ATTINY26-16PJ Atmel, ATTINY26-16PJ Datasheet - Page 19

• Manufacturer Part Number: ATTINY26-16PJ
• Description: ID MCU AVR 2K 5V 16MHZ 20-DIP
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY26-16PJ

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 16
• Program Memory Size: 2KB (1K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 11x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

EEPROM Data
Register – EEDR
EEPROM Control
Register – EECR
1477K–AVR–08/10
• Bit 7..0 – EEDR7..0: EEPROM Data
For the EEPROM write operation, the EEDR Register contains the data to be written to the
EEPROM in the address given by the EEAR Register. For the EEPROM read operation, the
EEDR contains the data read out from the EEPROM at the address given by EEAR.
• Bit 7..4 – RES: Reserved Bits
These bits are reserved bits in the ATtiny26(L) and will always read as zero.
• Bit 3 – EERIE: EEPROM Ready Interrupt Enable
When the I-bit in SREG and EERIE are set (one), the EEPROM Ready Interrupt is enabled.
When cleared (zero), the interrupt is disabled. The EEPROM Ready Interrupt generates a con-
stant interrupt when EEWE is cleared (zero).
• Bit 2 – EEMWE: EEPROM Master Write Enable
The EEMWE bit determines whether setting EEWE to one causes the EEPROM to be written.
When EEMWE is set (one), setting EEWE will write data to the EEPROM at the selected
address. If EEMWE is zero, setting EEWE will have no effect. When EEMWE has been set (one)
by software, hardware clears the bit to zero after four clock cycles. See the description of the
EEWE bit for an EEPROM write procedure.
• Bit 1 – EEWE: EEPROM Write Enable
The EEPROM Write Enable Signal – EEWE – is the write strobe to the EEPROM. When
address and data are correctly set up, the EEWE bit must be set to write the value in to the
EEPROM. The EEMWE bit must be set when the logical one is written to EEWE, otherwise no
EEPROM write takes place. The following procedure should be followed when writing the
EEPROM (the order of steps 2 and 3 is unessential):
1. Wait until EEWE becomes zero.
2. Write new EEPROM address to EEAR (optional).
3. Write new EEPROM data to EEDR (optional).
4. Write a logical one to the EEMWE bit in EECR.
5. Within four clock cycles after setting EEMWE, write a logical one to EEWE.
Caution: An interrupt between step 4 and step 5 will make the write cycle fail, since the
EEPROM Master Write Enable will time-out. If an interrupt routine accessing the EEPROM is
interrupting another EEPROM access, the EEAR or EEDR Register will be modified, causing the
interrupted EEPROM access to fail. It is recommended to have the Global Interrupt Flag cleared
during all the steps to avoid these problems.
When the access time (typically 8.3 ms) has elapsed, the EEWE bit is cleared (zero) by hard-
ware. The user software can poll this bit and wait for a zero before writing the next byte. When
EEWE has been set, the CPU is halted for two cycles before the next instruction is executed.
• Bit 0 – EERE: EEPROM Read Enable
Bit
$1D ($3D)
Read/Write
Initial Value
Bit
$1C ($3C)
Read/Write
Initial Value
MSB
R/W
R
7
0
7
–
0
R/W
R
6
0
6
–
0
R/W
R
5
0
5
–
0
R/W
R
4
0
4
–
0
EERIE
R/W
R/W
3
0
3
0
EEMWE
R/W
R/W
2
0
2
0
EEWE
R/W
R/W
1
0
1
0
EERE
LSB
R/W
R/W
0
0
0
0
EEDR
EECR
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