Pulsin on multipins

Hi Guys ,
I have need to do pulsin on a device that has 18 inputs connected to sensors the changes are generally large and updated every 2 mins. so basicly a status summery of the sensors is done

the code would be the same with only the array varable storing the change for each sensor

I thought using the nice method hendric showing of using lookup , with an port offset would work , but sadly not for pulsin as i am getting rubbish on readings which are above 15
, i think its cos the offset number from porta is larger value than 15 and pulsin has a value limit at 15 ????

Can anyone advise how to solve this prob with multi inputs with pulsin or am i incorrect ???


Cheers

Sheldon

Code:

---


Eg

for T = 0 to 17

  lookup T [ 9,11,13,16,18,22,1,4,6,8,26,27,28,25,23,21,32,34], Portoffset  ' Sensor input 1 - 18
 
    pulsin PORTA.0[PortOffset],1,Leader

 Sensor(T) = Leader

Next T

---

Sheldon,

What's happening there is ... it will look at the state of the specified pin, and use either 0 or 1 for the pulsin pin, which is usually PORTB.0 or PORTB.1 depending on the chip being used.

So let's say T = 3, then the LOOKUP returns 16.
An offset of 16 from PORTA.0 is PORTC.0, so it gets the state of that pin (0 or 1).
If PORTC.0 = 0, it does the PULSIN on PORTB.0.
If PORTC.0 = 1, it does the PULSIN on PORTB.1.

There's probably a hundred ways to accomplish it, but here's an untested/not compiled thought.

Code:

---

FOR T = 0 TO 17
    lookup T [ 9,11,13,16,18,22,1,4,6,8,26,27,28,25,23,21,32,34], Portoffset  ' Sensor input 1 - 18
    Leader = 0
    IF PORTA.0[PortOffset] = 0 THEN
        WHILE PORTA.0[PortOffset] = 0 : WEND  ; Wait for start of pulse
        WHILE PORTA.0[PortOffset] = 1        ; Measure Pulse Width
          Leader = Leader + 1
          PAUSEUS 5                          ; Adjust loop timing to your needs
        WEND
    ELSE
        ; error, pin was not low to start
    ENDIF

    Sensor(T) = Leader                        ; Store Result
NEXT T

---

thanks darrel, that worked , i also added a timeout .

You must have redone pulsin, rctime others commands , in replacement code many times , a code equivalent link page to those code examples would be handy if they were one place for a reference

Cheers

Sheldon