I compiled a simple spi C program, as per: http://linux-sunxi.org/SPIdev#In_the_user_space PID PPID USER STAT VSZ %VSZ %CPU COMMAND 3768 1816 root R 900 1% 65% ./spi The %VSZ value remains constant. while (1==1){ buffer=(char *)spi_read(0x10,0x0A,11,file); //reading the address 0x100A for (i =0; i < 11; i++) { printf("%X ",buffer[i]); } } I am planning to make a daemon C program that stores reads from the SPI device in a /tmp/buffer file. Then I can read the file with Python.