HD64F38024HV Datasheet, PDF (255/684 Pages) Renesas Technology Corp – Hardware Manual Renesas 8-Bit Single-Chip Microcomputer H8 Family/H8/300L Super Low Power Series

Section 8 I/O Ports
from 1 to 0 only when the PIOFF bit is cleared to 0. Also, if a large current flow is
required, the PIOFF bit should be set to 1 and all the port data bits set to 1. Then clear
PIOFF to 0 and, after allowing 30 clock cycles to permit stabilization of the voltage
boost circuit, clear the port data bits to 0. If time is not provided to allow the voltage
boost circuit to stabilize, it will not be possible to produce a large current flow. There are
no such restrictions when setting port data bits from 0 to 1, regardless of the size of the
current flow. To shut down the voltage boost circuit, set PIOFF to 1 after programming
the port data bits. An example of the sequence of steps is provided below.
(Example Procedure) Shutting Down the in the Watch Mode without a Large Current
Flow to Port 9
Other operation
PIOFF = 0 (voltage boost circuit on)
PDR9 operation or other operation
PIOFF = 1 (voltage boost circuit off)
Execute SLEEP instruction
Watch mode
Cancel watch mode
Bit 2—Reserved
This bit is reserved; it can only be written with 0.
Bits 1 and 0—P9n/PWM Pin Function Switches
These pins select whether pin P9n/PWMn+1 is used as P9n or as PWMn+1.
Bit n
WKPn+1
0
1
Description
Functions as P9n output pin
Functions as PWMn+1 output pin
(initial value)
(n = 0 or 1)
Rev. 8.00 Mar. 09, 2010 Page 233 of 658
REJ09B0042-0800