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Why can't I read the value from Port B of H8/3664H using digital input?

Latest Updated:03/18/2009

Question:

I cannot read the correct value from Port B on the H8/3664H when using it as a digital input. Bit 0 ( Port B.0 ) always reads back as 0.

Answer:

This is because Port B is also the A/D input port. The A/D is always selected as Port B by default and any bit that is selected as the A/D input will always read back 0 when read as digital I/O. To read Port B as a digital input please select a different pin as the A/D input.
Suitable Products
H8/300H Tiny