AUTOSAR from introduction to mastery 100 lectures (50) - AUTOSAR memory management series - ECU abstraction layer and MCAL layer

1 MemStack ECU Abstraction layer and MCAL Layer Introduction

In this paper , The topic of discussion is with AUTOSAR Memory service in (MemStack) dependent ECU Abstraction layer and MCAL layer .

For memory services ECU The abstraction layer consists of memory interfaces (MemIf)、 Flash memory EEPROM Simulation (FEE) and EA(EEPROM abstract )、 External flash drivers and external devices EEPROM Driver and other modules .

MCAL The layer consists of internal flash driver and internal EEPROM Driver components .

Memory interface （MemIf） From the lower level Flash and EEPROM Abstract in the module , And provide a unified address space for the upper layer .

2 simulation EEPROM

• Flash EEPROM Emulation The concept of

EEPROM And flash memory are nonvolatile memory , It consists of a set of storage units , Each unit holds one or more bits of information .

You can pair... On byte or word boundaries EEPROM Programming and erasing , This can be done on a single unit , Without interfering with other values .

Flash memory can be programmed on word or double word boundaries , Larger sizes can also be used , But erasure can only be performed on the sector boundary , The sector size is mainly in Kilobytes In units of .Flash The data in is in pages （ Minimum number of bytes that must be written at one time ） Write... In units , And sector （ Minimum number of bytes that must be erased at one time ） Erase in units .

Flash memory can be used to store data , These data usually use Flash EEPROM Emulation Stored in EEPROM in , The flash memory is based on Record File system .

In this file system Record Is a set of variables , By the state of the block （ Record + data ）、 Block identifier and data length .