I/O Processor Registers
A-110
ADSP-2126x SHARC Processor Hardware Reference
Table A-33. Parallel Port Register (PPCTL) Bit Definitions
Bit
Name
Definition
Default
0
PPEN
Parallel Port Enable.
Enables if set, (= 1) or disables if
cleared, (= 0) the parallel port. Clearing this bit clears
FIFO and status. If an
RD
,
WR
, or ALE cycle has already
started, it completes normally before the port is disabled.
The parallel port is ready to transmit or receive 2 cycles
after enabling. An ALE cycle always occurs before the first
read or write cycle after PPEN is enabled.
0
5–1
PPDUR
Parallel Port Duration.
The duration of Parallel Port data
cycles is based on core-clock and controlled by these five
bits as follows:
00000 = Reserved
00001 = Reserved
00010 = 2 Wait States = 3 Core Clock Cycles;
66 MHz throughput
00011 = 3 Wait States = 4 Core Clock Cycles;
50 MHz throughput
00100 = 4 Wait States = 5 Core Clock Cycles;
40 MHz throughput
00101 = 5 Wait States = 6 Core Clock Cycles;
33 MHz throughput
...
11111 = 31 wait states; 6.25MHz throughput
Bit 1 = 1
Bit 2=1
Bit 3=1
Bit 4=0
Bit 5=1
6
PPBHC
Bus Hold Cycle.
Inserts a bus hold cycle at the end of
every access (read or write cycle) if set, (= 1) or no bus
hold cycle occurs if cleared, (= 0). During a BHC address
and/or data continue to be driven for one cycle.
1
7
PP16
Parallel Port External Data Width.
Selects the external
data width to 16 bits if set, (= 1) or 8 bits if cleared, (= 0).
0
8
PPDEN
Parallel Port DMA Enable.
Enables if set, (= 1) DMA on
the parallel port or disables DMA if cleared, (= 0). When
PPDEN is cleared, any DMA requests already in the pipe-
line complete, and no new DMA requests are made. This
does not affect FIFO status.
0
9
PPTRAN
Parallel Port Transmit/Receive Select.
Indicates if the
processor is reading from external memory if cleared, (= 0)
or writing to external memory if set, (= 1).
0
Содержание ADSP-21261 SHARC
Страница 30: ...Contents xxx ADSP 2126x SHARC Processor Hardware Reference ...
Страница 40: ...Register Diagram Conventions xl ADSP 2126x SHARC Processor Hardware Reference ...
Страница 58: ...Differences From Previous SHARCs 1 18 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 112: ...Secondary Processing Element PEy 2 54 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 178: ...Summary 3 66 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 204: ...DAG Instruction Summary 4 26 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 322: ...Setting Up DMA 7 32 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 436: ...SPORT Programming Examples 9 86 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 521: ...ADSP 2126x SHARC Processor Hardware Reference 11 31 Input Data Port rts IDP_ISR end ...
Страница 522: ...Input Data Port Programming Example 11 32 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 590: ...Timer Programming Examples 14 20 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 796: ...I O Processor Registers A 174 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 800: ...B 4 ADSP 2126x SHARC Processor Core Manual ...
Страница 846: ...Index I 36 ADSP 2126x SHARC Processor Hardware Reference ...