CS22220 Datasheet, PDF (12/34 Pages) Cirrus Logic – WIRELESS PCI/USB CONTROLLER

TXPEBB
TXD
TXRDY
CCA
BBRNW
nRESETBB
BBAS
nBBCS
Output
Baseband transmit power enable, an output from the MAC to the radio
baseband processor. When active, the baseband processor transmitter is
configured to be operational, otherwise the transmitter is in standby
mode.
Output
It is the serial data output from the MAC to the radio baseband processor.
The data is transmitted serially with the LSB first. The data is driven by
the MAC on the rising edge of TXCLK and is sampled by the radio
baseband processor on the falling or rising edge of TXCLK depending on
baseband requirements.
Input
Transmit data ready is an input to the MAC from the radio baseband
processor to indicate that the radio baseband processor is ready to
receive the data packet over the TXD signal. The signal is sampled by the
MAC on the rising edge of TXCLK.
Input
Clear channel assessment is an input from the radio baseband processor
to signal that the channel is clear to transmit. When this signal is a 0, the
channel is clear to transmit. When this signal is a 1, the channel is not
clear to transmit. This helps the MAC to determine when to switch from
receive to transmit mode.
Output
Baseband read/write is an output from the MAC to indicate the direction
of the SD bus when used for reading or writing data. This signal has to be
setup to the rising edge of BBSCLK for the baseband processor and is
driven on the rising edge of the ARMCLK corresponding the falling edge
of BBSCLK.
Output
Baseband reset is an output of the MAC to reset the baseband processor.
Output
Baseband address strobe is used to envelop the address or the data on
the BBSDX bus. A logic 1 envelops the address and a logic 0 envelops
the data. This signal has to be setup to the rising edge of BBSCLK for the
baseband processor and is driven on the falling edge of BBSCLK.
Output
Baseband chip select is an active low output to activate the serial control
port. When inactive the SD, BBSCLK, BBAS and BBRNW signals are
‘don’t cares’.
CS22220 Wireless PCMCIA Controller
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DS557PP2 Rev. 3.0