Please Help,

Hi, Im using arduino uno and I only know the basics of it. I need some help with my project, i am making a bond paper vending machine with LCD, it displays the number of available bond paper (example, available: long = 100 & short=100) and when a bondpaper is consumed ,the available bondpaper will decrease depending on the number of paper consumed (example, when 3 long bondpaper was consumed then it will display available : Long = 97 & short = 100). but when the project is turned off and turned on again, the display resets, the available bondpaper is back to : long = 100 & short = 100. what should i do so that it will not be reset? so that it will continue the last record. what should i use? im sorry for the grammar . thank you XD

You could write the amounts to EEPROM each time that a paper is removed. Then in setup() read the EEPROM to get the previous totals.

thank you so much .. :)

I should mention that EEPROM "wears out". You can expect to write to particular locations about 10,000 times before those locations become unusable. To get around this a technique called "wear leveling" is used where you move to a new location when you write so as to not use the same locations over and over. If you write to EEPROM infrequently this may not be relevant.


Write/Erase Cycles: 10,000 Flash/100,000 EEPROM

Thanks, Crossroads. My mistake.