ATMEGA128RFA1-ZU Atmel, ATMEGA128RFA1-ZU Datasheet - Page 388

• 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

25.7 Transmission Modes
388
4
5
6
7
Assembly Code Example
wait2:
in r16,TWCR
sbrs r16,TWINT
rjmp wait2
in r16,TWSR
andi r16, 0xF8
cpi r16, MT_SLA_ACK
brne ERROR
ldi r16, DATA
out TWDR, r16
ldi r16, (1<<TWINT)|(1<<TWEN)
out TWCR, r16
wait3:
in r16,TWCR
sbrs r16,TWINT
rjmp wait3
in r16,TWSR
andi r16, 0xF8
cpi r16, MT_DATA_ACK
brne ERROR
ldi r16,(1<<TWINT)|(1<<TWEN)|
out TWCR, r16
ATmega128RFA1
(1<<TWSTO)
The TWI can operate in one of four major modes. These are named Master Transmitter
(MT), Master Receiver (MR), Slave Transmitter (ST) and Slave Receiver (SR). Several
of these modes can be used in the same application. As an example, the TWI can use
MT mode to write data into a TWI EEPROM, MR mode to read the data back from the
EEPROM. If other masters are present in the system, some of these might transmit
data to the TWI, and then SR mode would be used. It is the application software that
decides which modes are legal.
The following sections describe each of these modes. Possible status codes are
described along with figures detailing data transmission in each of the modes. These
figures contain the following abbreviations:
S:
R:
Data:
SLA:
A
In
that the TWINT Flag is set. The numbers in the circles show the status code held in
TWSR, with the prescaler bits masked to zero. At these points, actions must be taken
by the application to continue or complete the TWI transfer. The TWI transfer is
suspended until the TWINT Flag is cleared by software.
When the TWINT Flag is set, the status code in TWSR is used to determine the
appropriate software action. For each status code, the required software action and
_
:
Figure 25-12 on
START condition
Read bit (high level at SDA)
8-bit data byte
Slave Address
Not acknowledge bit (high level at SDA)
C Example
while (!(TWCR & (1<<TWINT)));
if ((TWSR & 0xF8) != MT_SLA_ACK)
TWDR = DATA;
TWCR = (1<<TWINT) | (1<<TWEN);
while (!(TWCR & (1<<TWINT)));
if ((TWSR & 0xF8) != MT_DATA_ACK)
TWCR = (1<<TWINT)|(1<<TWEN)|
(1<<TWSTO);
ERROR();
ERROR();
page 390 to
Figure 25-18 on
Rs:
W:
P:
A:
REPEATED START condition
Write bit (low level at SDA)
STOP condition
Acknowledge bit (low level at SDA)
page 400 circles are used to indicate
Comments
Wait for TWINT Flag set. This
indicates that the SLA+W has been
transmitted, and ACK/NACK has
been received.
Check value of TWI Status Register.
Mask prescaler bits. If status different
from MT_SLA_ACK go to ERROR
Load DATA into TWDR Register.
Clear TWINT bit in TWCR to start
transmission of data
Wait for TWINT Flag set. This
indicates that the DATA has been
transmitted, and ACK/NACK has
been received.
Check value of TWI Status Register.
Mask prescaler bits. If status different
from MT_DATA_ACK go to ERROR
Transmit STOP condition
8266B-MCU Wireless-03/11