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Altera_Forum
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20 years ago

How to tell there is data from UART?

Hi Browsing through Altera documentation suggests I should be using the HAL with a UART. So using the HAL how do I determine if there is data available from the UART before calling getchar...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
20 years ago

open device uart in non blocking mode:

static int fdterm; // FILEDESCRIPTOR RETURNED BY OPEN

..

fdterm = open("/dev/uart1", O_RDWR | O_NONBLOCK | O_NOCTTY);

..

reading is done by

..

res=read(fdterm,uart1_tempbuff,sizeof(uart1_tempbuff)-1);

if(res>0) {

... we have received some bytes

}