AnsweredAssumed Answered

Why does ATD1 appear to not work at all in MC9S12XEP100?

Question asked by Duane Carter on Mar 4, 2015
Latest reply on Mar 6, 2015 by Duane Carter

I configure both ATD0 and ATD1 in the same way from code ported from a system working with the MC9S12DP256.  All the register settings were modified in the port according to guidance in the S12 / S12XE compatibility guide (AN3469) and the S12XE reference manual (MC9S12XEP100RMV1). Signals connected to ATD0 inputs all result in expected A/D conversion values.  Nothing connected to ATD1 inputs comes close to correct.  In fact, all inputs yield a very similar result, a little less that the midrange of 10-bit, regardless of the voltage level of the input signal (5V A/D reference, inputs of 4.1V, 2.5V, ground, and floating open).

Outcomes