CS4201 Datasheet, PDF (33/68 Pages) Cirrus Logic – CrystalClear Audio Codec 97 with headphone Amplifier

CS4201
4.19 GPIO Pin Polarity/Type Configuration Register (Index 4Eh)
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
1
1
1
1
1
1
1
1
1
1
1
1
1
1 GP1 GP0
GP[1:0]
GPIO Pin Configuration. This register defines the GPIO input polarity (0 = Active Low,
1 = Active High) when a GPIO pin is configured as an input. The GP[1:0] bits define the GPIO
output type (0 = CMOS, 1 = OPEN-DRAIN) when a GPIO pin is configured as an output. The
GC[1:0] bits in the GPIO Pin Configuration Register (Index 4Ch) define the GPIO pins as in-
puts or outputs. See Table 9 for the various GPIO configurations.
Default
FFFFh
After a Cold Reset or a modem Register Reset this register defaults to all 1’s. The upper 14 bits of this register al-
ways return ‘1’.
GCx GPx Function Configuration
0 0 Output
CMOS Drive
0 1 Output
Open Drain
1 0 Input
Active Low
1 1 Input Active High (default)
Table 9. GPIO Input/Output Configurations
4.20 GPIO Pin Sticky Register (Index 50h)
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
0
0
0
0
0
0
0
0
0
0
0
0
0
0 GS1 GS0
GS[1:0]
GPIO Pin Sticky. This register defines the GPIO input type (0 = not sticky, 1 = sticky) when a
GPIO pin is configured as an input. The GPIO pin status of an input configured as “sticky” is
‘cleared’ by writing a ‘0’ to the corresponding bit of the GPIO Pin Status Register (Index 54h),
and by reset.
Default
0000h
After a Cold Reset or a modem Register Reset this register defaults to all 0’s, specifying “non-sticky”. “Sticky” is de-
fined as edge sensitive, “non-sticky” as level sensitive. The upper 14 bits of this register always return ‘0’.
DS483PP3
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