0041 0000 ; BRK AND NMI ENTRY POINTS TO TIM
0042 0000 ; ——————————-
0043 0000 ;
0044 0000 ; TIM IS NORMALLY ENTERED WHEN A ‘BRK’ INSTRUKTION IS
0045 0000 ; ENCOUNTERED DURING PROGRAM EXECUTION. AT THAT
0046 0000 ; TIME CPU REGISTERS ARE OUTPUT: PC F A X Y SP
0047 0000 ; AND CONTROL IS GIVEN TO THE KEYBOARD.
0048 0000 ; USER MAY ENTER TIM BY PROGRAMMED BRK OR INDUCED NMI. NMI
0049 0000 ; ENTRIES CAUSE A ‘#’ TO PRECEDE THE ‘.’ IN THE CPU REGISTER
0050 0000 ; PRINTOUT FORMAT
0051 0000 ;
0052 0000 ; NON-BRK INTRO (EXTERNAL DEVICE) INTERRUPT HANDLING
0053 0000 ; ————————————————–
0054 0000 ;
0055 0000 ; A NON-BRK INTRO INTERRUPT CAUSES AN INDIRECT JUMP TO THE ADDRESS
0056 0000 ; LOCATED AT ‘UINT’ (HEX FFF8). THIS LOCATION CAN BE SET
0057 0000 ; USING THE ALTER CMD, OR LOADED AUTOMATICALLY IN PAPER TAPE
0058 0000 ; FROM WITH THE LH CMD IF THE USER ASSIGNS HIS INTRO INTERRUPT
0059 0000 ; VECTOR TO $FFF8 IN THE SOURCE ASSEMBLY PROGRAM.
0060 0000 ; IF NOT RESET BY THE USER, UINT IS SET TO CAUSE EXTERNAL
0061 0000 ; DEVICE INTERRUPTS TO ENTER TIM AS NMI’S. I.E.,
0062 0000 ; IF A NMI OCOURS WITHOUT AN INDUCED NMI SIGNAL, IT IS
0063 0000 ; AN EXTERNAL DEVICE INTERRUPT.
0064 0000 ;
0065 0000 ; SETTING AND RESETTING PROGRAM BREAKPOINTS
0066 0000 ; —————————————–
0067 0000 ;
0068 0000 ; BREAKPOINTS ARE SET AND RESET USING THE MEMORY DISPLAY
0069 0000 ; AND ALTER COMMANDS. BRK HAS A ’00’ OPERATION CODE.
0070 0000 ; TO SET A BREAKPOINT SIMPLY DISPLAY THE MEMORY LOCATION
0071 0000 ; (FIRST INSTRUCTION BYTE) AT WHICH THE BREAKPOINT IS
0072 0000 ; TO BE PLACED THEN ALTER THE LOCATION TO ’00’. THERE IS
0073 0000 ; NO LIMIT TO THE NUMBER OF BREAKPOINTS THAT CAN BE
0074 0000 ; ACTIVE AT ONE TIME.
0075 0000 ; TO RESET A BREAKPOINT, RESTORE THE ALTERED MEMORY LOCATION
0076 0000 ; TO ITS ORIGINAL VALUE.
0077 0000 ; WHEN AND IF A BREAKPOINT IS ENCOUNTERED DURING EXECUTION,
0078 0000 ; THE BREAKPOINT DATA PRECEDEC BY AN ‘:’ IS DISPLAYED.
0079 0000 ; THE PROGRAM COUNTER VALUE DISPLAYED IS THE BRK
0080 0000 ; INSTRUCTION LOCATION + 1.