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Using Arduino => Programming Questions => Topic started by: 0x776F6F74 on Jun 09, 2016, 08:45 pm

Title: mfrc522 power consumption
Post by: 0x776F6F74 on Jun 09, 2016, 08:45 pm
Anyone know how to power down mfrc522?.
thx
Title: Re: mfrc522 power consumption
Post by: spycatcher2k on Jun 09, 2016, 09:36 pm
Put a transistor on the ground line and use a digital pin the turn the unit On and Off.  :)
Title: Re: mfrc522 power consumption
Post by: 0x776F6F74 on Jun 09, 2016, 10:51 pm
Yeah but then I would some kind of sensor to fire up interrupt mini pro and init 4x3 keypad and rc522.
Also this sensor would need to have a low power consumption. Any ideas?
Title: Re: mfrc522 power consumption
Post by: spycatcher2k on Jun 09, 2016, 11:06 pm
Quote
mini pro and init 4x3 keypad and
Not in original question!!!  >:(
Title: Re: mfrc522 power consumption
Post by: 0x776F6F74 on Jun 10, 2016, 01:46 am
I guess I could have been a bit more specific Im coding a medium security access control system.
Idea was to swap out the pcb in this cheap chinense electonic safe with protype pcb + mini pro + rc522 + keypad powerd by 4xAA battery series 6V. Coding is almost done only power consumption left and interrupt.

project so far done
* eeprom wear level 1.1 millon eeprom write cycles (1 KB version assuming no cell failures) floating structure 5 rfid user 1 programming card config
* 2 anti clone tricks
* Write to free sector any card in transport config and default keys mifare classic
* Buzzer, led feedback on button press and matching password or random number rfid
* 3 times wrong password 8 sec delay
* progamming mode button press wipe eeprom except wear level counter and marker
* auto reset
Title: Re: mfrc522 power consumption
Post by: 0x776F6F74 on Jun 10, 2016, 11:31 pm
Set and clear powerdown bit
Code: [Select]
mfrc522.PCD_WriteRegister(0x02, 0x10);
mfrc522.PCD_WriteRegister(0x02, 0x00);


28mA reduction :)