USB2514 u***-serial接收奇怪的字符

您好，我使用的是定制的I.MX6板，它有一个USB接口连接。如果我连接USB到串行转换器（我使用多产PL2303）到UB2514上的一个下行USB端口，并且我将UART线的RX和TX短接在一起，所以我读回我写的东西，我注意到我可以正确地发送数据，但是当我接收到数据时，它被关闭了一个比特。我通过使用逻辑分析器来验证这一点，以确保当我键入“A”时，逻辑分析仪也读取“A”。但是当你看微型计算机的回声时，它会显示“@”。A“B”确实显示为“B”，所以LSB似乎被屏蔽了。为什么会发生这样的事情？我确信我已经消除了它是一个软件问题，我想知道这是否是一个硬件问题或固件发行的枢纽？



      以下为原文

    Hello,

I'm using a custom i.MX6 board, that has a USB2514 connected.  If I connect a USB to Serial converter (I'm using Prolific PL2303) to one of the downstreams USB ports on the USB2514, and I short the RX and TX of the uart wires together so I read back what I write, I've noticed that I can send data correctly, but when I receive data it is off by one bit.  I've verified this by using a logic analyzer to make sure that when I type "A", the logic analyzer also reads "A".  But when looking at the echo from minicom, it shows "@" instead.  A "B" does show up as "B", so it seems that the LSB is getting masked.  Any thoughts to why this is happening?  I'm pretty sure I've eliminated it being a software issue, and I'm wondering if it's a hardware issue or firmware issue of the hub?