SH7052 Datasheet, PDF (703/919 Pages) Renesas Technology Corp – SuperHTM RISC engine

When a pin functions as a general output, if a value is written to PGDR, that value is output
directly from the pin, and if PGDR is read, the register value is returned directly regardless of the
pin state.
When a pin functions as a general input, if PGDR is read the pin state, not the register value, is
returned directly. If a value is written to PGDR, although that value is written into PGDR it does
not affect the pin state. Table 19.14 summarizes port G data register read/write operations.
PGDR is initialized to H'0000 by a power-on reset (excluding a WDT power-on reset), and in
hardware standby mode. It is not initialized in software standby mode or sleep mode.
• Bits 15 to 4—Reserved: These bits always read 0. The write value should always be 0.
Table 19.14 Port G Data Register (PGDR) Read/Write Operations
Bits 3 to 0:
PGIOR
Pin Function
0
General input
Other than
general input
1
General output
Other than
general output
Read
Pin state
Pin state
PGDR value
PGDR value
Write
Value is written to PGDR, but does not affect pin
state
Value is written to PGDR, but does not affect pin
state
Write value is output from pin
Value is written to PGDR, but does not affect pin
state
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