此事涉及... 1. Software 是否正确的设定了 parity check? 2. Driver 是否正确的设定了 parity check? 3. Driver 如何处理 parity check error 的字符? 丢掉? 收下来? TL16C550C, TL16C550CI ASYNCHRONOUS COMMUNICATIONS ELEMENT WITH AUTOFLOW CONTROL SLLS177E – MARCH 1994 – REVISED APRIL1998 -- Texas Instruments line status register (LSR) Bit 2‡: This bit is the parity error (PE) indicator. When PE is set, it indicates that the parity of the received data character does not match the parity selected in the LCR (bit 4). PE is cleared every time the CPU reads the contents of the LSR. In the FIFO mode, this error is associated with the particular character in the FIFO to which it applies. This error is revealed to the CPU when its associated character is at the top of the FIFO. 不太容易判断是哪边出了问题. 不过, 实际上 parity check 的用途不大, 建议您将它设为 none 即可.