Picdude wrote:

>On Tuesday 24 February 2004 05:57 am, David Duffy scribbled:
>
>
>>Here's some working EE code on a '628.
>>
>>      ...
>>
>>
>>I do the first write, then exit back to the main loop right away
>>to deal with other tasks. Checking the eeprom busy state at
>>the start of the eeprom write is a more efficient way to do it.
>>Clearing the write enable during writing *may* be causing
>>your problem. I wait until the write is finished and that works.
>>David...
>>
>>
>
>Interesting way to do it.  In my case, I would just wait in a busy-loop until
>that flag is set, and then continue with the rest of the code.  This is cause
>the main routine really does not *need* to do anything else during this time.
>
>I can see an easy way to set a timeout with this ... ie: while waiting until
>the flag is set, I could/should add a "timeout" counter which would assume
>that something went wrong if the flag was not set in a certain amount of
>time.  What's a reasonable amount of time for this?  Hopefully it's less than
>the time between EEPROM writes in my app.  I've calculated that my app can
>write a new value to EEPROM as fast as every 0.29 secs.  [ Hmmm ... that
>seems pretty short now that I think about it, but it's the very *worst* case.
>

My application has to monitor a RF remote receiver, a push button, flash
an led and do serial comms in between the eeprom writing and reading
so the wait-while-previous-byte-writing was the best way to go for me.
I think the eeprom byte write time on a 'F628 is in the order of 8-10ms.
David...

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___________________________________________
David Duffy        Audio Visual Devices P/L
U8, 9-11 Trade St, Cleveland 4163 Australia
Ph: +61 7 38210362   Fax: +61 7 38210281
New Web: www.audiovisualdevices.com.au
___________________________________________

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