CC2430
Radio : Transmit mode
Data received over RF
SFD
Preamble
SFD Length
MAC Protocol Data Unit (MPDU) with correct address
Address
recognition OK
FIFO
FIFOP , if threshold
higher than frame length
FIFOP , if threshold
lower than frame length
Data received over RF
Preamble
SFD Length
MAC Protocol Data Unit (MPDU) with wrong address
Address
recognition fails
SFD
FIFO
FIFOP
Figure 35: SFD, FIFO and FIFOP activity examples during receive
Figure 36: Example of status activity when reading RXFIFO.
14.9 Transmit mode
See section 14.17.1 on page 163 for more
information on TXFIFO underflow.
During transmit the RFSTATUS.FIFO and
RFSTATUS.FIFOP bits are still only related to
the RXFIFO. The RFSTATUS.SFD bit is
however active during transmission of a data
As can be seen from comparing Figure 35 and
Figure 37, the RFSTATUS.SFD bit behaves
frame,
as
shown
in
very
similarly
during
reception
and
Figure 37.
transmission of
a
data frame. If the
RFSTATUS.SFDbits of the transmitter and the
receiver are compared during the transmission
of a data frame, a small delay between 3.076
µs and 3.284 µs can be seen because of
bandwidth limitations in both the transmitter
and the receiver.
The RFIF.IRQ_SFD interrupt flag goes high
and the RF interrupt is requested when the
SFD field has been completely transmitted. It
goes low again when the complete MPDU (as
defined by the length field) has been
transmitted or if an underflow is detected. The
interrupt RFERR is then asserted if enabled.
CC2430 Data Sheet (rev. 2.1) SWRS036F
Page 159 of 211
TAOS [ TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS ]
