bits和real之间的转换系统函数

江锋渔火

已于 2022-03-06 00:00:08 修改

阅读量2.6k

点赞数

分类专栏： verilog系统函数文章标签： fpga开发

于 2022-03-05 23:28:39 首次发布

本文链接：https://blog.youkuaiyun.com/weixin_40877998/article/details/123303270

版权

verilog系统函数专栏收录该内容

1 篇文章

订阅专栏

bits, real, shortreal之间的转换

系统函数	说明
$bitstoreal	64bit的整数转换为双精度浮点数
$bitstoshortreal	把64bit的整数转换为单精度浮点数
$realtobits	双精度浮点数据转换为63bit整数
$shortrealtobits	单精度浮点数据转换为63bit整数

例如：

	localparam [31:0] test = 32'h3fb0d05d;
	localparam [63:0] test2 = 64'h3fb0d05d;
	localparam [63:0] test3 = 64'hc00e35603fb0d05d;
	localparam [63:0] test_long = 64'h_3FF61A0BE5109071;
	real rr = 3.14;

	initial begin
		$display("$bitstoreal(test) = %h = %f", test, $bitstoreal(test));
    	$display("$bitstoreal(test3) = %h = %f", test3, $bitstoreal(test3));
		$display("$bitstoreal(test_long) = %h = %f", test_long, $bitstoreal(test_long));
    	
		$display("$bitstoshortreal(test) = %h = %f", test, $bitstoshortreal(test));
    	$display("$bitstoshortreal(test2) = %h = %f", test2, $bitstoshortreal(test2));

		$display("$realtobits(rr)		= %f = %h ", rr, $realtobits(rr)	);
		$display("$shortrealtobits(rr)  = %f = %h ", rr, $shortrealtobits(rr)	);
	end

打印结果：

# $bitstoreal(test) = 3fb0d05d = 0.000000
# $bitstoreal(test3) = c00e35603fb0d05d = -3.776062
# $bitstoreal(test_long) = 3ff61a0be5109071 = 1.381359
# $bitstoshortreal(test) = 3fb0d05d = 1.381359
# $bitstoshortreal(test2) = 000000003fb0d05d = 1.381359
# $realtobits(rr)		= 3.140000 = 40091eb851eb851f 
# $shortrealtobits(rr)  = 3.140000 = 4048f5c3