MEC1404 Datasheet, PDF (153/572 Pages) Microchip Technology – Keyboard and Embedded Controller Products for Notebook PC

MEC140X/1X
Note:
Each logical device has a bank of Configuration registers that are accessible at offsets 30h to FFh via the
Configuration Port. The Logical Device number programmed in offset 07h determines which bank of con-
figuration registers is currently accessible.
7.3.1 HOST INTERFACE
The registers defined for the Chip Configuration are accessible by the Configuration Port when the device is in CONFIG
MODE. For a description of the Configuration Port and CONFIG MODE see the description of the LPC Interface.
7.4 Power, Clocks and Reset
This section defines the Power, Clock, and Reset input parameters to this block.
7.4.1 POWER DOMAINS
VTR
Name
Description
The logic and registers implemented in this block reside on this single
power well.
7.4.2 CLOCK INPUTS
This block does not require any special clock inputs.
7.4.3 RESETS
Name
Description
nSYSRST
Power on Reset to the block. This signal resets all the register and logic
in this block to its default state.
7.5 Interrupts
This block does not generate any interrupts.
7.6 Low Power Modes
This block always automatically adjusts to operate in the lowest power mode.
7.7 Description
The Chip Configuration Registers are divided into two groups: Global Configuration Registers and Logical Device Con-
figuration registers. The following descriptions assume that the LPC interface has already been configured to operate
in CONFIG MODE.
• Global Configuration Registers are always accessible via the LPC Configuration Port.
• The Logical Device Configuration registers are only accessible via the LPC Configuration Port when the corre-
sponding Logical Device Number is loaded in the Logical Device Number register. The Logical Device Number
register is a Global Configuration Register.
There are 48 8-bit Global Configuration Registers (at offsets 00h through 2Fh), plus up to 208 8-bit registers associated
with each Logical Device. The Logical Device is selected with the Logical Device Number Register (Global Configuration
Register 07h).
Sequence to Access Logical Device Configuration Register:
a) Write the number of the Logical Device being accessed in the Logical Device Number Configuration Register by
writing 07h into the INDEX PORT and the Logical Device Number into the DATA PORT.
b) Write the address of the desired logical device configuration register to the INDEX PORT and then write or read
the value of the configuration register through the DATA PORT.
 2015 - 2016 Microchip Technology Inc.
DS00001956D-page 153