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Altera_Forum's avatar
Altera_Forum
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17 years ago

MaxII UFM

Hi everybody

I'm new on the forum and altera's cpld usage.

On my homebrew board epm1270 based, i need to save few bytes and recover them

to a single board p.c. via pc104 bus.

I'm not sure i can use ufm this way.

Can some one help me?

Consider that my english is as poor as my cpld knowhow.

thanks

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Most simple eeprom usage is with the par_eeprom Megafunction, see the component definition for reference: 

    COMPONENT par_eeprom IS
	PORT
	(
		addr	: IN STD_LOGIC_VECTOR (8 DOWNTO 0);
		di	: IN STD_LOGIC_VECTOR (15 DOWNTO 0);
		nerase	: IN STD_LOGIC ;
		nread	: IN STD_LOGIC ;
		nwrite	: IN STD_LOGIC ;
		data_valid	: OUT STD_LOGIC ;
		do	: OUT STD_LOGIC_VECTOR (15 DOWNTO 0);
		nbusy	: OUT STD_LOGIC 
	);
END COMPONENT;

    It's a simple asynchronous parallel memory with handshake signals.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    17 years ago

    Thanks a lot for suggestion.

    Actual fact, i have to store some bytes on 10" basis (roughly)

    and recover them just at boot time.

    I w'nt spend extra money for a zeropower device but on the other hand

    my doubt concern about flash's improper use(long term life)

    and whether it's necessary pass througt the sector erase each time data change

    from '0' to '1'.

    Any way really appreciate your help

    Alf
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    17 years ago

    By specification, MAX II has only 100 Erase and reprogram cycles. In V3.0 device handbook, they are listed as maximum instead of minimum, so you may ask, if Minimum is hopefully larger than 1? This may be a typo, but apparently, the flash isn't suited for periodical storage of data. I used it for calibration data, that may be rewritten a few 10 times during instrument lifetime.

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    17 years ago

    Definitly i'll be forced to implement more hardware:(

    thank a lot

    Alf
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    17 years ago

    Hi,

    does anybody knows, if there is a solution to implement a non-volatile counter using am MAXII and the UFM?

    Application is an "operation hour counter". I havent read the appnotes and the manual in detail yet...

    Thanks for help.

    Volker