RF3000PCBA RFMD [RF Micro Devices], RF3000PCBA Datasheet - Page 12

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

The RF3000 signals that it is nearing the end of the preamble and header transmission by driving TX RDY high. This sig-
nals the user that transmission data clocks are coming. When the RF3000 is ready to transmit data it will begin clocking
transmit data. Data to be transmitted should be present on TX DATA on the rising edge of DATA CLK. The RF3000 will
only clock in the number of data-bits to fill the specified transmission time.
IEEE802.11b DSSS Transmission Summary
1. TX Mode different:
2. TX Length different:
3. Drive TX PE High and wait for TX RDY to go High.
4. Transmit data must be valid on the rising edge of DATA CLK.
Figure 8 shows the primary interface mode for the RF3000 TX Data port.
Figure 8. IEEE802.11b Transmit Timing Overview
The RF3000 has provision for an alternate Transmit Data port interface. In the transmit interface an extra clock is
asserted after TXRDY goes ‘high' and before the first TX data clock on DATA CLK, see Figure 8a. The alternate Transmit
interface is enabled by writing 0x08 into RF3000 Register 0x1C.
Figure 8a. Alternate Transmit Interface
11-332
RF3000
Write value to the mode register according to table.
Write the number of uS to transmit in the TX length registers.
DATA CLK
TX DATA
TX RDY
RX PE
TX PE
TX Q
CCA
TX I
DATA CLK
TX DATA
TX RDY
RX PE
TX PE
TX Q
CCA
TX I
and Header
Preamble
Preamble and
Header
Rate Determined from Control Port Register 1
Rate Determined from Control Port Register 1
Data
Data
Rev A4 031216