Digi Rabbit 5000, User Manual

Page: 109 / 414

Chapter 11 Parallel Port D 109
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. 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.
11.2.3 Other Registers
11.2.4 Interrupts
External interrupts can be accepted from pins PD1 or PD0; see Chapter 7 for more details.
Register Function
SACR, SBCR, SCCR,
SDCR, SECR, SFCR Select a Parallel Port D pin as serial data (and
optional clock) input.
ICS1R, ICS2R
Select a Parallel Port D pin as a start/stop condition
for Input Capture input.
QDCR
Select a Parallel Port D pin as a Quadrature Decoder
input.
I0CR, I1CR
Select a Parallel Port D pin as an external interrupt
input.
DMR0CR, DMR1CR
Select a Parallel Port D pin as an external DMA
request input.