PD17012_15 Datasheet, PDF (91/320 Pages) Renesas Technology Corp – 4-BIT SINGLE-CHIP MICROCONTROLLERS WITH DIGITAL TUNING SYSTEM HARDWARE

µPD17012, 17P012
10.5.2 Use of output ports (P0C and P1C)
The output ports output the contents of the output latches.
The output data is set by executing an instruction, such as MOV, that writes the data to the port register
corresponding to the output port.
Write 1 to the port register to output a high level to the corresponding port; write 0 to output a low level.
Note, however, that the P0C3, P0C2, P0C1, and P0C0 pins are N-ch open-drain output pins and are floated
when a high level is output.
When an instruction, such as SKT, that reads the contents of the port register is read, the contents of the
output latch are read.
10.5.3 Status of output ports (P0C and P1C) on reset
(1) On power-on reset
The contents of the output latch are output.
Because the contents of the output latch are undefined, an undefined value is output for a fixed period (until
the output latch is initialized by program).
(2) On CE reset
The contents of the output latch are output.
The contents of the output latch are retained and the output data is not changed on CE reset.
(3) On execution of clock stop instruction
The contents of the output latch are output.
The contents of the output latch are retained and the output data is not changed on execution of the clock
stop instruction.
Therefore, initialize the output latch in the program as necessary.
(4) In halt status
The contents of the output latch are output.
The contents of the output latch are retained and the output data is not changed in the halt status.
Data Sheet U10101EJ4V0DS
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