RF3000PCBA RFMD [RF Micro Devices], RF3000PCBA Datasheet - Page 17

• Manufacturer Part Number: RF3000PCBA
• Description: SPREAD-SPECTRUM BASEBAND MODEM
• Manufacturer: RFMD [RF Micro Devices]

IEEE802.11b DSSS Receive Summary
1. Drive RXPE High.
2. RF3000 looks for incoming valid Barker Code.
3. RF3000 sets ACQ bit in Register 0x01.
4. When the Start Frame Delimiter is identified, the RF3000 sets the SFD bit in Register 0x01.
5. RF3000 Extracts Header information.
6. This will be followed by 16 bit times of no clock transitions.
7. RF3000 Drives RXRDY high, and clocks Received Data on the rising edge of DATA CLK.
8. RF3000 Drives RXRDY low at the end of the data packet.
Figure 13. IEEE802.11b Receive Timing Overview
The RF3000 has provision for an alternate Receive Data port interface. In the receiver interface, the DATACLK is
inverted, and an extra clock is asserted after RXRDY goes 'low' indicating the end of the received packet, see Figure
13a. The alternate Transmit interface is enabled by writing 0x08 into RF3000 Register 0x1C.
Figure 13a. Alternate Receiver Interface
Rev A4 031216
This information is copied into the RF3000 RX Status, Service fields and presented on the RXDATA Pin with Clocks on
DATA CLK.
DATACLK
RXDATA
RXRDY
RXPE
DATACLK
RXDATA
RXRDY
RXPE
Header
32CLK
Preamble and
Cycles
Data
Extraction
Header
Header
32CLK
Preamble and
Cycles
Data
Extraction
Header
Rate Determined from Received IEEE802.11 Signal Field
Rate Determined from Received IEEE802.11 Signal Field
Data
Data
RF3000
11-337