1. Since the baud rate in the ROM cannot be changed,
set the default baud rate of the 26Mhz version
of esp32c2 to 74800
2. Since the systimer configuration of the 26Mhz
version requires a non-integer systimer frequency
configuration, and this feature is not supported
in the current ROM, this option is disabled for
the 26Mhz version esp32c2