Hitachi H8/3022 Hardware Manual page 187

When port B pins are used for TPC output, PBDR stores output data for TPC output groups 2 and
3. If a bit in the next data enable register (NDERB) is set to 1, the corresponding PBDR bit cannot
be written. In this case, PBDR can be updated only when data is transferred from NDRB.
7.11.3 Pin Functions
The port B pins are also used for TPC output (TP , TP to TP ), ITU input/output (TIOCB ,
15 13 8 4
), and ADTRG input. Table 7-18
TIOCB , TIOCA , TIOCA ) and output (TOCXB , TOCXA
3 4 3 4 4
describes the selection of pin functions.
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