hello everyone

today let's learn about LPC bus or ESPI bus

first let's talk about LPC bus

LPC bus it is low pin count bus

in notebook martyr board

it is used for communication between PCH and EC

usually consists of the following signals

for example

the power supply VCC of the LPC bus module of TC

it is powered by 3.3 votes after booting

next are L a d 0 to L a d 3

these

4 lines belong to the Dress Data recumbination line

all data and address information between EC and PC H

are transmitted through these

4 address data recombination lines

then next this LPCCLK

this is the LPC bus clock

its clock frequency is usually 33 herds or 24 herds

next here is Lframe Pouncin

which is the LPC bus frame cycle signal

it is active low

when this signal is valid

indicates the start or end of a data transfer

on the LPC bus

next this LPC rst pound sign

is the reset signal of the LPC bus

these are the LPC bus conditions

during the maintenance process

we usually judge whether the communication between EC

and the PCH is normal

by measuring the LPC bus waveform

next let's talk about ESPI bus

it was proposed by Intel in 2017 to replace LPC bus

it copies the pain definations of SPI 4 time speed

regarding the SPI 4 time speed pin definition

we have introduced it in the courts of

SPI bus introduction

at the same time

this alert and reset pins have been added

for example CLK

this is the ESPI bus clock

I O there are 4 lines of I O 0 to I O 3 in total

this is the data in

data out bus used to transmit data on ESPI bus

CS pound sign

chip select signal

the function of this

chip select is the same as the frame period of the

LPC bus alert pound sign

this function is similar to the paws

interrupt the signal of the SPI bus

reset pants sign

this is the reset of the ESPI bus

the function of this pin is similar

to the reset signal of the LPC bus

then the power supply

the power supply of the EC's ESPI module is 1.8 votes

this is the ESPI bus