Black cat takes you to learn EMMC Protocol Part 10: EMMC read and write operation details (read & write)

This paper is based on eMMC JEDEC5.1 And personal work experience , If there is any mistake, please leave a message .
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1 summary

1.1 What is a read-write operation

about emmc Come on , The most important operation , Just read and write . After all emmc It's a memory chip , Specifically used to access data , And storing data is right emmc Read and write .

for example , Save a photo emmc, This process is host Transfer data to emmc In the device , It is called a write operation . Empathy , Remove this photo from emmc out , The process is emmc Transfer data to host, Called read operation .

1.2 data bus

emmc There is 8 Data line , There are three bus options for data transmission ：
1 Line （DATA0）,4 Line （DATA0_{DATA3）,8 Line （DATA0}DATA7）

For each data line , Each clock cycle can transmit 1bit(single data rate) and 2bits（dual data rate） data .

1.3 Reading and writing classification