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Intterupt not working...

natur3 t0mAt0

Hi,

I'm using a timer and external interrupt to detect the pulse, i can set the timer to run for 5 secs and loop back. But the program cannot vector to the external interrupt. This is my interrupt configurations and routine.

;********************************************
;-----------INTERRUPTS CONFIGURATIONS--------
;********************************************
MOV IE,#8CH
MOV SWCINT,#000H
MOV EIE1,#000H
MOV EIE2,#000H
MOV EIP1,#000H
MOV EIP2,#000H
MOV IP,#08H

;****************************
;-Timer 1 Overflow Interrupt-
;****************************
T1_INT:    CLR TF1        ; Clear overflow flag
          MOV TH1,#0D0H
          MOV TL1,#0A0H
          RETI

;**********************
;-External Interrupt 1-
;**********************
EX_INT:    INC 40H         ; Increment 40H
          RETI

Does the input to the external interrupt need to be digital? Any advice would be nice... Thanks in advance.

Parents
  • 0 in reply to natur3 t0mAt0

    The concept is called a running average.

    You use the time between beat 5 and 1 (4 periods) to emit a bmp.

    Then you use the time between beat 6 and 2 (4 periods) to emit a bmp.

    Then you use the time between beat 7 and 3 (4 periods) to emit a bmp.

    The first output will not be available until after you have detected 5 heart beats. Then, the display may update for every new heart beat detected.

    However, since a normal person at the best has a rest pulse just under 30 and normally in the 50-70 bpm, you can ignore the concept of a running average.

    If you take the time between 5 beats, a pulse of 28 bmp would give the first result after 9-11 seconds and then a new value every 9 seconds.

    With a more normal pulse of 60, the first value would be available afer 4-5 seconds, with a new update every 4 seconds.

    A young person at very hard load would with a pulse of 200 get a first value after 1.2-1.5 seconds, and a new update every 1.2 seconds.

Reply
  • 0 in reply to natur3 t0mAt0

    The concept is called a running average.

    You use the time between beat 5 and 1 (4 periods) to emit a bmp.

    Then you use the time between beat 6 and 2 (4 periods) to emit a bmp.

    Then you use the time between beat 7 and 3 (4 periods) to emit a bmp.

    The first output will not be available until after you have detected 5 heart beats. Then, the display may update for every new heart beat detected.

    However, since a normal person at the best has a rest pulse just under 30 and normally in the 50-70 bpm, you can ignore the concept of a running average.

    If you take the time between 5 beats, a pulse of 28 bmp would give the first result after 9-11 seconds and then a new value every 9 seconds.

    With a more normal pulse of 60, the first value would be available afer 4-5 seconds, with a new update every 4 seconds.

    A young person at very hard load would with a pulse of 200 get a first value after 1.2-1.5 seconds, and a new update every 1.2 seconds.

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