BC9824 Datasheet, PDF (6/22 Pages) Holtek Semiconductor Inc – Low Power High Performance Low Power High Performance

BC9824
Standby-II Mode
In standby-II mode more clock buffers are active
than in standby-I mode and much more current is
used. Standby-II occurs when CE is held high on a
PTX device with empty TX FIFO. If a new packet
is uploaded to the TX FIFO in this mode, the device
will automatically enter TX mode and the packet is
transmitted.
TX Mode
• PTX device (PRIM_RX=0)
The TX mode is an active mode where the PTX
device transmits a packet. To enter this mode from
power down mode, the PTX device must have the
PWR_UP bit set high, PRIM_RX bit set low, a
payload in the TX FIFO, and a high pulse on the
CE for more than 10µs.
The PTX device stays in TX mode until it finishes
transmitting the current packet. If CE = 0 it returns
to standby-I mode. If CE = 1, the next action is
determined by the status of the TX FIFO. If the
TX FIFO is not empty the PTX device remains in
TX mode, transmitting the next packet. If the TX
FIFO is empty the PTX device goes into standby-II
mode. It is important to never stay in TX mode for
more than 4ms at one time.
If the auto retransmit is enabled (EN_AA=1) and
auto acknowledge is required (NO_ACK=0), the
PTX device will enter TX mode from standby-I
mode when ARD elapsed and number of retried is
less than ARC.
• PRX device (PRIM_RX=1)
The PRX device will enter TX mode from RX
mode only when EN_AA=1 and NO_ACK=0 in
received packet to transmit acknowledge packet
with pending payload in TX FIFO.
RX Mode
• PRX device (PRIM_RX=1)
The RX mode is an active mode where the BC9824
radio is configured to be a receiver. To enter this
mode from standby-I mode, the PRX device must
have the PWR_UP bit set high, PRIM_RX bit set
high and the CE pin set high. Or PRX device can
enter this mode from TX mode after transmitting
an acknowledge packet when EN_AA=1 and NO_
ACK=0 in received packet.
In this mode the receiver demodulates the signals
from the RF channel, constantly presenting the
demodulated data to the packet processing engine.
The packet processing engine continuously
searches for a valid packet. If a valid packet is
found (by a matching address and a valid CRC)
the payload of the packet is presented in a vacant
slot in the RX FIFO. If the RX FIFO is full, the
received packet is discarded.
The PRX device remains in RX mode until the
MCU configures it to standby-I mode or power
down mode.
In RX mode a carrier detection (CD) signal is
available. The CD is set to high when a RF signal
is detected inside the receiving frequency channel.
The internal CD signal is filtered before presented
to CD register. The RF signal must be present for
at least 128 µs before the CD is set high.
• PTX device (PRIM_RX=0)
The PTX device will enter RX mode from TX
mode only when EN_AA=1 and NO_ACK=0 to
receive acknowledge packet.
Rev. 1.00
6
October 20, 2015