cs4239 Cirrus Logic, Inc., cs4239 Datasheet - Page 56

• Manufacturer Part Number: cs4239
• Description: Crystalclear? Ortable Isa Audio System Logic
• Manufacturer: Cirrus Logic, Inc.

Input Control Register,
Mixer Index 0CH
This register selects the input source to the ADC.
Output Control Register,
Mixer Index 0EH
Master Volume Register,
Mixer Index 22H, Default = 99H
This register provides 8 steps of master volume
control each for the right and left channels.
FM Volume Register,
Mixer Index 26H, Default = 99H
This register provides 8 steps of FM volume
control each for the right and left channels.
CD Volume Register,
Mixer Index 28H, Default = 01H
This register provides 8 steps of CD volume
control each for the right and left channels.
Line-In Volume Register,
Mixer Index 2EH, Default = 01H
This register provides 8 steps of line-in volume
control each for the right and left channels.
GAME PORT INTERFACE
The Game Port logical device software interface
utilizes 10-bit address decoding and is located at
PnP address ’GAMEbase’. 10-bit addressing re-
quires that the upper address bits be 0 to decode
a valid address, i.e. no aliasing occurs. For back-
wards compatibility, the Game Port consists of
8 I/O locations which alias to the same location,
consisting of one read and one write register.
56
D2,D1 -
VSTC -
00 - Microphone
01 - CD Audio
10 - Microphone
11 - Line In
0 - Mono Mode
1 - Stereo Mode
Plug and Play configuration capability will allow
the joystick I/O base address, GAMEbase, to be
located anywhere within the host I/O address
space. Currently most games software assume
that the joystick I/O port is located at 200h.
A write to the GAMEbase register triggers four
timers. A read from the same register returns
four status bits corresponding to the joystick fire
buttons and four bits that correspond to the out-
put from the four timers.
A button value of 0 indicates the button is
pressed or active. The button default state is 1.
When GAMEbase is written, the X/Y timer bits
go high. Once GAMEbase is written, each timer
output remains high for a period of time deter-
mined by the current joystick position. The
number in parenthesis below is the joystick con-
nector pin number.
GAMEbase+0 - GAMEbase+7
JACX
JACY
JBCX
JBCY
JAB1
JAB2
JBB1
JBB2
JBB2
D7
JBB1
D6
CrystalClear Portable ISA Audio System
JAB2
D5
Joystick A, Coordinate X (pin 3)
Joystick A, Coordinate Y (pin 6)
Joystick B, Coordinate X (pin 11)
Joystick B, Coordinate Y (pin 13)
Joystick A, Button 1 (pin 2)
Joystick A, Button 2 (pin 7)
Joystick B, Button 1 (pin 10)
Joystick B, Button 2 (pin 14)
JAB1
D4
TM
JBCY
D3
JBCX
D2
JACY
D1
CS4239
DS253PP2
JACX
D0