Imagecraft c compiler and development environment for the atmel avr

ICCV8 for AVR – C Compiler for Atmel AVRStandard IO FunctionsSince standard file IO is not meaningful for an embedded microcontroller, much of thestandard stdio.h content is not applicable. Nevertheless, some IO functions aresupported. Use #include before using these functions. You will need toinitialize the output port. The lowest level of IO routines consists of the singlecharacterinput (getchar) and output (putchar) routines. You will need toimplement these routines since they are specific to the target device. We provideexample implementations and for most cases, you just need to copy the correctexample file to your project. See the function descriptions below. You do not need tomake modifications to the high-level standard IO functions such as printf,sprintf, scanf, etc.Using printf on Multiple Output DevicesIt is very simple to use printf on multiple devices. You can write your ownputchar() that writes to different devices depending on a global variable and afunction that changes this variable. Then it is just a matter of calling the device changefunction when you want to switch to use a different device. You can even implement aversion of printf that takes some sort of device number argument by using thevfprintf() function, described below.List of Standard IO Functions int getchar(void)returns a character. You must implement this function as it is device-specific.There are example functions that use the UART registers in the directoryc:\iccv8avr\examples.avr\ with file names getchar???.c. You maymake a copy of the file that matches your target and make any modifications ifneeded and add it to your project file list. int printf(char *fmt, ..)printf prints out formatted text according to the format specifiers in the fmtstring. NOTE: printf is supplied in three versions, depending on your codesize and feature requirements (the more features, the higher the code size): Basic: only %c, %d, %x, %u, %p, and %s format specifiers without modifiersare accepted. Long: the long modifiers %ld, %lu, %lx are supported, in addition to thewidth and precision fields. Floating-point: all formats, including %f for floating-point, are supported.95