I'm receiving data over UART from another AVR. However I'm doing other stuff so don't want to have constantly keep polling the UART. I know there are interrupts but I can only see one for receive complete, which I assume still requires me to poll to complete the transfer.
Electronic – way to not have to poll the UART of an AVR
avrembedded
Related Solutions
Well, I wound up modifying the Stino plugin for sublime text to do what I wanted.
Stino is a plugin that lets you use a proper text-editor with the arduino processes.
Modified fork is available here. It's now part of the main Stino distribution.
I don't see where you put the correct F_CPU definition, which is mandatory for setbaud.h.
You also have to define the BAUD macro to use UBRR(L|H)_VALUE, like this:
#define F_CPU 1e6 // 1Mhz clock
#include <avr/io.h>
#include <util/delay.h>
void initUSART(void) {
#define BAUD 9600
#include <util/setbaud.h>
UBRR0H = UBRRH_VALUE;
UBRR0L = UBRRL_VALUE;
// ...
}
You can also calculate the UBRRnx values with this site. The values depend on your clock speed and the prescaler setting. At the default configuration it is simply one, so it is not used.
And don't forget the pull-up resistors (about 10K ohm) at the TX/RX lines.
I hope this helps.
Best Answer
There are interrupt vectors for both RXC and TXC (RX and TX complete) on AVRs. You should never have to poll for these unless you want to.
AVRFreaks has a nice post on this, and so does the manufacturer.