Holtek BA45F56 Series Function Description page 5

OM[2:0]=000b
FIFO Mode
The device will automatically load the default values after RF power on after which it will enter the
Deep Sleep Mode. To use the FIFO Mode to transmit or receive data, use the following steps.
Step 1. Setup parameters: Use the SPI interface to program the internal control registers. For example,
frequency (D_N, D_K), modulation parameter (FSCALE), data rate (DTR), etc. For parameter
setting details refer to the datasheet.
Step 2. Setup the synchronisation characters: Program the TXPMLEN and RXPMLEN registers to
setup the length of the preamble signal to be transmitted or received. Use the SPI command
to write the SYNCWORD Command (0x10).
Step 3. Setup the data format: Program the PKT1~PKT9 registers.
Step 4. Setup the FIFO Mode: Set DIR_EN to 0.
Step 5. Reset the FIFO index to zero: Use the SPI command TX/RX FIFO Address Pointer Reset
Command (0x09/0x89) and then set TXFFSA to 0.
Step 6. Write the data to be transmitted into the FIFO: Use the SPI command TX FIFO Write
Command (0x11) to write the data to be transmitted into the FIFO. If data is to be received
do not execute this step.
Step 7. Start the transmit/receive mode: Use the SPI shortcut command TX/RX Mode (0x0E/0x8E)
to enable this mode.
AN0571EN V1.00
BA45F56xx Wireless Transceiver Application
Deep Sleep
Idle
Idle
Idle
OM[1:0]=00b
OM[2]=1
TX
Figure 3. Direct Mode State Diagram
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Power Down
Power On
Deep Sleep
Deep Light
Calibration
Sleep Sleep
enabled
Auto (calibration completed)
Light Sleep
OM[1:0]=01b (RX)
OM[1:0]=11b (TX)
(wait~35μs)
Standby
OM[2]=1
RX
Calibrations
OM[2:0]=000b
November 5, 2020