[Ovmsdev] Password characters not received correctly

[Stephen Casner]

Has anyone else seen this phenomenon?  While connected to the USB
serial console and needing to issue the "enable" command and then
enter the module password, there have been a few instances where I
know I typed the password correctly and yet OVMS said no.  In fact,
sometimes it would say the password was wrong three times in a row
when I was typing very carefully each key in sequence.

I added some code to print out the characters that had been received
if the password was invalid.  I discovered that some, but not all, of
the characters were received as zero (NULL) instead of what I typed.
The last several times this has not occurred, though, so I don't have
a lot of datapoints.

I've looked at the code and don't see any obvious way this could
happen.  My best guess is some kind of timing problem between the UART
driver and my console_async code calling uart_read_bytes().

                                                        -- Steve