CS4281 Datasheet, PDF (28/36 Pages) Cirrus Logic – CrystalClear PCI Audio interface

CS4281
CrystalClear™ PCI Audio Interface
EEDAT/GPIO2/PCGNT# - EEPROM Data Line / PC/PCI Grant, I/O
For expansion card designs, this is the data line for external serial EEPROM containing device
configuration data. When used with an external EEPROM, a 4.7 kΩ pullup resistor is required.
In motherboard designs using PC/PCI, this pin is the PC/PCI serialized grant input. In designs
with neither of the above requirements, this pin can be used as a general purpose input or open
drain output (GPIO2).
EECLK/GPOUT/PCREQ# - EEPROM Clock Line / PC/PCI Request, Output
For expansion card designs, this is the clock line for external serial EEPROM containing
device configuration data. In motherboard designs using PC/PCI, this pin is the PC/PCI
serialized request output. In designs with neither of the above requirements, this pin can be
used as a general purpose output pin (GPOUT).
GPIO3 - General Purpose Input/Output 3, I/O
A general purpose I/O pin that is powered off the PCI power supply. Therefore, this pin does
not support PME# control from the AC link during D3_cold. This pin powers up in a high
impedance state providing backward compatibility. All general purpose I/O left unused must be
tied high through its own 10 kΩ resistor.
VOLUP - Volume-Up Button, Input
This pin is the volume-up button control input. This pin may also be used as a general purpose
input if its primary function is not needed. Due to the internal 20 kΩ pull-up resistor, if
VOLUP is unconnected, it will be pulled to its inactive state.
VOLDN - Volume-Down Button, Input
This pin is the volume-down button control input. This pin may also be used as a general
purpose input if its primary function is not needed. Due to the internal 20 kΩ pull-up resistor, if
VOLDN is unconnected, it will be pulled to its inactive state.
Clock / Miscellaneous
IRQ[A:C] - ISA interrupt pins, Outputs
These pins can be used in DOS legacy-compatibility mode to bypass the PCI interrupt and use
an ISA interrupt directly. Using these pins can preserve the multi-drop capability of the PCI
interrupt at the expense of another interrupt line. These pins power up high impedance for
backwards compatibility.
CRYVDD - DLL Power Supply
Power pin for internal delay-locked loop. This pin must be connected to a nominal +3.3 Volts.
CRYGND - DLL Ground Supply
Ground pin for internal delay-locked loop.
JACX, JACY, JBCX, JBCY - Joystick A and B X/Y Coordinates, I/O
These pins are the 4 axis coordinates for the joystick port.
JAB1, JAB2, JBB1, JBB2 - Joystick A and B Button Inputs, Input
These pins are the 4 button switch inputs for the joystick port.
CIRRUS LOGIC PRODUCT DATA SHEET
28
DS308PP4