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Author Topic: USB Serial Baud Rates? ... or other faster USB communication methods?  (Read 5854 times)
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Has anybody tested the what USB serial baud rates/speeds are achievable using a standard virtual COM port on a computer? How fast can this board go in practice??

I am hoping there will be improvements on the standard Arduino due to the faster processor...

Are there any other options for faster communication by using alternatives to a virtual COM port? What is the best data rate achievable (using any approach?)

Thanks
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This is not perfect test but increased the speed with Arduino Due programming port 57600-->115200 --> 230400 and errors started to appear
with 230400 bits/s,

but I do not know about Native port , though , since have not succeeded to install the driver yet, somebody else might know about this ?

with Arduino Mega I could use 230400 and even 460800 but with 460800 some errors started to appear but momentarily,

but like I said these are unofficial tests , since the result depends also on the code of the serial communication and
how often you do Serial.flush();
BR,
Seppo
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I have worked with an UNO at 500K - which is 1/32 of the clock - where 460800 is  1/34.7222 so not a nice divider of the clock. This causes errors.
- http://arduino.cc/forum/index.php/topic,61381.msg444421.html#msg444421 -


So I don't know the speed of the DUE but by taking a integer divider you should be able to get higher than the standard speed, with reasonable reliability.

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Hi guys,

Thanks for the responses.

I should have mentioned that I can get 500,000 on a standard Arduino Mega 1280 reliably... Has anyone else got experience with fast communication with the new more powerful due?

 
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Hello-
 I am using a Due connected to a processing program and I'm using 1843200 baud which is working nicely. I am pretty sure this limitation is in Processing. (Java). If I try to go faster I get a Java error.  But, it's working fine at this speed.

=Rich
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By the way that is on the USB port, not the programming port, using SerialUSB. I have the developer version of the Due and there is no programmer port.

This can probably go much faster and I'd like to but I have to use processing this time and that's the limit.

=Rich
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Hello-
 I am using a Due connected to a processing program and I'm using 1843200 baud which is working nicely. I am pretty sure this limitation is in Processing. (Java). If I try to go faster I get a Java error.  But, it's working fine at this speed.

=Rich
I somehow doubt this incredible number unless there is a typo with some extra '0' digit.
It seems there is no confirmed specification on this subject, so maximum stable speed is sort of 'gray area'.
I can get transmit rate of 250000 (Putty)
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Quote
1843200 baud
the due with its 84 MHz clock should be able to send at this rate, but for the receiving end it means ~184K interrupts per second that data is received. or 5 uSec to handle one. That might be the real bottleneck.
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I did some speed tests on the native port.  The short version: it's fast... smiley-wink

The long version is here:

http://arduino.cc/forum/index.php/topic,132811.msg999691.html#msg999691
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