Flash Sector Size on the QE128/96/64 family ?

[pbouf]

The QE128 Reference Manual states that the size of a sector for the Flash Sector Erase command is 1kBytes.

"The sector erase operation will erase all addresses in a 1 Kbyte sector of flash memory using an embedded
algorithm."

However, I am not sure if this applies to the QE64. I just discovered that only 512 bytes are erased for one single operation.

Can anyone confirm the flash sector size for each device in the QE128/96/64 family ?

[bigmac]

Hello,

According to the reference manual (paragraph 4.6.1) the sector size is 512 bytes for all devices.  This is consistent with other HCS08 devices and your tests (with only one exception that I know of having 768 byte sectors).  Whereabouts did you observe the quoted paragraph?  This could possibly be an error in the document.

Regards,

Mac

[pbouf]

Paragraph 4.6.1 talks about "pages" not sectors. "MC9S08QE64: 65,536 bytes (128 pages of 512 bytes each)".

Paragraph 4.6.3.2.4 states "The sector erase operation will erase all addresses in a 1 Kbyte sector of flash memory using an embedded algorithm.".

Page and sector don't usually have the same definition but I guess they do in the reference manual which I think is misleading.

[tonyp]

I think there is a mistake in the manual.  I've been using QE128 long enough to know flash pages are certainly 512-byte long.

I suspect by "sector" they are referring to the minimum amount of Flash that can be incrementally protected (FPROT register), which is 1K for the QE128/96/64, indeed.  And, I don't see a sector erase operation, only a page erase.  So, certainly a 'manual' bug.

[pbouf]

Paragraph 4.6.3.2, Table 4.23, there is a sector erase command 0x40. I don't see any page erase command.

Thank you for confirming the size of the sector/page is 512 bytes.

[tonyp]

It's becoming apparent that the word "sector" is used instead of "page" in all sections but two (4.6.1 and Table 4-22) of the QE128 manual.

With some "disassembly" then: Both descriptions refer to the same FCMD[6:0] value ($40) which is the command for erasing a single page, which is clearly defined in all documents to be a 512-byte block.

Therefore, a 1KB "sector" or "page" size reference is dead wrong.

P.S. I think I got it.  Due to the MMU capability of QE128/96/64 the word "page" is used a lot in reference to the 16KB PPAGE-controlled memory area.  So, they probably thought using "sector" for a flash page would lessen the confusion.  Well, DID IT?

[peg]

Hello,

Similar threads have occurred in the past like this, not to QE specifically but in general.

This thread just seems to confirm the outcome of the others. That is that Freescale are confused about the definition of these words as they apply to the memory within their microcontrollers. "Array" was another.

It seems to me that Freescale have no "official" definition and it is left to individual authors to use their own.

[J2MEJediMaster]

FWIW, I have reported this problem to the docs people.

---Tom

[bigmac · Accepted solution]

Hello,

It seems that both "page" and "sector" are variously used in the reference manual, and will generally mean the same thing.  Obviously, paragraph 4.6.3.2.4 contains an error, where the sector size stated contradicts other data from the same document.

Regards,

Mac