means higher quality
cam_config.fb_count = 1;
delay(10000); // doing stuff here
esp_camera_init(&cam_config);
SerialDebug.printf(" Taking picture:\n");
setCpuFrequencyMhz(80); // Camera seems to need more than 40mhz to get a picture
camera_enable_out_clock(&cam_config);
delay(500);
fb = esp_camera_fb_get(); // Get the current frame buffer
delay(500);
camera_disable_out_clock();
setCpuFrequencyMhz(20);
SerialDebug.printf(" Picture length: %d\n", fb->len);
delay(10000); // doing stuff here
esp_camera_fb_return(fb);
}
void loop() {
}Kevin