I'm trying to communicate with BLE between Android App and Apollo devices.But When App is running normally, |App and Apollo device don't communicate well
What I want to know is Apollo device'BLE device communication type and communication's max length.
I'm new to BLE.
I already downloaded BLE-master(Android App source code) and used Apollo SDK(osaap-uart-server.uvprojx).
And also used Keil 5.20 for device programming.
when Android App and Apollo device is connecting, communication length is limit to 20cm.
I don't know the reason why the distance is so small.
How do I do to increase communiation distance?
Apollo advertising code are follows .
Related
I have a BLE temperature sensor, which should send measurements to an ESP32 via a BLE connection and my plan was that the ESP32 could send the measurements via WiFi to my database (Firebase Realtime Database). However, I have seen from a few tutorials that a mqtt server would be neccesary (see the screenshot below - link to the video: https://www.youtube.com/watch?v=PBYCG-ypvRY). Could someone please explain to me why the mqtt component is neccesary? Currently I am measuring temperatures using my ESP32 (without the BLE temperautre sensors) and sending them directly to the database, so I am confused as to why with BLE I would need a mqtt server.
Thanks for your help in advance!
You don't need MQTT. It's just one of the IoT-friendly protocol alternatives (like HTTPS, AMQP, CoAP, homebrew, etc) available to you for device-to-server communication. There are pros and cons to each one. It's up to you to choose whatever solution is relevant to your system.
If you've already implemented the Firebase HTTPS interface and it does the job, you're done.
If you are having problems, note that the Google IoT Core also prescribes MQTT (or, alternatively HTTPS) as an underlying messaging protocol - used together with the Device SDK for Embedded C. But this is for people who want to have a large-scale authentication and management solution for their devices. By all means, stick to your existing solution if it works.
I am working on CC2541 BLE controller. I am using SimpleBLEPeripheral from TI BLE stack which is available on TI's website. I have interfaced the controller with a sensor whose state changes at an interval of 3 seconds. This means that event is generated at every 3 seconds. I am using custom profile's UUID whose length is 128 bits. I have also developed an app to get the sensor's data on my app. All is working good but device is getting disconnected with the app after establishing a connection.
I also tried changing the Connection Parameter in firmware but the issue is not resolved yet.
What should I try to make this connection flawless? I want that device should not get disconnected when it is in range and also if the device is out of range for sometime, it should auto reconnect with the app when it comes in the range of the mobile phone.
I have created a BLE peripheral that exposes a GATT service. It uses BlueZ 5.50, but it seems that only one device can connect to the GATT service. When the device is connected, then other devices can't see it anymore. It's not showing up in a scan anymore and if it was already scanned, then I can't connect to it anymore.
It seems to be a limitation or configuration issue in BlueZ, because when using the Paypal GATT library it can handle multiple connections. As far as I know, the RPi3 BLE chip should be able to handle up to 10 connections.
Does anyone know if this can be done using BlueZ?
The Paypal GATT library directly connects to the HCI device and bypasses most of the kernel stuff. BlueZ depends on kernel drivers and user-space applications and is capable if the driver reports that the controller allows multiple connections. You need a decent BLE controller and a recent kernel to make it work.
More information can be found in https://github.com/bluez/bluez/issues/12.
I'm using Android Things 1.0.4 in a prototype where it acts as BLE peripheral device: advertising services and running a GATT server.
I encounter an issue in the BLE pairing process when trying to bond the Android Things board (Raspberry Pi 3) and a smartphone.
Since the device has no display, I set using BluetoothConfigManager:
IoCapability = BluetoothConfigManager.IO_CAPABILITY_NONE
which results in the error AUTH_FAILED every time.
Instead,
IoCapability = BluetoothConfigManager.IO_CAPABILITY_OUT
logs the pairing key and prompts the smartphone to enter it during pairing, but it results in the REMOVED error.
Questions:
Is Android Things in peripheral role capable of handling BLE pairing or not yet?
Are there more things that need to be implemented in the app's code to replicate the full-fledged Android logic?
Here's the source code of the Android Things app to test BLE pairing and bonding
The same code stripped from Android Things specific elements completes BLE pairing and bonding successfully when running on an Android phone as Peripheral (server), and an Android device or iPhone as Central (client).
Generally speaking, if you attempt to read an encrypted GATT characteristic before pairing (which triggers the pairing logic automatically), this results in GATT error 137 returned from the read request (AUTH_FAIL). This is because the device doesn't have enough time to finish setting up the bond before a response is sent by the Bluetooth stack. Retying the read request again generally succeeds.
I have not tested this with an iOS client device, but it certainly holds true with an Android client connecting to an Android (Things) peripheral. As such, I would recommend a few things:
Have the client (mobile) device explicitly initiate pairing, and Android Things should simply react to these incoming requests in the BluetoothPairingCallback. This lets the mobile device decide the pairing type based on the reported capabilities of the IoT device.
Separate the pairing flow from the GATT flow. Pair to the discovered device separately from making any attempts to read the characteristics. This tends to be the best way to avoid timing problems.
Regarding capability choices, this depends on your device. In my experience, if you choose IO_CAPABILITY_NONE this results in PAIRING_VARIANT_CONSENT inside of onPairingInitiated() and the pairing operation succeeds once finishPairing() is called. If you adjust your capabilities, you should be prepared for any number of the variants requiring you to display a PIN for the mobile device to enter. I have not not personally tested these paths.
I have a CSR4.0 BLE dongle I am using in Raspberry Pi. I am using Bluez stack in the Pi and can make the dongle up & running. Now, when I use some iOS app (LightBlue) to find out nearby BLE devices, most of the time it can't find the CSR device.
A few times the app can find the CSR device, but when I press CSR name in the app, the app tries to connect to the CSR dongle but fails. Then the dongle becomes invisible.
Any thought on why this happens? How can I reliably find the CSR dongle? And how can I connect to it? Do I need to write some BLE application code to run on the Raspberry Pi?
You'll need to advertise a BLE service on the Pi so LightBlue can discover it from your iPhone.
One way to do this is to create a service on the Raspberry Pi using Bleno. Try the battery-service example.