tool.c

来自「JTAG编程的全套资料」· C语言 代码 · 共 53 行

/*
 * tool.c:	this file implements some routes as	public tools
 *
 * Copyright (C) 2004, OPEN-JTAG, All rights reserved.
 */

#include "types.h"


/*
 * tool_reverse_bit_order() -
 *		Reverse the bit order of the input.
 *		The input is regarded as a bit sequence. This sequence is 
 *		totally reversed.
 */
void tool_reverse_bit_order(int bit_len, const u32 *input, u32 *output)
{
	int bit_idx, bit_val;
	int b_len, w_len;
	u32 in_data, out_data;
	
	if(bit_len <= 0)
		return;

	b_len = bit_len%32;
	w_len = bit_len/32;
	in_data = 0;
	out_data = 0;

	for(bit_idx = 0; bit_idx < bit_len; bit_idx++){
		if( (bit_idx % 32) == 0)
			in_data = input[bit_idx/32];
		
		bit_val = in_data & 0x1;
		in_data >>= 1;
	
		if(b_len == 0){
			out_data = 0;
			b_len = 32;
			w_len --;
		}

		b_len --;
		out_data |= (bit_val << b_len);

		if(b_len == 0)
			output[w_len] = out_data;
	}
	
	return;
}