Examples for non-IEEE-802.15.4-compliant RX_AACK Configurations

In addition to the IEEE-802.15.4-compliant operation modes (refer to section Examples for IEEE 802.15.4 compliant RX_AACK Configuration), the AT86RF231 allows Handling Of Reserved Frame Types and Short Acknowledgment Timing, thus providing hardware support for proprietary MAC protocols.

Use Cases:

• CFG_NIEEE_ENABLE_RES_FT
• CFG_NIEEE_ENABLE_SHORTACKTIME

---

CFG_NIEEE_ENABLE_RES_FT

IEEE 802.15.4 defines the four frame types Beacon, Data, Ack and MAC Command. In extension to the standard, the frame filter of the AT86RF231 can be configured to handle reserved frames allowing the application of proprietary MAC protocols. Reserved frame types can be either interpreted as IEEE 802.15.4 Data frames or simply handled as non-IEEE-802.15.4-compliant frames. While interpreting reserved frame types as data frames enables the address filter and the automatic acknowledgement transmission of the RX_AACK. Frames handled as non-IEEE-802.15.4-compliant frames are bypassing filtering mechanisms and no acknowledgement is transmitted.

To enable the handling of reserved frame types in RX_AACK, a network device must be set up as a Normal Device, PAN Coordinator or Promiscuous Mode Device/Sniffer as described in Examples for IEEE 802.15.4 compliant RX_AACK Configuration with the difference that one must

1. Enable the upload of reserved frame types: upld_res_ft_mode = 1.
2. Configure the processing of reserved frame types: fltr_res_ft.

Parameters:

fltr_res_ft

Defines the handling of reserved frame type: 0: Only the FCS is checked, the TRX_IRQ_AMI will never be generated. 1: Frame will be filtered like IEEE 802.15.4 data frame.

Code example

    /* AT86RF231::[CONFIG] */
    trx_bit_write(SR_AACK_UPLD_RES_FT, 1);
    trx_bit_write(SR_AACK_FLTR_RES_FT, fltr_res_ft);

CFG_NIEEE_ENABLE_SHORTACKTIME

The IEEE 802.15.4 standard defines the latency, an Ack has to be sent after a frame has been received to tWaitAck=12 tsym when using unslotted and tWaitAck>=6 tsym when using slotted operation. In extension to the standard, the AT86RF231 may be configured to use an Ack latency of tWaitAck=2 tsym for both operation modes, allowing higher overall data throughputs when using proprietary MAC protocols. To configure the transceiver to use Short Ack Timing in RX_AACK receive mode, a network device must be set up as a Device, PAN Coordinator or Promiscuous Mode Device/Sniffer" as described in Examples for IEEE 802.15.4 compliant RX_AACK Configuration with the difference that Short Ack Timing must be enabled.

Code example

    /* AT86RF231::[CONFIG] */
    trx_bit_write(SR_AACK_ACK_TIME, 1);

---