Rev. 1.10
214
October 23, 2020
Rev. 1.10
215
October 23, 2020
BC66F5652
2.4GHz RF Transceiver A/D Flash MCU
BC66F5652
2.4GHz RF Transceiver A/D Flash MCU
Security Function
The security function, which is optional and is set by the WHT_EN bit, is implemented by LFSR
(Data Whitening/De-Whitening) for the RF Transceiver. The formula listed below calculates both of
payload and CRC field (Data In). The Packet Encryption Key is WHT_PTN[6:0], its initial value is
WHTSD[6:0].
g(X) = X
7
+ X
4
+ 1
X
0
: WHT_PTN[0]
X
1
: WHT_PTN[1]
X
2
: WHT_PTN[2]
X
3
: WHT_PTN[3]
X
4
: WHT_PTN[4]
X
5
: WHT_PTN[5]
X
6
: WHT_PTN[6]
Data FIFO
TX/RX FIFO
The RF Transceiver contains three levels of 32-byte data FIFO for transmitting payload of TX and
receiving payload of RX.
• TX three levels, 32-byte FIFO
• RX three levels, 32-byte FIFO
RX FIFO 0 (32 bytes)
RX FIFO 1 (32 bytes)
RX FIFO 2 (32 bytes)
TX FIFO 0 (32 bytes)
TX FIFO 1 (32 bytes)
TX FIFO 2 (32 bytes)
SPI
TX/RX FIFO Controller
Data
Control
Both FIFOs have a controller and are accessible through the SPI by using dedicated SPI commands.
The FIFOs are accessible in both PTX and PRX mode. TX FIFO and RX FIFO each have three
levels and each FIFO level size is 32 bytes at most.
Users can use three commands to write TX payloads into TX FIFO, which are Write TX FIFO with
Auto-ACK Mode Command and Write TX FIFO with No-Auto-ACK Mode Command for the PTX
device, and Write Pipe N ACK Payload Command for the PRX device. If the TX FIFO in a PTX
device contains more than one payload to a pipe, the payloads will be handled in a “first in - first
