ADSP-BF50x Blackfin Processor Hardware Reference
20-25
Parallel Peripheral Interface
PPI Registers
The PPI has five memory-mapped registers (MMRs) that regulate its oper-
ation. These registers are the PPI control register (
PPI_CONTROL
), the PPI
status register (
PPI_STATUS
), the delay count register (
PPI_DELAY
), the
transfer count register (
PPI_COUNT
), and the lines per frame register
(
PPI_FRAME
).
Descriptions and bit diagrams for each of these MMRs are provided in the
following sections.
PPI Control Register (PPI_CONTROL)
The
PPI_CONTROL
register configures the PPI for operating mode, control
signal polarities, and data width of the port. See
Figure 20-13
for a bit dia-
gram of this MMR.
The
POLC
and
POLS
bits allow for selective signal inversion of the
PPI_CLK
and
PPI_FS1
/
PPI_FS2
signals, respectively. This provides a mechanism to
connect to data sources and receivers with a wide array of control signal
polarities. Often, the remote data source/receiver also offers configurable
signal polarities, so the
POLC
and
POLS
bits simply add increased flexibility.
The
DLEN[2:0]
field is programmed to specify the width of the PPI port in
any mode. Note any width from 8 to 16 bits is supported, with the excep-
tion of a 9-bit port width. Any pins unused by the PPI as a result of the
DLEN
setting are free for use in their other functions.
In ITU-R 656 modes, the
DLEN
field should not be configured for
anything greater than a 10-bit port width. If it is, the PPI will
reserve extra pins, making them unusable by other peripherals.
The
SKIP_EN
bit, when set, enables the selective skipping of data elements
being read in through the PPI. By ignoring data elements, the PPI is able
to conserve DMA bandwidth.
Summary of Contents for EZ-KIT Lite ADSP-BF506F
Page 50: ...Contents l ADSP BF50x Blackfin Processor Hardware Reference ...
Page 92: ...Development Tools 1 30 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 110: ...Interface Overview 3 12 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 236: ...Internal Flash Memory Control Registers 6 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 650: ...Programming Examples 15 56 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 804: ...Programming Examples 17 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1194: ...Programming Examples 24 90 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1256: ...ACM Registers A 50 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1264: ...Boundary Scan Architecture B 8 ADSP BF50x Blackfin Processor Hardware Reference ...