Port Control Register (Pcr); Figure 7-22 Gpio/Essi Port Organization; Figure 7-23 Port Control Register (Pcr) - Motorola DSP56305 User Manual

GPIO
7.6.1

Port Control Register (PCR)

The read/write twenty-four-bit Port Control Register(PCR) controls the functionality of
the ESSI/GPIO signals. Each of the PC[5:0] bits controls the functionality of the
corresponding port signal. When a PC[i] bit is set, the corresponding port signal is
configured as a ESSI signal. When a PC[i] bit is cleared, the corresponding port signal is
configured as a GPIO signal. Either a hardware reset signal or a software reset
instruction clear all PCR bits.
7 6 5
PC5
STDn
13
15 14
21
23 22
Reserved Bit, Read As Zero, Should Be Written With Zero For Future Compatibility
MOTOROLA
6
DSP56305
Port C
per pin
ESSI0

Figure 7-22 GPIO/ESSI Port Organization

4 3 2
PC4 PC3
PC2
SRDn SCKn SCKn2 SCKn1 SCKn0
12 11 10
20 19 18

Figure 7-23 Port Control Register (PCR)

DSP56305 User's Manual
Enhanced Synchronous Serial Interface (ESSI)
GPIO/ESSI Selection and GPIO Usage
GPIO
1 0
0 = GPIO, 1 = ESSI
PC1 PC0
PCRC: ESSI0, X:$FFFFBF
PCRD: ESSI1, X:$FFFFAF
9 8
17 16
6
Port D
per pin
ESSI1
AA0688
AA1426
7-53