S29GL01GS datasheet(25/104 Pages) SPANSION

25 / 104 page

March 16, 2012 S29GL_128S_01GS_00_06

GL-S MirrorBit® Family

Data

She e t

Embedded Operations

5.1

Embedded Algorithm Controller (EAC)

The EAC takes commands from the host system for programming and erasing the flash memory array and

performs all the complex operations needed to change the non-volatile memory state. This frees the host

system from any need to manage the program and erase processes.

There are four EAC operation categories:

 Standby (Read Mode)

 Address Space Switching

 Embedded Algorithms (EA)

 Advanced Sector Protection (ASP) Management

5.1.1

EAC Standby

In the standby mode current consumption is greatly reduced. The EAC enters its standby mode when no

command is being processed and no Embedded Algorithm is in progress. If the device is deselected

(CE# = High) during an Embedded Algorithm, the device still draws active current until the operation is

completed (ICC3). ICC4 in DC Characteristics on page 74 represents the standby current specification when

both the Host Interface and EAC are in their Standby state.

5.1.2

Address Space Switching

Writing specific address and data sequences (command sequences) switch the memory device address

space from the main flash array to one of the Address Space Overlays (ASO).

Embedded Algorithms operate on the information visible in the currently active (entered) ASO. The system

continues to have access to the ASO until the system issues an ASO Exit command, performs a Hardware

RESET, or until power is removed from the device. An ASO Exit Command switches from an ASO back to the

main flash array address space. The commands accepted when a particular ASO is entered are listed

between the ASO enter and exit commands in the command definitions table. See Command Summary

on page 57 for address and data requirements for all command sequences.

5.1.3

Embedded Algorithms (EA)

Changing the non-volatile data in the memory array requires a complex sequence of operations that are

called Embedded Algorithms (EA). The algorithms are managed entirely by the device internal Embedded

Algorithm Controller (EAC). The main algorithms perform programming and erase of the main array data and

the ASO’s. The host system writes command codes to the flash device address space. The EAC receives the

commands, performs all the necessary steps to complete the command, and provides status information

during the progress of an EA.

S29GL01GS датащи(PDF) 25 Page - SPANSION