Arduino Uno Latency Timer?

Using Arduino Networking, Protocols, and Devices
1

Hello, I'm currently working on a project on measuring EMG and wanted to use the Arduino UNO, because the board I used before had only Bluetooth connection and I wanted a faster connection via USB. My problem is that between each two data bundles (with a few values) are 50 ms of latency, which is too much for what I want to achieve.
The other board had a FTDI chip and so it was possible to adjust the latency timer. Is there also the possibilty for the ACIA 6850 chip of the Arduino Uno somehow? Or is there any other solution to get rid off this latency?
Thank you in advance

2

Set the baudrate higher in Serial.begin().

3

Thank you, but I've already tried that. So it increases the number of data values in one data bundle, but still there are ~50ms between two data bundles. Or not just data bundles but any kind of output. So when I just e.g. just do:

void loop() {
Serial.println("1");
}

And I print this out with timestamps on my serial monitor, I get:
09:50:04.666 -> 1
09:50:04.666 -> 1
09:50:04.713 -> 1
09:50:04.713 -> 1
09:50:04.713 -> 1
09:50:04.713 -> 1
[...]

So between one bundle of prints and next one are ~50ms even with baudrates of 115200 and more

4

What you observe may be a Windows event management issue.

5

This is also possible. If so, do you have a suggestion how I could handle it or how I could check if it is?

6

With an Uno you can check the physical communication between the ATmega and the USB chip and between the USB chip and the PC. A logic analyzer may be helpful.

I wonder what bothers you with bundling. Does it slow down the Serial transmission?
Hmmm, cannot be because there is no synchronization between ATmega and USB chip, i.e. whatever is sent on Tx is sent over USB as well.

7

I want a small latency between data and my application. Also I need only the most current data. So it doesn't help to have data which is 10ms old or older.

8

Write your PC application program first and transfer real live data. Avoid the message driven GUI.

Eventually chose a real time system instead of Windows.

9

Alright I will try. I just thought, if it's something that is fixable easily it would be good to do this in the begining. So I wll try it out with a diffrent output system first.
Thanks for your help

10

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