CS4239 Datasheet, PDF (87/98 Pages) Cirrus Logic – CrystalClear™ Portable ISA Audio System

CS4239
CrystalClear^TM Portable ISA Audio System
Joystick Interface
JACX, JACY - Joystick A Coordinates, Input
These pins are the X/Y coordinates for Joystick A. They should have a 5.6 nF capacitor to
ground and a 2.2 kΩ resistor to the joystick connector pins 3 and 6, respectively.
JAB1, JAB2 - Joystick A Buttons, Input - Internal Pullups
These pins are the switch inputs for Joystick A. They should be connected to joystick connector
pins 2 and 7, respectively; as well as have a 1 nF capacitor to ground.
JBCX, JBCY - Joystick B Coordinates, Input
These pins and are the X/Y coordinates for the second joystick, Joystick B. They should have a
5.6 nF capacitor to ground and a 2.2 kΩ resistor to the joystick connector pins 11 and 13,
respectively.
JBB1, JBB2 - Joystick B Buttons, Input - Internal Pullups
These pins are the switch inputs for the second joystick, Joystick B. They should be connected
to joystick connector pins 10 and 14, respectively; as well as have a 1 nF capacitor to ground.
CS4610 DSP Serial Port Interface
The CS4610 DSP serial port pins are shared with the CS9236 Wavetable serial port. When the serial
port is enabled, SPE = 1 in I16, these pins are forced to the CS4610 DSP interface.
FSYNC - Frame Sync, Output
When the serial port is enabled, SPE = 1 in I16, this pin is the serial frame sync output.
SCLK - Serial Clock, Output (CDROM Enable)
When the serial port is enabled, SPE = 1 in I16, this pin is the serial clock output. At power-up,
this pin is an input (with an internal 100 kΩ pullup) that, when pulled low with a 10 kΩ
resistor to SGND, enables the CDROM interface (over the upper 4 ISA address pins). Loading
must be limited to CMOS inputs if this pin has the 10 kΩ resistor attached.
SDOUT - Serial Data Output, Output (Alternate CDROM Chip Select Enable)
When the serial port is enabled, SPE = 1 in I16, this pin is the serial data output. At power-up,
this pin is an input (with an internal 100 kΩ pullup) that, when pulled low with a 10 kΩ
resistor to SGND, enables the alternate CDROM chip select pin ACDCS. Loading must be
limited to CMOS inputs if this pin has the 10 kΩ resistor attached.
SDIN - Serial Data Input, Input
When the serial port is enabled, SPE = 1 in I16, this pin is the serial data input.
DS253PP2
87