
Rev. 2.0, 09/02, page 550 of 732
17.1.11
High-Current Port Control Register (PPCR
)
The high-current port control register (PPCR) is an 8-bit readable/writable register that is used to
control six pins (PE9/TIOC3B/SCK3/
TRST
*,PE11/TIOC3D/RXD3/TDO*,
PE12/TIOC4A/TXD3/TCK*, PE13/TIOC4B/
MRES
, PE14/TIOC4C/DACK0,
PE15/TIOC4D/DACK1/
IRQOUT
) of the high-current ports.
This register is not supported in the emulator. Bits are always read as undefined in the emulator.
Note: * Only in the SH7145
Bit
Bit Name
Initial
Value
R/W
Description
7 to 1
All 0
R
Reserved
These bits are always read as 0, and should only be
written with 0.
0
MZIZE
0
R/W
High-current port high-impedance
This bit selects whether or not the high-current ports
are set to high-impedance regardless of the PFC
setting when detecting oscillation halt or in software
standby mode.
0: Set to high-impedance
1: Not set to high-impedance
If this bit is set to 1, the pin state is retained when
detecting oscillation halt.
For the pin state in software standby mode, refer to
Appendix A, Pin States.
17.2
Precautions for Use
1.
In this LSI, individual functions are available as multiplexed functions on multiple pins. This
approach is intended to increase the number of selectable pin functions and to allow the easier
design of boards. When the pin function controller (PFC) is used to select a function, only a
single pin can be specified for each function. If two or more pins are specified for one
function, the function will not work properly.
2.
When the port input is switched from a low level to the
DREQ
or the
IRQ
edge for the pins
that are multiplexed with input/output and
DREQ
or
IRQ
, the corresponding edge is detected.
3.
Do not set functions other than those specified in tables 17.13 and 17.14. Otherwise, correct
operation cannot be guaranteed.
4.
When pin functions are selected, set the port I/O registers (PBIOR and PDIORL) after setting
the port control registers (PBCR1, PBCR2, PDCRL1, and PDCRL2).