Can I use DMA for ESP32C3`IIC to drive ssd1306?

[XH_Timmo]

It has afterimage when I using ESP32C3`IIC to drive ssd1306 with 1 MHz. So I want to solve this problen with DMA. But in Technical Manuals, I can`t find IIC config in DMA, like this:

屏幕截图 2024-08-17 170549.png (33.94 KiB) Viewed 1225 times

This is my code to write data:

Code: [Select all] [Expand/Collapse]

1. static esp_err_t ssd1306_write_data(void *sensor, const uint8_t *const data_buf,
2.                                     const uint8_t data_len) {
3.   ssd1306_dev_t *sens = (ssd1306_dev_t *)sensor;
4.   esp_err_t ret;
5.  
6.   i2c_cmd_handle_t cmd = i2c_cmd_link_create();
7.   ret = i2c_master_start(cmd);
8.   assert(ESP_OK == ret);
9.   ret = i2c_master_write_byte(cmd, sens->dev_addr | I2C_MASTER_WRITE, true);
10.   assert(ESP_OK == ret);
11.   ret = i2c_master_write_byte(cmd, 0x40, true);
12.   assert(ESP_OK == ret);
13.   ret = i2c_master_write(cmd, data_buf, data_len, true);
14.   assert(ESP_OK == ret);
15.   ret = i2c_master_stop(cmd);
16.   assert(ESP_OK == ret);
17.   ret = i2c_master_cmd_begin(sens->bus, cmd, 1000 / portTICK_PERIOD_MS);
18.   i2c_cmd_link_delete(cmd);
19.  
20.   return ret;
21. }

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This is my code to init ssd1306:

Code: [Select all] [Expand/Collapse]

1. void SSD1306_init(void) {
2.  
3.   esp_err_t ret;
4.  
5.   ssd1306 = ssd1306_create(I2C_MASTER_NUM, SSD1306_ADDR);
6.   TEST_ASSERT_NOT_NULL_MESSAGE(ssd1306, "SSD1306 create returned NULL");
7.   ssd1306_write_cmd(ssd1306, 0xAE);
8.   ssd1306_write_cmd(ssd1306, 0x00);
9.   ssd1306_write_cmd(ssd1306, 0x10);
10.   ssd1306_write_cmd(ssd1306, 0x40);
11.   ssd1306_write_cmd(ssd1306, 0xB0);
12.   ssd1306_write_cmd(ssd1306, 0x81);
13.   ssd1306_write_cmd(ssd1306, 0xFF);
14.   ssd1306_write_cmd(ssd1306, 0xA1);
15.   ssd1306_write_cmd(ssd1306, 0xA6);
16.   ssd1306_write_cmd(ssd1306, 0xA8);
17.   ssd1306_write_cmd(ssd1306, 0x3F);
18.   ssd1306_write_cmd(ssd1306, 0xC8);
19.   ssd1306_write_cmd(ssd1306, 0xD3);
20.   ssd1306_write_cmd(ssd1306, 0x00);
21.   ssd1306_write_cmd(ssd1306, 0xD5);
22.   ssd1306_write_cmd(ssd1306, 0x80);
23.   ssd1306_write_cmd(ssd1306, 0xD8);
24.   ssd1306_write_cmd(ssd1306, 0x05);
25.   ssd1306_write_cmd(ssd1306, 0xD9);
26.   ssd1306_write_cmd(ssd1306, 0xF1);
27.   ssd1306_write_cmd(ssd1306, 0xDA);
28.   ssd1306_write_cmd(ssd1306, 0x12);
29.   ssd1306_write_cmd(ssd1306, 0xDB);
30.   ssd1306_write_cmd(ssd1306, 0x30);
31.   ssd1306_write_cmd(ssd1306, 0x8D);
32.   ssd1306_write_cmd(ssd1306, 0x14);
33.   ssd1306_write_cmd(ssd1306, 0xAF);
34.  
35.   ssd1306_clean();
36.   ESP_LOGI(TAG, "Finish init %s", TAG);
37. }

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[ESP_Sprite]

No, I2C doesn't support DMA. Note that this generally also is not needed as the I2C protocol itself is not really that fast. If your display supports it, you can try using SPI; that can go faster and does support DMA.

[XH_Timmo]

Thank you. I will look for a better displayer.

[MicroController]

It has afterimage

What does that mean?

So I want to solve this problem with DMA.

How would using DMA solve your problem?

[XH_Timmo]

What does that mean?

Sorry, my English is bad , I meanings “残影” , looks like flash frequence is not enough.

How would using DMA solve your problem?

If I can use DMA, my transmission will be faster than now.

[QQ26750452]

这是一个悲催的现实！国语分论坛一年半载没人回复，只能用蹩脚的英语硬着头皮混在英文分区里提问！

[MicroController]

If I can use DMA, my transmission will be faster than now.

No, it would not.
I'm not sure what the problem is you're seeing, but it may be more of a timing issue, i.e. synchronization with the display's refresh cycle.
How many pixels at what framerate do you want to draw?