Prepare Arduino Serial for 1802 bin files

Want to sent bin files to Mega where they will be put into vRAM[] to be used when running 1802 in slow mode, just as if they were in ROM, the bytes.
Practiced using Uno with little program that waits for BrayTerm++ to send a bin file that was the output of an a18.exe assembly process.

Looks a bit like this below.

Bray Terminal Program keeps being best of its kind and may be used in this project instead of Arduino's terminal.