HD6475328CG Datasheet, PDF (191/459 Pages) Hitachi Semiconductor – Manual Gives a Hardware Description

1. Port 9 Data Direction Register (P9DDR)—H'FFFE
Bit
Initial value
Read/Write
7
6
5
4
3
2
1
0
P97DDR P96DDR P95DDR P94DDR P93DDR P92DDR P91DDR P90DDR
0
0
0
0
0
0
0
0
W
W
W
W
W
W
W
W
P9DDR is an 8-bit register that selects the direction of each pin in port 9. A pin functions as an
output pin if the corresponding bit in P9DDR is set to “1,” and as an input pin if the bit is cleared
to “0.”
P9DDR can be written but not read. An attempt to read this register does not cause an error, but
all bits are read as “1,” regardless of their true values.
At a reset and in the hardware standby mode, P9DDR is initialized to H'00, setting all pins for
input. P9DDR is not initialized in the software standby mode, so if a P9DDR bit is set to “1”
when the chip enters the software standby mode, the corresponding pin continues to output the
value in the port 9 data register.
A transition to the software standby mode initializes the on-chip supporting modules, so any pins
of port 9 that were being used by an on-chip module (example: free-running timer output) when
the transition occurs revert to general-purpose input or output, controlled by P9DDR and P9DR.
2. Port 9 Data Register (P9DR)—H'FFFF
Bit
Initial value
Read/Write
7
P97
0
R/W
6
P96
0
R/W
5
P95
0
R/W
4
P94
0
R/W
3
P93
0
R/W
2
P92
0
R/W
1
P91
0
R/W
0
P90
0
R/W
P9DR is an 8-bit register containing the data for pins P97 to P90. When the CPU reads P9DR, for
output pins it reads the value in the P9DR latch, but for input pins, it obtains the pin status directly.
9.10.3 Pin Functions
The pin functions of port 9 are the same in all MCU operating modes. As figure 9-21 indicated,
these pins are used for output of on-chip timer signals and for input and output of serial data and
clock signals as well as for general-purpose input and output. Specifically, they carry output
signals for free-running timers 2 and 3, output signals for the pulse-width modulation (PWM)
timer, and input and output signals for the serial communication interface.
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