H8SX1648 Datasheet, PDF (730/1472 Pages) Renesas Technology Corp – Renesas 32-Bit CISC Microcomputer H8SX Family / H8SX/1600 Series

Section 13 I/O Ports
13.4 Usage Notes
13.4.1 Notes on Input Buffer Control Register (ICR) Setting
1. When the ICR setting is changed, the LSI may malfunction due to an edge occurred internally
according to the pin state. Before changing the ICR setting, fix the pin state high or disable the
input function corresponding to the pin by the on-chip peripheral module settings.
2. If an input is enabled by setting ICR while multiple input functions are assigned to the pin, the
pin state is reflected in all the inputs. Care must be taken for each module settings for unused
input functions.
3. When a pin is used as an output, data to be output from the pin will be latched as the pin state
if the input function corresponding to the pin is enabled. To use the pin as an output, disable
the input function for the pin by setting ICR.
13.4.2 Notes on Port Function Control Register (PFCR) Settings
1. Port function controller controls the I/O port.
Before enabling a port function, select the input/output destination.
2. When changing input pins, this LSI may malfunction due to the internal edge generated by the
pin level difference before and after the change.
• To change input pins, the following procedure must be performed.
A. Disable the input function by the corresponding on-chip peripheral module settings
B. Select another input pin by PFCR
C. Enable its input function by the corresponding on-chip peripheral module settings
3. If a pin function has both a select bit that modifies the input/output destination and an enable
bit that enables the pin function, first specify the input/output destination by the selection bit
and then enable the pin function by the enable bit.
4. The value of the PCJKE bit must be set during the initial setting immediately after a power-on.
Set the PCJKE bit first and then set other bits in PFCR as required.
5. Do not change the value of the PCJKE bit once it has been set.
Rev. 2.00 Jul. 31, 2008 Page 700 of 1438
REJ09B0365-0200