A000047 Arduino, A000047 Datasheet - Page 26
A000047
Manufacturer Part Number
A000047
Description
MCU, MPU & DSP Development Tools Mega2560
Manufacturer
Arduino
Series
-r
Type
MCUr
Specifications of A000047
Processor To Be Evaluated
ATmega2560
Interface Type
USB, I2C, SPI
Dimensions
4 in x 2.1 in
Operating Supply Voltage
5 V
Contents
Board
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
For Use With/related Products
ATmega2560
- Current page: 26 of 444
- Download datasheet (10Mb)
7.3.2
2549M–AVR–09/10
Preventing EEPROM Corruption
The next code examples show assembly and C functions for reading the EEPROM. The exam-
ples assume that interrupts are controlled so that no interrupts will occur during execution of
these functions.
Note:
During periods of low V
too low for the CPU and the EEPROM to operate properly. These issues are the same as for
board level systems using EEPROM, and the same design solutions should be applied.
An EEPROM data corruption can be caused by two situations when the voltage is too low. First,
a regular write sequence to the EEPROM requires a minimum voltage to operate correctly. Sec-
ondly, the CPU itself can execute instructions incorrectly, if the supply voltage is too low.
EEPROM data corruption can easily be avoided by following this design recommendation:
Keep the AVR RESET active (low) during periods of insufficient power supply voltage. This can
be done by enabling the internal Brown-out Detector (BOD). If the detection level of the internal
BOD does not match the needed detection level, an external low V
be used. If a reset occurs while a write operation is in progress, the write operation will be com-
pleted provided that the power supply voltage is sufficient.
Assembly Code Example
C Code Example
EEPROM_read:
unsigned char EEPROM_read(unsigned int uiAddress)
{
}
; Wait for completion of previous write
sbic EECR,EEPE
rjcmp EEPROM_read
; Set up address (r18:r17) in address register
out EEARH, r18
out EEARL, r17
; Start eeprom read by writing EERE
sbi EECR,EERE
; Read data from Data Register
in
ret
/* Wait for completion of previous write */
while(EECR & (1<<EEPE))
/* Set up address register */
EEAR = uiAddress;
/* Start eeprom read by writing EERE */
EECR |= (1<<EERE);
/* Return data from Data Register */
return EEDR;
1. See “About Code Examples” on page 11.
;
r16,EEDR
(1)
CC,
(1)
the EEPROM data can be corrupted because the supply voltage is
ATmega640/1280/1281/2560/2561
CC
reset Protection circuit can
26
Related parts for A000047
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Daughter Cards & OEM Boards ARDUINO UNO PROTO PCB REV 3
Manufacturer:
Arduino
Part Number:
Description:
Daughter Cards & OEM Boards ARDUINO SHIELD PROTO KIT REV 3
Manufacturer:
Arduino
Part Number:
Description:
Daughter Cards & OEM Boards ARDUINO MEGA PROTO KIT REV 3
Manufacturer:
Arduino
Part Number:
Description:
Daughter Cards & OEM Boards ARDUINO MEGA PROTO PCB REV 3
Manufacturer:
Arduino
Part Number:
Description:
Development Boards & Kits - AVR ARDUINO STARTER KIT W/ UNO REV3
Manufacturer:
Arduino
Part Number:
Description:
RF Development Tools ARDUINO SHIELD WIRELESS PROTO
Manufacturer:
Arduino
Datasheet:
Part Number:
Description:
RF Development Tools ARDUINO SHIELD WIRELESS WITH SD
Manufacturer:
Arduino
Datasheet:
Part Number:
Description:
Development Software Getting started w/Arduino
Manufacturer:
Arduino
Part Number:
Description:
Ethernet Modules & Development Tools Ethernet Shield for Arduino
Manufacturer:
Arduino
Part Number:
Description:
MCU, MPU & DSP Development Tools LilyPad Arduino Main Board
Manufacturer:
Arduino
Part Number:
Description:
ARDUINO NANO Board
Manufacturer:
Arduino
Datasheet:
Part Number:
Description:
Ethernet Modules & Development Tools ETHERNET SHEILD PoE FOR ARDUINO
Manufacturer:
Arduino
Datasheet:
Part Number:
Description:
ATMEGA328 MCU IC W/ Arduino UNO Bootloader
Manufacturer:
Arduino
Datasheet:
Part Number:
Description:
Memory Cards MICRO SD CARD 1GB WITH SD ADAPTER
Manufacturer:
Arduino