MEC1404 Datasheet, PDF (456/572 Pages) Microchip Technology – Keyboard and Embedded Controller Products for Notebook PC

MEC140X/1X
37.9.1 VCI REGISTER
Offset ^00h
Bits
DESCRIPTION
31:13 Reserved
12 FILTERS_BYPASS
The Filters Bypass bit is used to enable and disable the
input filters on the VCI_IN# pins. See Section 43.24,
"VBAT-Powered Control Interface Timing," on page 533.
1=Filters disabled
0=Filters enabled (default)
11 FW_EXT
This bit controls selecting between the external VBAT-
Powered Control Interface inputs, or the VCI_FW_CN-
TRL bit output to control the VCI_OUT pin.
1=VCI_OUT is determined by the VCI_FW_CNTRL field,
when VTR is active
0=VCI_OUT is determined by the external inputs.
10 VCI_FW_CNTRL
This bit can allow EC firmware to control the state of the
VCI_OUT pin. For example, when VTRGD is asserted
and the FW_EXT bit is ‘1’, clearing the VCI_FW_CNTRL
bit de-asserts the active high VCI_OUT pin.
BIOS must set this bit to ‘1’ prior to setting the FW_EXT
bit to ‘1’ on power up, in order to avoid glitches on the
VCI_OUT pin.
9 VCI_OUT
This bit provides the current status of the VCI_OUT pin.
8 VCI_OVRD_IN
This bit provides the current status of the VCI_OVRD_IN
pin.
7:2 Reserved
1:0 VCI_IN#
These bits provide the latched state of the associated
VCI_IN# pin, if latching is enabled or the current state of
the pin if latching is not enabled. In both cases, the value
is determined after the action of the VCI Polarity Register.
TYPE
R
R/W
R/W
R/W
R
R
R
R
DEFAULT
-
0
RESET
EVENT
-
VBAT_POR
0
nSYSRST
&
VBAT_POR
0
See
–
Note 1
See
Note 1
-
-
See
Note 1
Note 1: The VCI_IN[1:0]# and VCI_OVRD_IN bits default to the state of their respective input pins. The VCI_OUT
bit is determined by the VCI hardware circuit
DS00001956D-page 456
 2015 - 2016 Microchip Technology Inc.