Added mult example

riscv/Makefile

@@ -8,8 +8,6 @@
 # Update the following variables to your environment
 # to run example program
 CROSS=/home/foo/IC/riscv-leon/rv32i/rv32i-gnu/bin/riscv32-unknown-elf-
-DESIGN_DIR=../designs/leon3-digilent-nexys4ddr
-
 #######################################################################
 CC=gcc
 AS=as
@@ -29,7 +27,7 @@ OBJCPFLAGS=-O binary -j .text
 # Note that target %.hex requeries %.S, not the makefile target %.s!
 # They are different here because there are modifications needed
 # on assembly code before running! (set stack, for example)
-# More details on example.s 
+# More details on README 
 #
 #################################################################
 # Target .o

riscv/main.S

@@ -23,6 +23,10 @@ _start:
 	sw	a0,-20(s0)
 	lw	a5,-24(s0)
 	add	a5,a5,1
+
+	# Move counter to x7
+	mv	x7,a5
+
 	sw	a5,-24(s0)
 	lw	a4,-20(s0)
 	li	a5,4096
@@ -34,7 +38,7 @@ _start:
 	add	sp,sp,32
 
 	###########################
-	# Move result to x6, since we dont have printf yet =( 
+	# Move i to x6, since we dont have printf yet =( 
 	mv	x6,a4
 	# Stop processor
 	sbreak

riscv/main.c

@@ -4,8 +4,7 @@ void _start(){
 	int i = 1;
 	int count = 0;
 
-	// Multiplies i by 4 while i < 4
-	// Read commentaries on main.s
+	// Multiplies i by 4
 	do{
 		i = mul(i,4);
 		count++;

riscv/to_text.c

@@ -1,50 +0,0 @@
-/*	Author: Lucas Castro
- *  Date:   10/09/2017
- *
- * Reads a binary file and converts its content to readable hexadecimal
- */
-
-#include <stdio.h>
-#include <stdint.h>
-
-int main(int argc, char** argv){
-	char word;
-	char res[8];
-	uint8_t i = 0;
-	FILE* input;
-	FILE* output;
-
-	if(argc != 3){
-		printf("Usage: ./<program name> <input bin file> <output readable hex file>\n");
-		return 1;
-	}
-
-	input = fopen(argv[1], "rb");
-	output = fopen(argv[2], "w");
-
-	if(input == NULL){
-		printf("Error opening input!\n");
-		return 1;
-	}
-	if(output == NULL){
-		fclose(input);
-		printf("Error opening output!\n");
-		return 1;
-	}
-
-	while(fread(&word, sizeof(unsigned char), 1, input)){
-		sprintf(res, "%02X", (unsigned char) word & 0xff);
-		fwrite(&res, sizeof(unsigned char), 2, output);
-
-		i++;
-		if(i == 4){
-			fwrite("\n", sizeof(char), 1, output);
-			i = 0;
-		}
-	}
-
-	fclose(input);
-	fclose(output);
-
-	return 0;
-}