89c51

[ash20]

Hi all

I have to make my major project on attendance recording system and i am using Atmel's "89c51".
the only problem is saving data .. i have to save 5 teachers data (for 5 period) for one full month . now problem is that i have to save the data for present class, close the system, restart it for next period and so on for all 5 periods because i cannot keep the system (the attendance system) on for 5 periods as it will be considerable waste of electricity. and if i dnt do this, all my data will be lost from ram. also i cant save the data every time on pc as this is not allowed. save whole day data is the requirement.

so in short, i have thought of saving data in pen drive. and for this, i need the circuitary and ic's used to connect the pendrive to 89c51.. so plzzzz help me...

 

[mvs sarma]

the philosophy of using pendrive for microcontroller, if not 89c52, is just published in elektor.com December 2011 issue. you can join membership there and down load the article. Here is the link
**broken link removed**
All the best....

 

[ash20]

should i download the article?? it has the circuit diagram ?

 

[mvs sarma]

obviously, Yes
if i supply you the copy of that, it becomes illegitimate. it is cheap enough. It has a schematic using PIC24Fxxx.

Incidentally, you might find a cheaper alternative in using SD card interface to micro and many placers you get the such designs by googleing.

 

[ash20]

actually i was worried to use those 10 points so i was verifying. now another prob is tht i want ckt for 89c51. it is given for pic one.. now what?

 

[mvs sarma]

once you study the concept of using usb drive,
you can perhaps apply it on other micros. BUT, you have to, in case of 89C5x ( in fact better use 89S5x) you have to write or get a software based (host mode) USB pen drive protocol. Instead, SD card interface might be simpler as there are enough examples in the Google.

 

[ash20]

ok thanks. if i get any problem, i will ask again.