Rabbit Rabbit 4000, User Manual

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90 Rabbit 4000 Microprocessor User’s Manual
11.1.2 Registers
11.2 Dependencies
11.2.1 I/O Pins
Parallel Port D uses pins PD0 through PD7. These pins can be used individually as data
inputs or outputs; as serial port transmit and receive for Serial Ports A, B, E, and F; as clocks
for Serial Ports C–F; as external I/O strobes; or as outputs for the PWM and Timer C
peripherals. In addition, Parallel Port D acts as the upper byte of the data bus (D[15:8])
when 16-bit addressing is enabled. The input capture peripheral can also watch pins PD7,
PD5, PD3, and PD1.
All pins are set as inputs on startup.
The individual bits can be set to be open-drain via PDDCR.
See the associated peripheral chapters for details on how they use Parallel Port D.
11.2.2 Clocks
All outputs on Parallel Port D are clocked by the peripheral clock unless changed in PDCR,
where the option of updating the Parallel Port D pins can be synchronized to the output of
Timer A1, Timer B1, or Timer B2.
Register Name Mnemonic I/O Address R/W Reset
Port D Data Register PDDR 0x0060 R/W xxxxxxxx
Port D Alternate Low Register PDALR 0x0062 R/W 00000000
Port D Alternate High Register PDAHR 0x0063 R/W 00000000
Port D Control Register PDCR 0x0064 R/W xx00xx00
Port D Function Register PDFR 0x0065 R/W xxxxxxxx
Port D Drive Control Register PDDCR 0x0066 R/W xxxxxxxx
Port D Data Direction Register PDDDR 0x0067 R/W 00000000
Port D Bit 0 Register PDB0R 0x0068 W xxxxxxxx
Port D Bit 1 Register PDB1R 0x0069 W xxxxxxxx
Port D Bit 2 Register PDB2R 0x006A W xxxxxxxx
Port D Bit 3 Register PDB3R 0x006B W xxxxxxxx
Port D Bit 4 Register PDB4R 0x006C W xxxxxxxx
Port D Bit 5 Register PDB5R 0x006D W xxxxxxxx
Port D Bit 6 Register PDB6R 0x006E W xxxxxxxx
Port D Bit 7 Register PDB7R 0x006F W xxxxxxxx