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Electronics => Microcontrollers => Topic started by: sangar on December 13, 2018, 08:52:31 am

Title: What is Data flash memory not Flash memory, in Microcontroller?
Post by: sangar on December 13, 2018, 08:52:31 am
Hello all,

I have just look at M487JIDAE nuvoton microcontroller which has Flash memory of 512KB and SRAM-160KB...Other than this, it has Data Flash memory which is configurable...Could anyone tell the purpose of Data Flash memory?

Thanks,
Muthu
Title: Re: What is Data flash memory not Flash memory, in Microcontroller?
Post by: ataradov on December 13, 2018, 09:17:01 am
It is a section of the main flash array dedicated for storing data. It is writable even if the rest of the array is locked for writing.
Title: Re: What is Data flash memory not Flash memory, in Microcontroller?
Post by: sangar on December 13, 2018, 02:21:57 pm
Hi Alex,

Thanks...So, Can I take it as EEPROM?...


Regards,
Muthu
Title: Re: What is Data flash memory not Flash memory, in Microcontroller?
Post by: mikeselectricstuff on December 13, 2018, 02:42:44 pm
Quote from: ataradov on December 13, 2018, 09:17:01 am
It is a section of the main flash array dedicated for storing data. It is writable even if the rest of the array is locked for writing.
And probably has higher endurance
Title: Re: What is Data flash memory not Flash memory, in Microcontroller?
Post by: mikeselectricstuff on December 13, 2018, 02:44:15 pm
Quote from: sangar on December 13, 2018, 02:21:57 pm
Hi Alex,

Thanks...So, Can I take it as EEPROM?...


Regards,
Muthu
Yes, except it is probably only eraseable in large blocks - typically smaller than than program memory block size but if it's called flash and not eeprom it's unlikely to have single byte erase, so you need to do a read/erase/rewrite to update individual bytes
Title: Re: What is Data flash memory not Flash memory, in Microcontroller?
Post by: legacy on December 13, 2018, 02:50:40 pm
Why FeRam is still so expensive? it would be nice to have it instead of Flash.
Title: Re: What is Data flash memory not Flash memory, in Microcontroller?
Post by: David Hess on December 13, 2018, 02:57:17 pm
Quote from: legacy on December 13, 2018, 02:50:40 pm
Why FeRam is still so expensive? it would be nice to have it instead of Flash.

It requires extra processing steps which are not native to a CMOS process.  Flash just requires floating gates.
Title: Re: What is Data flash memory not Flash memory, in Microcontroller?
Post by: tszaboo on December 13, 2018, 02:59:27 pm
Quote from: legacy on December 13, 2018, 02:50:40 pm
Why FeRam is still so expensive? it would be nice to have it instead of Flash.
We really should have MRAM microcontrollers with unified memory space, replacing the 3-4 different memory types on these kind of projects. Because large MRAM can replace Flash, EEPROM, NVRAM and SRAM. Only if Everspin wouldn't concentrate on the wrong market.
Title: Re: What is Data flash memory not Flash memory, in Microcontroller?
Post by: ataradov on December 13, 2018, 03:35:48 pm
Quote from: mikeselectricstuff on December 13, 2018, 02:42:44 pm
And probably has higher endurance
No, it it is quite literally logically reserved part of the main flash array. It is no different than main memory. The only thing that is different about it is logic that defines write permissions.
Title: Re: What is Data flash memory not Flash memory, in Microcontroller?
Post by: ataradov on December 13, 2018, 03:37:47 pm
Quote from: sangar on December 13, 2018, 02:21:57 pm
Thanks...So, Can I take it as EEPROM?...
It has 4K erase granularity. In order to make it really work as EEPROM, you would have to create some emulation layer.
Title: Re: What is Data flash memory not Flash memory, in Microcontroller?
Post by: sangar on December 13, 2018, 04:46:07 pm
Thank you very much to make me understand this...


Thanks,
Muthu