To execute the program, .... you have some choice:
Simulator Run the program in the simulator with the following command:
  m6811-elf-run <prog>.elf
or
  m6811-elf-run -v <prog>.elf

The simulator recognizes the processor (68HC11 vs 68HC12) by looking at the ELF file.

Gdb Sim Gdb also includes a 68HC11 and 68HC12 simulator. To use it, type the following commands:

  m6811-elf-gdb <prog>.elf
  (gdb) target sim
  (gdb) load <prog>.elf
  (gdb) run

Gdb Monitor For CME11 boards:
  m6811-elf-gdb <prog>.elf
  (gdb) set remotebaud 9600
  (gdb) target buffalo /dev/ttyS2
  (gdb) load <prog>.elf
  (gdb) run

For CMD12 boards:

  m6811-elf-gdb <prog>.elf
  (gdb) set remotebaud 9600
  (gdb) target dbug /dev/ttyS2
  (gdb) load <prog>.elf
  (gdb) run

Bootstrap Upload the program (either <prog>.elf, or <prog>.s19) with your favorite target manager.
Prom Burn the <prog>.b file in some prom.