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5.2. Example Projects Description
The general structure of an example project is shown in Figure 26. All the tasks are separated into two groups: the
"Hardware Initialization" part and the "Main Process" part. The Host MCU related tasks initialize the physical
interface between the radio and the controller unit, including the SPI lines (SCLK, SDI, SDO, NSEL) and general
I/O ports (SDN, NIRQ). After the interface has been initialized, the internal timer module is initialized to provide
precise timing for the handlers. Some example projects, such as the un-modulated carrier or the pseudo random
transmission projects, don't use handlers due to their simplicity. Handlers are for monitoring and changing the state
of the WMB peripherals. It is necessary to initialize the required handlers before using them. The radio related
tasks prepare the radio for the communication. The shutdown state may be entered by driving the SDN pin high.
When coming out of the shutdown state, a power on reset will be initiated along with the internal calibrations. After
the "POR" and the "BOOT" process, it is necessary to initialize the radio with the RF settings. It is highly
recommended to use the configuration header file (radio_config.h) generated by the Wireless Development Suite.
Manual editing in the header file can cause discrepancies and prevent the radio from working correctly. After the
radio is initialized, the Main Process has to continuously update the peripheral handlers and process the user
application code. The radio can be controlled from a high level due to the layered, customizable, user friendly radio
driver module.
Figure 26. General Structure of an Example Project
The example codes can be exported from the Wireless Development Suite software. Since the "radio_config.h"
configuration header file is highly customizable by the WDS software tool, there are no dedicated default
parameters for the example projects.
Summary of Contents for Si4455 Series
Page 8: ...AN692 8 Rev 0 4 Figure 6 Device Configuration Options ...
Page 22: ...AN692 22 Rev 0 4 Figure 21 Supply Current versus Time Diagram from Shutdown to RX State ...
Page 23: ...AN692 Rev 0 4 23 4 4 Radio Chip Waking Up Figure 22 Radio Wake Up Process ...
Page 35: ...AN692 Rev 0 4 35 Figure 32 Transmission Flowchart ...
Page 39: ...AN692 Rev 0 4 39 Figure 33 Reception Flowchart ...
Page 41: ...AN692 Rev 0 4 41 Figure 34 Bidirectional Variable Packet Example Project Flowchart ...
Page 47: ...AN692 Rev 0 4 47 Figure 41 Long Packet Transmission Flowchart ...
Page 48: ...AN692 48 Rev 0 4 Figure 42 Long Packet RX Flowchart ...
