[sdiy] DSI,storage of sound programs, setups, etc, dsPIC?

[Tom Wiltshire]

On 23 Mar 2011, at 22:30, Gordon JC Pearce wrote:

> On Wed, 2011-03-23 at 22:12 +0000, Tom Wiltshire wrote:
>> The question was "Why store programs to internal flash?" and "Cos it
>> saves using an external EEPROM" is the only answer I can really see,
>> to be honest. Otherwise, you'd just store whatever settings in EEPROM,
>> wouldn't you? But if you have flash on-chip, you might think "Aha! I
>> don't need EEPROM! I can use the internal flash!". I can't see any
>> other motivation for doing it. EEPROM probably has better
>> characteristics (retention/write/erase cycles etc). If that's not
>> true, then maybe robustness is another reason, but it seems unlikely.
> 
> Why wouldn't you save in the internal flash?  "Wearing out the flash"
> isn't really an answer, since you're unlikely to save patches a hundred
> million times in the life of the instrument.
> 
> Gordon MM0YEQ

It might not be that long. The dsPIC I've done this (save to the internal flash) on recently specifies 10,00 erase/write cycles minimum. The client for the job was happy with this. Some people may not consider that enough. Other dsPICs (some of the earlier ones?)  only specified 1000 times - enough for rarely changing config or calibration data, but probably no good for preset storage.

As always, "Read the datasheet" is probably good advice before making any decision either way. It's just a pity they don't make 'em more readable to encourage people to do just that!

T.