Altera DE1-SoC - DE1-SoC 7-segment Displays

DE1-SOC COMPUTER SYSTEM WITH NIOS II For Quartus II 15.0
asm ( "SKIP_EA_DEC:" );
asm ( "stw r1, 4(sp)" ); // save all registers
asm ( "stw r2, 8(sp)" );
asm ( "stw r3, 12(sp)" );
asm ( "stw r4, 16(sp)" );
asm ( "stw r5, 20(sp)" );
asm ( "stw r6, 24(sp)" );
asm ( "stw r7, 28(sp)" );
asm ( "stw r8, 32(sp)" );
asm ( "stw r9, 36(sp)" );
asm ( "stw r10, 40(sp)" );
asm ( "stw r11, 44(sp)" );
asm ( "stw r12, 48(sp)" );
asm ( "stw r13, 52(sp)" );
asm ( "stw r14, 56(sp)" );
asm ( "stw r15, 60(sp)" );
asm ( "stw r16, 64(sp)" );
asm ( "stw r17, 68(sp)" );
asm ( "stw r18, 72(sp)" );
asm ( "stw r19, 76(sp)" );
asm ( "stw r20, 80(sp)" );
asm ( "stw r21, 84(sp)" );
asm ( "stw r22, 88(sp)" );
asm ( "stw r23, 92(sp)" );
asm ( "stw r25, 100(sp)" ); // r25 = bt (skip r24 = et, because it was saved above)
asm ( "stw r26, 104(sp)" ); // r26 = gp
// skip r27 because it is sp, and there is no point in saving this
asm ( "stw r28, 112(sp)" ); // r28 = fp
asm ( "stw r29, 116(sp)" ); // r29 = ea
asm ( "stw r30, 120(sp)" ); // r30 = ba
asm ( "stw r31, 124(sp)" ); // r31 = ra
asm ( "addi fp, sp, 128" );
asm ( "call interrupt_handler" ); // call the C language interrupt handler
asm ( "ldw r1, 4(sp)" ); // restore all registers
asm ( "ldw r2, 8(sp)" );
asm ( "ldw r3, 12(sp)" );
asm ( "ldw r4, 16(sp)" );
asm ( "ldw r5, 20(sp)" );
asm ( "ldw r6, 24(sp)" );
asm ( "ldw r7, 28(sp)" );
Figure 22. Reset and exception handler C language code (Part b).
Altera Corporation - University Program
2015
27