I wrote a script that generates the C code for new delay
tables that can be inserted into NewSoftSerial.
The script uses the 8MHz and 16MHz values from
the existing code to generate new values.
I had the script generate values for 20MHz and compared
the new values with the existing values. At the low baud rates
the values are in agreement. The numbers seem a little off
at the high baud rates so they may need to be tweeked.
No hexadecimal dollars for bugs in the script but I will
do my best to fix them quickly

The script and the table I generated for F_CPU = 12MHz
are at
http://wiblocks.luciani.org/docs/app-notes/software-serial.html(* jcl *)
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