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send thermistor temp down gpio pins

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hey guys.
my pic programmer guy has finaly finished the coding of my chip. i have asked him to send the thermister from my own pcb down the gpio pin of the banana pi.
i know that its a digital pin but that was the only pin that was linked to the pic chip, so i told him to convert the temperature into a time function so if the temp is 35.4c then he would make the gpio active for 354ms and then inactive for 1 second.

anyway i tried to make a bash script to read these delays and im failing.
it seems that i cannot read the pins that fast with my code.

instead of the expected millisecond count of around 300 im actualy getting between 1-3
could you explain to me whats wrong.

here is my code.
  1. #!/bin/bash
  2. gpio mode 1 in

  3. COUNTER=0
  4. Timeout=0

  5.          while gpio read 1 ; do
  6.                 sleep 0.001
  7.                 if [ $Timeout -gt 2000 ]; then
  8.                         echo "error $Timeout"
  9.                         exit 1
  10.                 fi

  11.                 Timeout=$((Timeout+1))
  12.          done

  13. Timeout=0

  14.          while gpio read 0 ; do
  15.                 sleep 0.001
  16.                                 if [ $Timeout -gt 2000 ]; then
  17.                         echo "error $Timeout"
  18.                         exit 1
  19.                 fi
  20.                 Timeout=$((Timeout+1))
  21.          done

  22. Timeout=0

  23.          while gpio read 1 ; do
  24.                 sleep 0.001
  27.                 if [ $Timeout -gt 2000 ]; then
  28.                         echo "error $Timeout"
  29.                         exit 1
  30.                 fi

  31.                 Timeout=$((Timeout+1))
  33.          done

  34. echo $Timeout
Copy the Code

the first while loop is to wait untill the 1 second inactive pin
the second loop is to wait until the pin becomes active once again
and finaly the last loop will count the milliseconds until that pin becomes inactive

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