AvaLAN Wireless AW900mSPI-10 - Manual (Page 27)

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AW900mSPI User’s Manual
13. Deassert /CS_BB.
14. Wait for Connected Flag to be set
The AW900mSPI is now initialized and connected, ready to send and receive data.
Send Data Example (AP Side)
1. If Connected Flag is clear or FIFO Full Flag is set then end.
2. Else assert /CS_BB (drive line low) and issue
setPacket (0x8A) command
and delay for 4 µs.
3. Send first byte indicating if a broadcast packet or a unicast packet.
4. Send two bytes indicating data size in bytes.
5. Send all data bytes
6. Deassert /CS_BB (drive line high) and delay for 6 µs.
Get Data Example (AP Side)
1. If Data Ready Flag is set assert /CS_BB (drive line low) and issue getPacket
(0x0A) command and delay for 4 µs.
2. Gets first byte to determine what SU sent the packet.
3. Get next two bytes to determine the packet size in bytes.
4. Get all data bytes
5. Deassert /CS_BB (drive line high) and delay for 6 µs.
6. If Data Ready is still set then repeat all steps.
RSSI Example
1. Assert /CS_BB (drive line low) and issue getRSSIreadings (0x09) command
and delay for 4 µs.
2. Send first byte to tell XC1220 what step size and number of samples to use.
3. Get two bytes to determine the Base Frequency multiplier.
4. Get two bytes to determine the Numerator and Denominator for frequency
calculations.
5. Get one byte to determine how many channel markers there are.
6. Get all channel markers.
7. Wait for Data Ready to be set.
8. Get two bytes to determine the number of data points to be read.