Hi all,
I have encountered a problem when I use the i2s_ADC mode with high sampling rate (about 60kHz). The board I used is ESP32-DevKitC V4. The problem is that some values may cannot be read by ADC in this mode. There are obvious blank gaps of the measurement signal which should be varied uniformly in certain range. After simple analysis, it seems that the values in the blank gaps are all read as a same value that is the edge of the gap. And I also found that the edge of the blank gap are usually occured to be X1F, X3F, X7F and XFF (hexadecimal value).
There are several pictures that may help to make my problems clear. Fig 1 was my testing circuit of and I measured the voltage of Rs. Fig 2 was the signal read by i2s_ADC and Fig 3 was the same signal read by osiliscope. It is distribution histogram. The x axis represent the measured value and y axis represent the times these values appear. It is obvious that there is huge blank gap in the siganl read by i2s_ADC. The original value read by i2s_ADC can be seen that the values between 1279(4FF) and 1327(52F) are lost. I also summarized more values measured in other ranges and the blank gap also existed. The start point of blank gap are always X1F, X3F, X7F and XFF. It is very interesting but I donnot know why. It will be very appreciated if someone know what happened. Thanks a lot!
Lack of values using I2S_ADC
Return to “General Discussion”
Jump to
- English Forum
- Explore
- News
- General Discussion
- FAQ
- Documentation
- Documentation
- Sample Code
- Discussion Forum
- Hardware
- ESP-IDF
- ESP-BOX
- ESP-ADF
- ESP-MDF
- ESP-WHO
- ESP-SkaiNet
- ESP32 Arduino
- IDEs for ESP-IDF
- ESP-AT
- ESP IoT Solution
- ESP RainMaker
- Rust
- ESP8266
- Report Bugs
- Showcase
- Chinese Forum 中文社区
- 活动区
- 乐鑫活动专区
- 讨论区
- 全国大学生物联网设计竞赛乐鑫答疑专区
- ESP-IDF 中文讨论版
- 《ESP32-C3 物联网工程开发实战》书籍讨论版
- 中文文档讨论版
- ESP-AT 中文讨论版
- ESP-BOX 中文讨论版
- ESP IoT Solution 中文讨论版
- ESP-ADF 中文讨论版
- ESP Mesh 中文讨论版
- ESP Cloud 中文讨论版
- ESP-WHO 中文讨论版
- ESP-SkaiNet 中文讨论版
- ESP 生产支持讨论版
- 硬件问题讨论
- 项目展示
Who is online
Users browsing this forum: No registered users and 47 guests
- All times are UTC
- Top
- Delete cookies
About Us
Espressif Systems is a fabless semiconductor company providing cutting-edge low power WiFi SoCs and wireless solutions for wireless communications and Internet of Things applications. ESP8266EX and ESP32 are some of our products.