47N227 Datasheet, PDF (113/202 Pages) SMSC Corporation – 100 Pin Super I/O with LPC Interface for Notebook Applications

nPCI_RESET
PCI_CLK
SER_IRQ
Unchanged
Unchanged
Unchanged
FDD Interface Pins
All pins in the FDD interface which can be connected directly to the floppy disk drive itself are either
DISABLED or TRISTATED.
Pins used for local logic control or part programming are unaffected. Table 46 depicts the state of the
floppy disk drive interface pins in the powerdown state.
Table 46 - State of Floppy Disk Drive Interface Pins in Powerdown
FDD PINS
STATE IN AUTO POWERDOWN
INPUT PINS
nRDATA
Input
nWRTPRT
Input
nTRK0
Input
nINDEX
Input
nDSKCHG
Input
OUTPUT PINS
nMTR0
Tristated
nDS0
Tristated
nDIR
Active
nSTEP
Active
nWDATA
Tristated
nWGATE
Tristated
nHDSEL
Active
DRVDEN[0:1]
Active
UART Power Management
Direct power management is controlled by CR02. Refer to the Configuration section for more information.
Auto Power Management is enabled by the UART1 and UART2 enable bits in CR07. When set, these bits
allow the following auto power management operations:
1. The transmitter enters auto powerdown when the transmit buffer and shift register are empty.
2. The receiver enters powerdown when the following conditions are all met:
A.
B.
Note:
Receive FIFO is empty
The receiver is waiting for a start bit.
While in powerdown the Ring Indicator interrupt is still valid and transitions when the RI input
changes.
Exit Auto Powerdown
The transmitter exits powerdown on a write to the XMIT buffer. The receiver exits auto powerdown when
RXDx changes state.
Parallel Port
113