AT86RF230_09 ATMEL [ATMEL Corporation], AT86RF230_09 Datasheet - Page 75

• Manufacturer Part Number: AT86RF230_09
• Description: Low Power 2.4 GHz Transceiver for ZigBee, IEEE 802.15.4, 6LoWPAN, RF4CE and ISM
• Manufacturer: ATMEL [ATMEL Corporation]

10 Radio Transceiver Usage
10.1 Frame Receive Procedure
10.2 Frame Transmit Procedure
5131E-MCU Wireless-02/09
This section describes basic procedures to receive and transmit frames using the
AT86RF230. For a detailed programming description refer to application note AVR2009
“AT86RF230 – Software Programming Model”.
While in state RX_ON the radio transceiver searches for incoming frames on the
selected channel. A detection of a valid IEEE 802.15.4 frame is indicated by an IRQ_2
(RX_START) interrupt. The frame reception is completed when issuing the IRQ_3
(TRX_END) interrupt. Waiting for IRQ_3 (TRX_END) interrupt before uploading the
frame to the microcontroller is recommended for operations considered to be non time
critical. Figure 9-6 illustrates the frame receive procedure.
Figure 9-6. Frame Receive Procedure - Transactions between AT86RF230 and
Microcontroller
Critical protocol timing could require starting the frame upload as soon as possible. The
first byte of the frame data can be read 32 µs after the IRQ_2 (RX_START) interrupt.
The microcontroller must ensure to read slower than the frame is received. Otherwise,
the Frame Buffer wills under run, IRQ_6 (TRX_UR) interrupt is issued. The frame data
are not valid anymore and need to read again. The LQI byte can be uploaded to the
microcontroller after the IRQ_3 (TRX_END) interrupt was issued.
A frame transmission comprises two actions, a frame download to the Frame Buffer and
the transmission of the Frame Buffer content. Both actions can be run in parallel if
required by critical protocol timing.
Figure 9-7 illustrates the frame transmit procedure, when downloading and transmitting
the frame consecutively. After a frame download by a Frame Buffer write access, the
frame transmission is initiated by asserting pin SLP_TR or writing the TRX command
TX_START to register 0x02 (TRX_STATE), while the radio transceiver is in state
PLL_ON. The completion of the transmission is indicated by an IRQ_3 (TRX_END)
interrupt.
AT86RF230
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