Hi,
I am new here and experimenting with my first uC (Seeeduino Mega).
I am working with Serial Ports (via NewSoftSerial)...
Can someone of you tell me, if a higher baudrate generates a higher load on the Atmega slowing down other processes?
(so the conclusion would be to use the slowest possible baudrate to transfer the data needed...)
Thank you in advance
Kai
NewSoftSerial is informed by the presence of data to read by an interrupt. When the interrupt occurs, the interrupt handler is invoked, and reads an entire character.
Faster baud rates mean that the time required to read a character is reduced.
This means also that the time between characters is reduced, and, therefore, that the interrupt handler could be called more often.
The "load on the CPU" doesn't change based on baud rate. It takes no more effort to read data slowly than it does to read it quickly.
The amount of data, on the other hand, does matter. More data takes longer.
Typically, if low baud rates are used, there is a greater emphasis on minimizing data.
If a higher baudrate generates a higher load on the Atmega slowing down other processes?
The ATmega only runs one process at a time. The amount of data and speed you transfer will determine the amount of time is available to complete your other tasks.
So it doesnt depend on the baud rate but on the data coming in? So when I get the same data stream per second there is no difference for the ATmega if its at 9600 or 38400 baud rate?
Kai
So when I get the same data stream per second there is no difference for the ATmega if its at 9600 or 38400 baud rate?
No. The number of bytes per second is defined by the baud rate. The impact on the Arduino is the same (number of bytes total) regardless of how long it takes.