Texas Instruments TI-80 User Manual - Page 160

LBL GOTO LBL (label) and GOTO (go to) are used together for branching. LBL (PRGM CTL, item 7) gives a label to a command line in a program. The label is one character (A-Z, 0-9, or q). LBL label GOTO (PRGM CTL, item 8) causes the program to branch to the command line with the same label. GOTO label PRGM_ RETURN STOP PRGM_ (PRGM CTL, item 9) calls (executes) other programs as subroutines (pages 10-14). When you select PRGM_, it is copied to the cursor location. You may type the letters of an existing program name. You may also enter the name of a program you have not yet created. When encountered, the command executes the specified program and then returns to the calling program. Execution continues with the command following PRGM_programname. PRGM_programname RETURN (PRGM CTL, item 0) quits the subroutine and returns to the calling program (pages 10-14), even if it is encountered within nested loops. (Any loops are ended.) There is an implied RETURN at the end of any program called as a subroutine. Within the main program, RETURN stops program execution and returns to the Home screen. STOP (PRGM CTL, item A) stops execution of a program and returns you to the Home screen. STOP is optional at the end of a program. There is an implied stop at the end of the main program that is being executed. 10-10 Programming