
218
Agere Systems Inc.
T8302 Internet Protocol Telephone
Advanced RISC Machine (
ARM
)
Data Sheet
July 2001
16 Parallel Peripheral Interface (PPI)
(continued)
16.2 PPI Registers
Table 188. PPI Parallel I/O Controller Register Map
16.2.1 PPI Data Direction Register
The
PPI port data direction register
contains one bit for each of the general-purpose I/O pins. If a bit in the
PPI port data direction register
is a 1, the corresponding pin is an output; otherwise, it is an input. Table 189
below shows the format of the
PPI port data direction register
. On all resets, all bits in the
PPI port data direc-
tion register
are cleared to zeros, indicating inputs.
Table 189. PPI Data Direction Register
16.3 PPI Port Data Register
The
PPI port data register
reads general-purpose input pins and writes general-purpose output pins. When
the
PPI port data register
is read, the bits configured as outputs reflect the value previously written to the register. The
bits configured as inputs reflect the (possibly inverted) level on the input pin.
When a new value is written to
the
PPI port data register
, the corresponding pins that are programmed as general
purpose outputs change to or stay at this value. Register bits configured as inputs do not respond to writes to the
register. Table 190 below shows the format of the
PPI port data register
. On reset, all
PPI port data register
bits
are cleared to zeros.
Register
Address
0xE000 6000
0xE000 6004
0xE000 6008
0xE000 600C
0xE000 6010
0xE000 6014
0xE000 6018
0xE000 601C
0xE000 6020
0xE000 6024:0xE000 6036
PPI port data direction register
(see Table 189 on page 218)
.
PPI port data register
(see Table 190 on page 219)
.
PPI port interrupt enable register
(see Table 191 on page 219)
.
PPI port sense register
(see Table 192 on page 220)
.
PPI port polarity register
(see Table 193 on page 220)
.
PPI port pull-up enable register
(see Table 194 on page 221)
.
Reserved.
PPI port data clear register
(see Table 195 on page 221)
.
PPI port data set register
(see Table 196 on page 222)
.
Reserved.
Address 0xE000 6000
31:16
RSVD
Bit #
Name
15:
0
PD[15:
0
]
Bit #
31:16
15:
0
Name
RSVD
PD[15:
0
]
Description
Reserved.
Data direction bits.
If 1, it indicates an output.
If 0, it indicates an input.