Does someone knows the maximal speed for bluetooth on the arduino uno R4. Currently I am able to send around 17 bytes in 5 ms (using notify on other site) using writevalue.
Polling for new data takes also 5 ms (readvalue), but maybe this could be done faster using notify.
I know maybe the serial bridge between both processors may be a limiting factor, but I am able to receive data using the serial command at 230400 baud, so the speed of the bridge must be at least 230400 bps, I guess (or does this differ in arduinoBLE)
Reading the documentation, 2 Mbps should be possible (And of course I know it also depends on the other site, this is a macbook and I assume this is fast enought) Or shoudl I sned larger packages to avoid large start and stop timings?
Does anyone know where can I found technical documentation about this?
Tech docs are on the Arduino.cc site, under Hardware then UNO R4.
While using a larger payload does increase throughput, an error causes a bigger recovery time so it's a balancing act. Increase payload size until throughput starts to drop due to resends.
I'm currently working with the UNO R4 WIFI and the ArduinoBLE library. The maximum data rate I've achieved is 6426 bytes / s using notify, sending 27 notifications of 238 bytes per second. I'm currently using the UNO R4 as peripheral and I've tried with my phone as a central device (using nRF Connect app) and my pc with a Python script using Bleak.
As the docs say a characteristic value can be up to 512 bytes long, but this seems to change when a central device subscribes to the UNO, as the MTU is reduced to 242 bytes with no possibility of changing it by a request from the central. Removing the 3-byte header leaves me with a maximum size of 239 per message, but I'm using 238 because I'm sending short uint16_t values.
I don't know if this is the normal behavior, but I would really like to have those 512 bytes per notification for the project I'm working on.
I know it's been almost a year since this discussion began, but I hope it will be helpful to someone.
