BLOCK_BUFFER_SIZE was not declared in this scope (no replies)

i am trying to reload Marlin on a newly repaired Mini Rambo controller. Using Marline 1.1 code and Arduino IDE 1.8.9

When I try to compile the firmware, I get an error in Marlin_main.cpp:: "BLOCK_BUFFER_SIZE was not declared in this scope". Can somebody help me to figure out what I need to do to get past this?

I used this board for a couple years with an older version of Marlin firmware that I can no longer find.

Thanks