Ampro Corporation XTX 820 Benutzerhandbuch

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Chapter 3 
Hardware
XTX 820
Reference Manual
31
AC'97/HDA CODEC
The additional signals provided by J2 support AC'97 digital audio CODECs as well HDA (High
Definition Audio) audio CODECs.
Table 3-12.  Audio CODEC Interface Pin/Signal Descriptions (J2)
Pin #
Signal
Description
81
AC_RST*
AC'97/HDA CODEC Reset
85
AC_SYNC
AC'97/HDA Serial Bus Synchronization
89
AC_BIT_CLK
AC'97/HDA 12.228 MHz Serial Bit Clock from CODEC
82
AC_SDOUT
AC'97/HDA Audio Serial Data Output to CODEC
86
AC_SDIN0
AC'97/HDA Audio Serial Data Input from CODEC0
87
AC_SDIN1
AC'97/HDA Audio Serial Data Input from CODEC1
88
AC_SDIN2
AC'97/HDA Audio Serial Data Input from CODEC2
79
CODECSET
AC`97/HDA Disable onboard Audio CODEC
Notes: The shaded area denotes power or ground.  The signals marked with * = Negative true logic.
LPC Interface
The LPC (Low Pin Count) bus is provided as a replacement for the increasingly less often used ISA bus.
The LPC bus is used on PC-style personal computers to connect low-bandwidth devices to the CPU,
such as the boot ROM, "legacy" I/O devices (supported by a Super I/O chip), and audio controllers.  The
"legacy" I/O devices usually include serial and parallel ports, keyboard, mouse, and a floppy disk
controller.  Due to the software compatibility of the LPC bus to the ISA bus, I/O devices such as
additional serial ports can be easily implemented on an application specific baseboard using the LPC
bus.  There are also many devices available for the LPC bus.
Table 3-13.  LPC Interface Pin/Signal Descriptions (J2)
Pin #
Signal
Description
91
LPC_AD0
LPC Multiplexed Command, Address and Data Line 0
93
LPC_AD1
LPC Multiplexed Command, Address and Data Line 1
94
LPC_FRAME*
LPC Frame – Indicates start of a new or termination of a broken cycle.
95
LPC_AD2
LPC Multiplexed Command, Address and Data Line 2
96
LPC_DRQ0*
LPC Encoded DMA/Bus Master Request Line 0
97
LPC_AD3
LPC Multiplexed Command, Address and Data Line 3
98
LPC_DRQ1*
LPC Encoded DMA/Bus Master Request Line 1
Notes: The shaded area denotes power or ground.  The signals marked with * = Negative true logic.
Extended System Management
The Extended System Management interface, implemented by the Super I/O chip (W83627HG), provide
additional signals and functions to further improve system management.  One of these signals is an
output signal called FAN_PMOUT that allows system fan control using a PWM (Pulse Width
Modulation) Output.  Additionally there is an input signal called FAN_TACHOIN that provides the
ability to monitor the system fan's RPMs (revolutions per minute).