KL25Z ADC数据位疑问

只看该作者 · 2015-1-23 14:12

在ADC章节中ADCx_Rn寄存器中有这样的描述：sign-extended 2's complement这是什么意思啊？在11bit差分模式下ADC转换的结果怎样计算？

1万 · 2015-1-23 14:46

楼主你好！
这个问题用户手册讲的很清楚：
Unused bits in R n are cleared in unsigned right-justified modes and carry the sign bit
(MSB) in sign-extended 2's complement modes. For example, when configured for 10-bit
single-ended mode, D[15:10] are cleared. When configured for 11-bit differential mode,
D[15:10] carry the sign bit, that is, bit 10 extended through bit 15.
如果是11位差分，结果是2进制补码，D10是符号位。