On Sunday 10 August 2003 10:52, Ranganadh wrote:
Next GLUG Meet on 10th Aug. @ Ruparel College, Matunga Rd. (W), @
4.00pm
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D'souza,
thanks for your reply........and also special thanks to ur language.....
Err.. what is that ?
But I had one fundamental doubt regarding last point.....
jffs2 file systems uses wear levelling and bad sector marking to
99 percent industrial applications has life cycle more than 2 years... I am not designing toys...
In which case using X86 based designs is not a very good idea.
so u r saying that ...... life cycle is only 2 years...
By couple of yrs I mean 5 ~ 7 yrs. It depends on number of writes to the flash. A rough example if u r using a 20Ksps 12 bit ADC your data rate is 40KB/s. with a maximum erase write cycle of 1000000 and wear levelling, device life will be 4.75 years. If u use JFFS2 which has built in compress/decompress life will be higher. On the other hand u will have many more ADCs and sensors, hence higher write loads so reduced life..... etc. etc.
two years what ever you r saying is very less.... suppose if am using flash disk in my industrial control system... I need to change it every two years...
That is nonetheless better than harddisks in an industrial environment.
Because of your design (according to u it is good ),,,
A design is only as good as the underlying assumptions made about it's environment and use.
suppose I am using around 50 industrial controllers at my work place..... I need to replace 50 flash disk every 2 years......
More like 4~6yrs - quite manageable. The real problem is in unmanned remote installations.
rgds jtdsouza@softhome.net