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be used to specify when the relevant data is on the other Flash bank. The following table is

showing an example of status bits that can be used for this purpose.

To improve the detection in case of partially erased bank and as explained in Chapter 2, it is

proposed to insert a small number of fixed data inside the Data-sets so that by running check-

sum it is possible to detect if a given Flash bank has valid or invalid data.

Then, the EEPROM emulation software should analyse the content of the Flash banks detect-

ed to contain valid data, in order to check the consistency of the status bits. This algorithm is

application dependent as the possible combinations depend on the selected implementation

and the different events that the application has to withstand due to the design features (ex:

power-fail).

Table 3. Status bit for Flash banks

Status bit value

Meaning

01111111

current bank is active

00111111

erase of the other bank is started

00011111

completion of the erase of the other bank

00001111

new data programming in the other bank is started

00000111

new data programming in the other bank is completed

00000011

the other bank is active