I have # avr-gcc --version avr-gcc (GCC) 4.3.2 Copyright (C) 2008 Free Software Foundation, Inc. ...
I want to use the ATmega128 and in/out instructions for registers below 0x40. # avr-gcc -mmcu=atmega128 -c -o 4x40-lcd.o xxx.c # avr-gcc -mmcu=atmega128 4x40-lcd.o -o xxx.elf -lc # avr-objdump -d xxx.elf ... 804: a2 e3 ldi r26, 0x32 ; 50 806: b0 e0 ldi r27, 0x00 ; 0 808: e2 e3 ldi r30, 0x32 ; 50 80a: f0 e0 ldi r31, 0x00 ; 0 80c: 80 81 ld r24, Z 80e: 8f 70 andi r24, 0x0F ; 15 810: 80 62 ori r24, 0x20 ; 32 812: 8c 93 st X, r24 ... This can be done with four instructions, in, andi, ori, and, out. And, 6 fewer clocks. How do I force avr-gcc to use in and out instructions on the ATmega128? tomdean _______________________________________________ AVR-GCC-list mailing list AVR-GCC-list@nongnu.org http://lists.nongnu.org/mailman/listinfo/avr-gcc-list
