The following two subroutines will switch back and forth. The software was written assuming the variable "ADRS" is assigned as it is in the subroutine starting at line 2000 of MAXWELL on the Tool Kit diskette.
3000  REM       TURN OFF HRCG
3010  PRINT CHR$(4);"PR#0"
3020  PRINT CHR$(4);"IN#0"
3030  HOME
3040  TEXT
3050  RETURN
4000  REM       TURN ON HRCG
4010  CALL ADRS + 3
4020  RETURN
Beware: HRCG overwrites the text screen when outputting to the High-Res screen. It will destroy any information there. You will have to rewrite the text screen after using HRCG.