ATmega128RZAV Atmel Corporation, ATmega128RZAV Datasheet - Page 266
ATmega128RZAV
Manufacturer Part Number
ATmega128RZAV
Description
Manufacturer
Atmel Corporation
Specifications of ATmega128RZAV
Flash (kbytes)
128 Kbytes
Max. Operating Frequency
16 MHz
Max I/o Pins
54
Spi
3
Twi (i2c)
1
Uart
2
Adc Channels
8
Adc Resolution (bits)
10
Adc Speed (ksps)
15
Analog Comparators
1
Crypto Engine
No
Sram (kbytes)
8
Eeprom (bytes)
4096
Operating Voltage (vcc)
1.8 to 3.6
Timers
6
Frequency Band
2.4 GHz
Max Data Rate (mb/s)
0.25
Antenna Diversity
No
External Pa Control
No
Power Output (dbm)
3
Receiver Sensitivity (dbm)
-101
Receive Current Consumption (ma)
16.0
Transmit Current Consumption (ma)
17.0
Link Budget (dbm)
104
- Current page: 266 of 448
- Download datasheet (8Mb)
24.9
24.9.1
24.9.2
2549N–AVR–05/11
Register Description
TWBR – TWI Bit Rate Register
TWCR – TWI Control Register
•
This is summarized in
Figure 24-21. Possible Status Codes Caused by Arbitration
• Bits 7:0 – TWI Bit Rate Register
TWBR selects the division factor for the bit rate generator. The bit rate generator is a frequency
divider which generates the SCL clock frequency in the Master modes. See
Unit” on page 247
The TWCR is used to control the operation of the TWI. It is used to enable the TWI, to initiate a
Master access by applying a START condition to the bus, to generate a Receiver acknowledge,
to generate a stop condition, and to control halting of the bus while the data to be written to the
bus are written to the TWDR. It also indicates a write collision if data is attempted written to
TWDR while the register is inaccessible.
Bit
(0xB8)
Read/Write
Initial Value
Bit
(0xBC)
Read/Write
Initial Value
Two or more masters are accessing different slaves. In this case, arbitration will occur in the
SLA bits. Masters trying to output a one on SDA while another Master outputs a zero will
lose the arbitration. Masters losing arbitration in SLA will switch to Slave mode to check if
they are being addressed by the winning Master. If addressed, they will switch to SR or ST
mode, depending on the value of the READ/WRITE bit. If they are not being addressed, they
will switch to not addressed Slave mode or wait until the bus is free and transmit a new
START condition, depending on application software action.
START
TWBR7
TWINT
R/W
R/W
7
0
7
0
for calculating bit rates.
Address / General Call
Figure
Direction
received
Own
TWBR6
TWEA
Yes
R/W
R/W
Arbitration lost in SLA
6
0
6
0
SLA
24-21. Possible status values are given in circles.
Write
Read
ATmega640/1280/1281/2560/2561
TWBR5
TWSTA
No
R/W
R/W
5
0
5
0
TWBR4
TWSTO
R/W
R/W
4
0
4
0
68/78
38
B0
Arbitration lost in Data
TWBR3
TWWC
TWI bus will be released and not addressed slave mode will be entered
A START condition will be transmitted when the bus becomes free
Data byte will be received and NOT ACK will be returned
Data byte will be received and ACK will be returned
Last data byte will be transmitted and NOT ACK should be received
Data byte will be transmitted and ACK should be received
R/W
R
3
0
3
0
Data
TWBR2
TWEN
R/W
R/W
2
0
2
0
TWBR1
R/W
R
1
0
1
–
0
“Bit Rate Generator
TWBR0
TWIE
R/W
R/W
0
0
0
0
STOP
TWBR
TWCR
266
Related parts for ATmega128RZAV
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
INTERVAL AND WIPE/WASH WIPER CONTROL IC WITH DELAY
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
Low-Voltage Voice-Switched IC for Hands-Free Operation
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
MONOLITHIC INTEGRATED FEATUREPHONE CIRCUIT
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
AM-FM Receiver IC U4255BM-M
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
Monolithic Integrated Feature Phone Circuit
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
Multistandard Video-IF and Quasi Parallel Sound Processing
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
High-performance EE PLD
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
8-bit Flash Microcontroller
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
2-Wire Serial EEPROM
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
U6046BREAR WINDOW HEATING TIMER / LONG-TERM TIMER
Manufacturer:
ATMEL Corporation
Datasheet: