KA12 strange behaviour


I purchased a KA12 SHIELD and it has a strange behaviour.
When i plug a potentiometer directly on the arduino board Analogic input send value 636.
When i use the shield and launch the example, strange values are measured:

  • when i connect nothing to the shield values of inputs 1 to 24 are equal to 0. It’s ok
  • when i connect the potentiometer to pin 1 of the shield. Values of ka12_read(19) to ka12_read(24 are equal to 621). Other values are 0
  • when i connect the potentiometer to pin 2 of the shield. Values of ka12_read(19)=158, ka12_read(20)=638 and 12_read(21) to ka12_read(24) are equal to 158. Other values are 0. Idem when i connect potentiometer on pins 3 to 6.
    -When i connect potentiometer alternatively on pin 7 to 24 on the shield. values of ka12_read(1) to ka12_read(18) are respectively equal to 636. These pins seem to have a correct behaviour.

Have you got a solution for this problem