From Charles: "I'm afraid this is a limitation of PBP that probably won't be changed. The library routines (assembly language for high-level commands like HSEROUT) were written with the assumption that they would be in memory below 64K. They are the first thing placed after the RESET_ORG address. When I tested a variant of your code, the maximum address that could be safely defined was 0FFE4h. That limit will move down every time you use a new high level command which triggers a library inclusion.
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