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(38D2) Why H output when I want to output L from P65/TXOUT1 if switch from IGBT?

Latest Updated:09/29/2006


(Timer)  Why is "H" sometimes output even though the user wants to output "L" from the P35/TXOUT1 pin when switching from IGBT output mode to general-purpose port output? [2006/09/29]


Cause: Because the port latch value has been changed to "1".
Example: When executing the read-modify-write instruction in byte units with SEB or CLB, etc. of port P3 while IGBT output is "H", output data "H" is read and the port latch value is changed to "1".
Countermeasures: Use the following procedure to switch the timer X output 1 selection bit.
1. Stop timer X (IGBT output (TXOUT1) becomes "L").
2. Write "0" to the P35 port latch.
3. Set the timer X output 1 selection bit to "0" (I/O port).
The above also applies to the P37/TXOUT2 pin. (#106381)
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