How to shutdown console redirection

[hz hanks]

Hi, all~
I'm studying in an embedded Linux board with only one uart, which is
set default as the console display. Now as I try to develop uart
driver, I want to shutdown this console redirection temporarily. But I
don't know how? I search the Internet, but there's only the tutorial
for setting this redirection rather than shutdown it. Is there anyone
can help? Thank you very much.