W83791D Information Storage Devices, Inc, W83791D Datasheet - Page 8

• Manufacturer Part Number: W83791D
• Description: Hardware Monitor With Speech Synthesizer And Asf Functions
• Manufacturer: Information Storage Devices, Inc

1. GENERAL DESCRIPTION
IC. Besides the conventional functions of W83782D, W83791D uniquely provides several innovative features such
as speech function, ASF sensor compliant, SMBus 2.0 ARP command compatible, VID table selection trapping, and
5VID output control. Conventionally, W83791D can be used to monitor several critical hardware parameters of the
system, including power supply voltages, fan speeds, and temperatures, which are very important for a high-end
computer system to work stably and efficiently. As for data access, W83791D provides slave SMBus 2.0 interface
which can reply PEC (Packet Error Code) when as ASF sensor.
monitor 10 analog voltage inputs (including power VDD/5VSB monitoring), 5 fan tachometer inputs, 3 remote
temperatures, and one case open detection signal. The sense of remote temperature can be performed by thermistors,
2N3904 NPN-type transistors, or directly from Intel
(pulse width modulation) outputs for two modes of smart fan control-} Thermal Cruise
Cruise} mode. Under } Thermal Cruise
specific programmable ranges under the hardware control. }Speed Cruise}, namely, is to keep the fan operate in the
specific programmable r.p.m . As for warning mechanism, W83791D provides speech voice warning, beep tone
warning, and SMI#, OVT#, IRQ signals for system protection events.
VID inputs provide the information of Vcore voltage that CPU expects. Furthermore, W83791D provides
programmable VID output control to alter the voltage CPU consumes. W83791D also uniquely provides an optional
feature: early stage (before BIOS was loaded) beep / speech warning to detect if the fatal elements present --- Vcore
or +3.3V voltage fail and thus the system can not be boomed up. If the VSB power on setting refers to Intel VRM
9.x, the VID table within W83791D will be according to the new one. W83791D also has 2 specific pins to provide
selectable address setting for application of multiple devices (up to 4 devices) wired through I
DAC output as well as a connectable external flash memory for storing voice data. W83791D supports 1 CPU
present or absent event trap, 5 external event traps, 17 hardware monitor event traps (10 analog voltage, 3 fan
tachometer, 3 remote temperature, 1 case open) and 128 internal programmable event traps, amounting to 151
different speech outputs. If more than two events happen simultaneously, the priority set is: SLOTOCC# >
EVNTRP1 > EVNTRP2 > EVNTRP3 > EVNTRP4 > EVNTRP5 > 128 Programmable events (Bank0 index 09h) >
17 Hardware status events. Voice data stored in the external flash memory interface with Winbond W55FXX is
flexible to change by Winbond application software and on-line programming flash data is provided also. Besides,
An external resistor is added to provide ring oscillator.
designer through a set of General Purpose I/O ports. These GPIO ports may serve as simple I/O or may be
individually configured to provide a pre-defined alternate function. If pin 9 (SPEECH_SEL) is trapped to high at
VSB power on, this function will be active.
network management in OS-absent state. Through W83791D’s compliance with ASF sensor spec , network server is
able to monitor the environmental status of the client in OS-absent state by PET frame values returned from
W83791D, such as temperatures, voltages, fan speed, and case open. Moreover, W83791D supports SMBus 2.0
ARP command to solve the problem of address conflicts by dynamically assigning a new unique address to
W83791D after W83791D’s UDID is sent.
When you do not use the speech function, W83791D provides a set of flexible I/O control functions to the system
W83791D is an evolving version of the W83782D --- Winbond's most popular hardware status monitoring
An 8-bit analog-to-digital converter (ADC) was built inside W83791D. W83791D can simultaneously
Additionally, 5 VID inputs are provided to read the VID of CPU (i.e. Pentium
W83791D speech function is enabled by building in a programmable speech synthesizer with a 9-bit current
W83791D can uniquely serve as an ASF sensor to respond to ASF master’s req uest for the implementation of
Through the application software or BIOS, the users can read all the monitored parameters of the system
TM
~ mode, temperatures of CPU and the system can be maintained within
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CPU with thermal diode output. W83791D provides 3 PWM
1
Publication Release Date: Aug, 2001
TM
II/III) if applicable. These
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2
C
~ mode and }Speed
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W83791D
Preliminary
Revision 0.41
interface.