RM48L952: Block size Problem of FEE Virtual Sector

영호 안 said:

Will there be any problems using FEE with the above settings?

The Configuration of Virtual sector (VS) is not correct. VS1 (sector 0~sector 3) and VS2 (sector 3) has overlap, and VS1 and VS2 don't have the same size.

영호 안 said:

Virtual Sector1 and 2 are each 32Kbytes for a total of 64Kbytes, but I don't know why the block size cannot be set above 32Kbytes.

Please see the FAQ: https://e2e.ti.com/support/microcontrollers/arm-based-microcontrollers-group/arm-based-microcontrollers/f/arm-based-microcontrollers-forum/1121634/faq-tms570lc4357-questions-regarding-fee-eeprom-usage-on-hercules-microcontrollers/4158257?tisearch=e2e-sitesearch&keymatch=FEE%2520AND%2520block%2520size#4158257

The emulated EEPROM is divided into two or more Virtual Sectors. Each Virtual Sector is partitioned into several Data Blocks. A Virtual Sector can contain one or more contiguous physical flash sectors. A minimum of 2 Virtual Sectors are required to support the TI FEE Driver.

The size of a virtual sector MUST be larger than the size of all the Data Blocks. 

When programming data to EEPROM, the data is written to the first empty location in the Active Virtual Sector. If there is insufficient space in the current Virtual Sector to update the data, it switches over to the next Virtual Sector and copies all the valid data from the other Data Blocks in the current Virtual Sector to the new one. After copying all the valid data, the current Virtual Sector is marked as ready for erase and the new one is marked as Active Virtual Sector. Any new data is now written into the new Active Virtual Sector and the Virtual Sector which is marked as ready for erase will be erased in background. 

Data Bock Size = payload size + 24 bytes (header size)

The maximum size for data block in one VS is: VS size - 32 bytes (VS header) = 32KB - 32 bytes in your case

What I want to ask is the block size setting in VS2.
I set 32Kbyte for VS1 and 32Kbyte for VS2, but the block size I can set in HALCoGen is (32Kbyte - overhead).
Even when writing code in CCS, there is no Number of VS setting in the TI_Fee_WriteSync() function.
I want to set the block size to 64Kbyte. However, if the block size is larger than the size of VS, writing to FEE is not possible. How can I set the block size of VS2 and write?

Hello, I am using RM48L952.
According to the above, is 32Kbye the maximum data size that the RM48L952 can write at FEE?
If you count the overhead byte here, it will be less than 32 Kbytes, but what I'm curious about is that the RM48L952 has 64 Kbytes of FEE storage space. Why does the driver provided by TI set the VS operation as above and only use up to 32 Kbytes?

영호 안 said:

is 32Kbye the maximum data size that the RM48L952 can write at FEE?

No. The total block size should not be > VS size - header.

How many blocks do you have? 

There are 16 blocks. But the important thing is that although the FEE of the RM48L952 is 64 Kbytes, I understood that only 32 Kbytes of FEE can be used to use the TI Driver. Is my understanding right now?
Is there any way to use all 64 Kbytes of FEE?

I would like to ask you one last question.
QJ Wang sade: You can use 64KB, or 32KB in your application.
However, what I'm talking about is asking for the size that can be written at one time. As a result of my testing, the maximum size was 32712 bytes when writing at once with 2 virtual sectors and 1 block.
I had a question In order to use the driver provided by TI, two or more Virtual Sectors must be used. In this way, the maximum size that can be written at once is 32Kbye.
However, QJ Wang says that 64Kbytes are still available. I would like to know the exact information. In fact, the FEE is no different from 32Kbyte when using two Virtual Sectors.

Please be aware of the difference among FEE size, VS size, and block size, and their relations.

64KB is maximum FEE size = 2 * VS (32KB each) 

The maximum block size = VS size - VS header = 32KB - 32Bytes  = 32736 bytes

The payload length of the data block = block size - block header = 32736 bytes - 24 bytes = 32712 bytes.

The Bank 7 has 4 physical sectors.

You can also configure VS0=sector0 (16KB), and VS1=sector1 (16KB) --> FEE size = 32KB, and sector 2 and sector 3 are not used.

You can design two FEEs. VS0 (sector 0), and VS1 (sector1) --> FEE1

                                           VS0 (sector2), and VS1 (sector 3) --> FEE2

Then, is the maximum size that can be written to FEE at once 32712 bytes?
Is there any way to write more than 32712 kbytes at once?
This is because the amount of data that can be written at one time is too small even though FEE has a capacity of 64Kbytes.

Thanks for answering my question. Have a nice day.