Motorola DSP56012 Manuale Utente

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7-4
DSP56012 User’s Manual 
MOTOROLA
GPIO
GPIO Register (GPIOR)
7.3.1
GPIOR Data Bits (GD[7:0])—Bits 7–0
The read/write GPIO Data bits (GD[7:0]) are used to read from or write to the 
corresponding GPIO[7:0] pins. If the GPIOx pin is defined as an input, the GDx bit 
will reflect the logic value present on the GPIOx pin. If the GPIOx pin is defined as an 
output, the GPIOx pin will reflect the value written to the GDx bit. The GD[7:0] bits 
are cleared during hardware reset and software reset.
7.3.2
GPIOR Data Direction Bits (GDD[7:0])—Bits 15–8
The read/write GPIO Data Direction bits (GDD[7:0]) select the direction of data 
transfer for each of the GPIO[7:0] pins (see 
). When the GDDx bit is cleared, 
the corresponding GPIOx pin is defined as an input. When the GDDx bit is set, the 
corresponding GPIOx pin is defined as an output. The GDD[7:0] bits are cleared 
during hardware reset and software reset.
7.3.3
GPIOR Control Bits (GC[7:0])—Bits 23–16
The read/write GPIO Control bits (GC[7:0]) select the type of output buffer for each 
of the GPIO[7:0] pins when the pins are defined as outputs, and select whether or not 
the input buffer is connected to the pin when the pin is defined as an input. 
Table 7-1   
GPIO Pin Configuration
GDDx
GCx
GPIO Pin Definition
0
0
Disconnected
0
1
Input
1
0
Standard active high/active low output
1
1
Open-drain output