AT86RF230_09 ATMEL [ATMEL Corporation], AT86RF230_09 Datasheet - Page 45

• 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]

8 Functional Description
8.1 Introduction - Frame Format
Figure 8-1 IEEE 802.15.4-2003 Frame Format – PHY Layer Frame Structure
Figure 8-2 IEEE 802.15.4-2003 Frame Format – MAC Layer Frame Structure
8.1.1 PHY Protocol Layer Data Unit (PPDU)
8.1.1.1 Synchronization Header (SHR)
5131E-MCU Wireless-02/09
Figure 8-1 provides an overview of the physical layer frame structure as defined by the
IEEE 802.15.4-2003 standard. Figure 8-2 shows details of the defined MAC layer frame
structure.
The SHR consists of a four-octet preamble field (all zero), followed by a single SFD
octet which has the predefined value 0xA7. When transmitting, the SHR is automatically
generated by the AT86RF230, and prefixed to the frame that has been read from the
Frame Buffer. The transmission of the SHR requires 160 µs (10 symbols). This allows
the microcontroller to initiate a transmission and to start downloading the frame
contents subsequently. Note, that in this case the SPI transfer rate must be equal or
faster than the PHY data rate.
During frame reception, the SHR is used for PHY synchronization purposes. In Basic
Operating Mode an RX_START interrupt is issued 8 µs after detection of the SFD field.
AT86RF230
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