Hello!
Let's start talking about what I'm trying to do. The Bluetooth protocol have a feature called AFH (adaptative frequency hopping) that monitors the quality of each Bluetooth channel and include or exclude them of a channel map for the frequency hopping. I'm trying to reproduce this with a link made with 2 ESP-32, using the host layer of NimBle stack.
Then I connected these two devices, one as "blecent" and one as "bleprph". I also implemented a function of NimBle HCI (the function was ble_hs_hci_read_chan_map(conn_handle, channel_map) from ble_hs_hci.h) to read the channel map.
When I connect blecent to bleprph and I try to read the channel map, I can see only all channels (0-36 excluding 37/38 and 39 that are advertisement channels) as one that means no interference. No matter how much interferece I'm generating with a USRP in this band, no channel changes (from 0 to 36) changes to zero.
If I connect the bleprph to a smartphone, I can se a lot of "zeros" where there are wifi channels beeing used, meaning that AFH is doing its role.
I supposed that when I connect two ESP-32, the controler layer may use PER to decide about channel quality and as there's no data traffic between then, it may be the reason that I can't disable any channel with the interference I'm generating.
So, I started trying to connect blecent to blehr (that simulates a heart rate sensor) to se if it works. BUT, I connect them but I don't know how to make the blecent ask for notifications for the blehr. When I connect it to a smartphone, I ask for notifications and keep seeing it simulating a sensor, with blecent I only receive that "peer doesn't ANS New Alert Notification ....".
Finally my question, what is missing to blecent work as a Gatt client and be able to read the heart rate measurements simulated by blehr example? I changed blehr, then both are already connected.
Or the reading of channel map from AFH will not be possible this way connecting two ESP-32 with NimBle stack?
Thanks and sorry for this giant question!
GATT Client on blecent + AFH
-
- Posts: 5
- Joined: Fri Aug 23, 2019 8:02 pm
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: audris, Google [Bot] and 87 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.