Digital Electronics Objectives Part 23
441 . I/O ports can be accessed by direct method is 256.
442 . I/O ports can be accessed by memory mapped method is 32 K.
443 . TRAP interrupt has the highest priority.
444 . INTR interrupt has the lowest priority.
445 . If interrupt service request have been received from all of the following interrupts, then RST 5.5 will be serviced last.
446 . If interrupt service requests have been received from all of the following interrupts, then RST 7.5 will be serviced first.
447 . RST 5.5, RST 6.5 and RST 7.5 are vectored interrupts.
448 . TRAP interrupt is unmaskable interrupt.
449 . If instruction RST is written in a program the program will jump to location 0028 H.
450 . TRAP interrupt is triggered program control is transferred to location 0024 H.
451 . The RST 5.5 interrupt service routine start from location 002 CH.
452 . An interrup service request is serviced after the execution of the current instruction is compacted.
453 . Even after a Reset operation TRAP interrupts remain enabled.
454 . In order to enable RST 5.5, RST 6.5 and RST 7.5 interrupts, EI and SIM instruction are needed.
455 . In order to enable interrupt, EI only needed.
456 . In order to enable TRAP none of the instruction is needed.
457 . A RIM instruction is used to Read in the serial input data and read in status of pending interrupts, if any.
458 . Refer to program in Fig.64. the microprocessor is interrupted while executing MOV instruction at location 0210 H. The location at which contents of register D are stored is 054 FH.
459 . Refer to program in Fig.64. the microprocessor is interrupted while executing MOV instruction at location 0210 H. The location at which contents of register D are stored is 054 FH.
460 . For the condition of Q 458. 0.211 H is the memory address on the stack, when the program is interrupted.
