AT86RF212 Atmel Corporation, AT86RF212 Datasheet - Page 57

• Manufacturer Part Number: AT86RF212
• Manufacturer: Atmel Corporation

Specifications of AT86RF212

• Max. Operating Frequency: 0 MHz
• Crypto Engine: AES
• Operating Voltage (vcc): 1.8 to 3.6
• Frequency Band: 700/800/900MHz
• Max Data Rate (mb/s): 1
• Antenna Diversity: No
• External Pa Control: Yes
• Power Output (dbm): 10
• Receiver Sensitivity (dbm): -110
• Receive Current Consumption (ma): 9.0
• Transmit Current Consumption (ma): 18 at 5dBm
• Link Budget (dbm): 120

5.2.4.1 Acknowledgment Timeout
5.2.4.2 Timing
8168C-MCU Wireless-02/10
Table 5-15. TX_ARET Interpretation of TRAC_STATUS Register Bits
A value of MAX_CSMA_RETRIES = 7 initiates an immediate TX_ARET transaction
without performing CSMA-CA. This supports beacon-enabled network operation.
Furthermore, by ignoring the value of MAX_FRAME_RETRIES, only a single attempt is
made to transmit the frame.
Note that the acknowledgment receive procedure does not overwrite the Frame Buffer
content. Transmit data in the Frame Buffer is not modified during the entire TX_ARET
transaction. Received frames, other than the expected ACK frame, are discarded
automatically.
If an acknowledgment (ACK) frame is expected after frame transmission, the
AT86RF212 sets a timeout until which a valid ACK frame must have been arrived. This
timeout macAckWaitDuration is defined according to [2] as follows:
macAckWaitDuration [symbol periods] =
aUnitBackoffPeriod + aTurnaroundTime + phySHRDuration + 6
where 6 represents the number of PHY header octets plus the number of PSDU octets
in an acknowledgment frame.
Specifically for the implemented PHY Modes (see section 7.1), this formula results in
the following values:
Note that for any PHY Mode the unit “symbol period” refers to the symbol duration of
the appropriate synchronization header; see section 7.1.3 for further information
regarding symbol period.
A timing example of a TX_ARET transaction is shown in Figure 5-13. In the example
shown, a data frame with an acknowledgment request is to be transmitted. The frame
transmission is started by pin 11 (SLP_TR). As MIN_BE is set to zero, the initial
CSMA-CA backoff period has length zero too. Thus, the CSMA-CA duration time
t
(assumed here), the frame is transmitted.
CSMA-CA
Value
•
•
0
1
3
5
7
BPSK:
O-QPSK:
only consists of 8 symbols of CCA measurement period. If CCA returns IDLE
Name
SUCCESS
SUCCESS_DATA_PENDING
CHANNEL_ACCESS_FAILURE
NO_ACK
INVALID
macAckWaitDuration = 120 symbol periods
macAckWaitDuration = 54 symbol periods
Description
The transaction was responded by a valid
ACK, or, if no ACK is requested, after a
successful frame transmission.
Equivalent to SUCCESS and indicating that
the “Frame Pending” bit (see section 6.1.2.2)
of the received acknowledgment frame was
set.
Channel is still busy after
MAX_CSMA_RETRIES of CSMA-CA.
No acknowledgement frame was received
during all retry attempts.
Entering TX_ARET mode until IRQ_3
(TRX_END).
·
phySymbolsPerOctet
AT86RF212
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