现在发现一个问题,根据datasheet:
Figure 49-304. ISO-7816 T = 0 data format
As with other protocols supported by the UART, the data character includes a start bit.
However, in this case, there are two stop bits rather than the typical single stop bit.
意思就是T=0下数据都是有2个停止位,而我用示波器发现IC卡只有1点几个停止位,数据是对的,只是停止位不对,导致每次只能正确读到返回数据的第一个字节。