Hardware Interrupts in 8085......(Interrupts Contd)........

Hardware Interrupt:-
As i have already discussed that there are 6 interrupt pins in the microprocessor used as Hardware Interrrupts given below:
TRAP
RST7.5
RST6.5
RST5.5
INTR
INTA is not an interrupt. INTA is used by the Microprocessor for sending
 the acknowledgement. TRAP has highest priority and RST7.5 has second highest priority and so on.
The Vector address of these interrupts are given below:
                                          
1.TRAP:-It is non maskable edge and level triggered interrupt. TRAP has the highest priority and vectores interrupt. Edge and level triggered means that the TRAP must go high and remain high until it is acknowledged. In case of sudden power failure, it executes a ISR and send the data from main memory to backup memory.
As we know that TRAP can not be masked but it can be delayed using HOLD signal.
This interrupt transfers the microprocessor's control to location 0024H.
How a TRAP interrupt may be masked???
TRAP interrupts can only be masked by reseting the microprocessor. There is no other way to mask it.

2.RST7.5:-It has the second highest priority. It is maskable and edge level triggered interrupt. The vector address of this interrupt is 003CH. Edge sensitive means input goes high and no need to maintain high state until it is recognized.
How It may be masked??
It can also be reset or masked by reseting microprocessor. It can also be resetted by DI instruction.

3.RST6.5 and RST5.5:-These are level triggered and maskable interrupts. When RST6.5 pin is at logic 1, INTE flip-flop is set. RST 6.5 has third highest priority and RST 5.5 has fourth highest priority.
It can be masked by giving DI and SIM instructions or by reseting microprocessor.



4.INTR:-It is level triggered and maskable interrupt. It has the lowest priority. It can be disabled by reseting the microprocessor or by DI and SIM instruction.


The following sequence of events occurs when INTR signal goes high:
1. The 8085 checks the status of INTR signal during execution of each instruction.

2. If INTR signal is high, then 8085 complete its current instruction and sends active low interrupt acknowledge signal, if the interrupt is enabled.

3.On receiving the instruction, the 8085 save the address of next instruction on stack and execute received instruction.









31 comments:

  1. Vasuveer8 January 2013 at 00:36

    what is the vector add. for intr

    ReplyDelete
    Replies
    1. Unknown26 October 2013 at 04:05

      there is no fix address of intr ....there are fix address only for trap,rst 7.5,rst 6.5 nd rst 5.5.......
      if u want the intr vector address then mp sends an inta means interrupt acknoledgement to external hardware ...

      Delete
    2. Admin_ElitmusAdda25 November 2014 at 13:24

      INTR is a non vectored interrupt so it has no vectored address -_-

      Delete
    3. Unknown21 August 2016 at 16:11

      there is no vector address for INTR

      Delete
  2. Unknown1 May 2014 at 19:22

    the essential difference between traps and interupts is
    1) traps are synchronous and interrupts are asynchronous with the program.
    2) traps are asynchronous and interrupts are synchronous with the program.
    3) traps are synchronous and interrupts are asynchronous with the I/O devices.
    4) none of these.

    ReplyDelete
    Replies
    1. Unknown23 February 2016 at 04:49

      TRAP is also a Interrupt known as Hard ware Interrupt.so u can't differentiate b/w Trap & interrupt.

      Delete
  3. Unknown5 September 2015 at 02:42

    Is software interrupts are having highest priority or hardware interrupts.........?

    ReplyDelete
    Replies
    1. Unknown21 May 2016 at 22:42

      Hardware interrupts have higher priority than software interrupts.

      Delete
    2. Unknown21 May 2016 at 22:43

      Hardware interrupts have higher priority than software interrupts.

      Delete
  4. Unknown5 September 2015 at 02:42

    Is software interrupts are having highest priority or hardware interrupts.........?

    ReplyDelete
  5. prin4 November 2015 at 00:03

    what is the vector address for INTR??

    ReplyDelete
  6. Unknown25 February 2016 at 05:58

    INTR is non-vectored. It does not have a vector address

    ReplyDelete
  7. Unknown25 February 2016 at 05:59

    INTR is non-vectored. It does not have a vector address

    ReplyDelete
  8. Unknown13 March 2016 at 10:54

    why the names of the interrupts are RST 5.5, RST 6.5, RST 7.5? Why isn't it RST 1.5, RST 2.5 and so on. I'm concerned with the numbering.

    ReplyDelete
  9. Aman Dhakal13 May 2016 at 22:51

    what is vector address of RST 6.5 and 5.5??? :\

    ReplyDelete
    Replies
    1. Unknown14 November 2016 at 09:22

      This comment has been removed by the author.

      Delete
    2. Unknown14 November 2016 at 09:25

      for-6.5-
      6.5 x 8= 52
      52/16=quo-3 rem-4

      vectr addr- 0034
      i.e format is- 00

      Delete
  10. Unknown28 May 2016 at 19:30

    All this copied word to word from here - http://scanftree.com/microprocessor/Interrupts-In-8085

    ReplyDelete
  11. Unknown3 August 2016 at 20:20

    We know already INTR is not a Intrupt so has no vector address.only Intrupts(INTA,RST7.5 ,RST6.5,RST5.5) has vector address.

    ReplyDelete
  12. Unknown3 August 2016 at 20:38

    Dear Aman your answer is here
    To find vector address of any Intrupts have to do the following steps.
    Firs multiply intrupt with 8 and if the result is less than 16 we have to divide the resulted value by 8
    And if the result is greater than 16 we have to divide the resulted value by 16 .
    To find vector address of Intrupts 6.5
    Intrup number ×8
    6.5 ×8=44.0= 44
    Since 44 is greater than 15 therefore we have to divide 44 by 16 and we find
    16|44|2
    32
    -
    12
    We know that c= 12
    Therefore vector addres is 002CH(vector address of Intrupt6.5)
    H represents Hexa

    ReplyDelete
  13. Unknown3 August 2016 at 20:39

    Dear Aman your answer is here
    To find vector address of any Intrupts have to do the following steps.
    Firs multiply intrupt with 8 and if the result is less than 16 we have to divide the resulted value by 8
    And if the result is greater than 16 we have to divide the resulted value by 16 .
    To find vector address of Intrupts 6.5
    Intrup number ×8
    6.5 ×8=44.0= 44
    Since 44 is greater than 15 therefore we have to divide 44 by 16 and we find
    16|44|2
    32
    -
    12
    We know that c= 12
    Therefore vector addres is 002CH(vector address of Intrupt6.5)
    H represents Hexa

    ReplyDelete
  14. Unknown3 August 2016 at 20:43

    We know already INTR is not a Intrupt so has no vector address.only Intrupts(INTA,RST7.5 ,RST6.5,RST5.5) has vector address.

    ReplyDelete
  15. Unknown3 August 2016 at 20:43

    We know already INTR is not a Intrupt so has no vector address.only Intrupts(INTA,RST7.5 ,RST6.5,RST5.5) has vector address.

    ReplyDelete
  16. Unknown3 August 2016 at 20:45

    We know already INTR is not a Intrupt so has no vector address.only Intrupts(INTA,RST7.5 ,RST6.5,RST5.5) has vector address.

    ReplyDelete
  17. Unknown15 September 2016 at 11:20

    1. What is the highest priority?
    Trap or RST 6.5
    Hold priority is higher than trap priority. Is it correct or not ?

    ReplyDelete
  18. Unknown15 September 2016 at 11:21

    This comment has been removed by the author.

    ReplyDelete
  19. Pawan26 September 2017 at 19:47

    What is vectored interrupt

    ReplyDelete
  20. Pawan26 September 2017 at 19:48

    There is one software pin in 8085 m p.what is name of that pin

    ReplyDelete
  21. Pawan26 September 2017 at 19:49

    What is vectored interrupt

    ReplyDelete
  22. Bigg Boss31 January 2018 at 21:19

    Different Loading Schemes
    Relocation: Linking Concept
    Regular Expression and Regular Definition
    IEEE 802.11 Architecture
    Phases: Language processor (Toy compiler)
    8086 Pin Diagram
    80386 Architecture

    ReplyDelete