ATMEGA128RFA1-ZU Atmel, ATMEGA128RFA1-ZU Datasheet - Page 379

• Manufacturer Part Number: ATMEGA128RFA1-ZU
• Description: IC AVR MCU 2.4GHZ XCEIVER 64QFN
• Manufacturer: Atmel
• Series: ATMEGAr

Specifications of ATMEGA128RFA1-ZU

• Frequency: 2.4GHz
• Data Rate - Maximum: 2Mbps
• Modulation Or Protocol: 802.15.4 Zigbee
• Applications: General Purpose
• Power - Output: 3.5dBm
• Sensitivity: -100dBm
• Voltage - Supply: 1.8 V ~ 3.6 V
• Current - Receiving: 12.5mA
• Current - Transmitting: 14.5mA
• Data Interface: PCB, Surface Mount
• Memory Size: 128kB Flash, 4kB EEPROM, 16kB RAM
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-VFQFN, Exposed Pad
• Rf Ic Case Style: QFN
• No. Of Pins: 64
• Supply Voltage Range: 1.8V To 3.6V
• Operating Temperature Range: -40°C To +85°C
• Svhc: No SVHC (15-Dec-2010)
• Rohs Compliant: Yes
• Processor Series: ATMEGA128x
• Core: AVR8
• Data Bus Width: 8 bit
• Program Memory Type: Flash
• Program Memory Size: 128 KB
• Data Ram Size: 16 KB
• Interface Type: JTAG
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 38
• Number Of Timers: 6
• Operating Supply Voltage: 1.8 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVR128RFA1-EK1
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

25.3.3 Address Packet Format
25.3.4 Data Packet Format
8266A-MCU Wireless-12/09
Figure 25-3. START, REPEATED START and STOP conditions
SDA
All address packets transmitted on the TWI bus are 9 bits long, consisting of 7 address
bits, one READ/WRITE control bit and an acknowledge bit. If the READ/WRITE bit is
set, a read operation is to be performed, otherwise a write operation should be
performed. When a Slave recognizes that it is being addressed, it should acknowledge
by pulling SDA low in the ninth SCL (ACK) cycle. If the addressed Slave is busy, or for
some other reason can not service the Master’s request, the SDA line should be left
high in the ACK clock cycle. The Master can then transmit a STOP condition, or a
REPEATED START condition to initiate a new transmission. An address packet
consisting of a slave address and a READ or a WRITE bit is called SLA+R or SLA+W,
respectively.
The MSB of the address byte is transmitted first. Slave addresses can freely be
allocated by the designer, but the address 0000 000 is reserved for a general call.
When a general call is issued, all slaves should respond by pulling the SDA line low in
the ACK cycle. A general call is used when a Master wishes to transmit the same
message to several slaves in the system. When the general call address followed by a
Write bit is transmitted on the bus, all slaves set up to acknowledge the general call will
pull the SDA line low in the ack cycle. The following data packets will then be received
by all the slaves that acknowledged the general call. Note that transmitting the general
call address followed by a Read bit is meaningless, as this would cause contention if
several slaves started transmitting different data.
All addresses of the format 1111 xxx should be reserved for future purposes.
Figure 25-4. Address Packet Format
SDA
All data packets transmitted on the TWI bus are nine bits long, consisting of one data
byte and an acknowledge bit. During a data transfer, the Master generates the clock
and the START and STOP conditions, while the Receiver is responsible for
acknowledging the reception. An Acknowledge (ACK) is signaled by the Receiver
SCL
SCL
START
START
Addr MSB
1
STOP
2
START
Addr LSB
7
REPEATED START
ATmega128RFA1
R/W
8
ACK
9
STOP
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