748339b281
RX and CTS are the input pins and pull-ups are enabled so they don't cause a problem if left unconnected. But the output pins don't need a pull up (they were originally all configured with pull up in commit 8f7491a109a555ca897ae49efe98f4cc2b080311). If needed, the pull-ups can be disabled in Python using machine.Pin after the UART is constructed. See issue #4369. Signed-off-by: Damien George <damien@micropython.org>