Silicon Laboratories SI4421 Manual do Utilizador descarregar pdf (Página 11)

RF WIRELESS FOUNDATION COURSE BOOK ONE

Rev. 0.1 11

Exercise 2—How to Set the Second EZLink Module as a CW Receiver

The example project shows a very simple application: the receiver chain of the transceiver chip on the EZLink

Si4421 module is continuously enabled in raw data mode (FIFO is not used: only the DATA pin is used for receiving

the data). The software switches the LEDs according the received bits:

 If it receives 1 it illuminates the RC LED.

 If it receives 0 it illuminates the TR LED.

This project provides the ability to check the CW transmitter application if the modules are configured to the same

center frequency.

To work with this example, please follow the following steps:

1. Use the same project as in Exercise1:

“C:\Silabs\SRW\RF_Basics_Lesson\Lesson2”.

2. Uncomment the “#define CW_RECEIVER_MODE” line and comment the

“#define CW_TRANSMITTER_MODE” definition for compilation of the source code as a CW receiver.

3. Compile the project and program it to a second EZLink Si4421 module.

4. If there is no transmitted data on the given center frequency, then the receiver receives only noise, which is

represented randomly changing 0 and 1. This can be easily identified, because both LEDs blink at the same

time (this is because the signal is changing so often that it appears that both LEDs are on).

5. If the previously programmed CW Transmitter board is also switched on, then pressing and releasing the SW2

push button will result in the LEDs blinking accordingly on the CW receiver board also.

Figure 14. Lesson 2 (CW Receiver)

1. Select CW_TRANSMITTER_MODE

2. Compile the project

3. Connect to the programmer

5. Load to the MCU

1 2 ... 6 7 8 9 10 11 12 13 14 15 16

Sem comentários

Silicon Laboratories SI4421 Manual do Utilizador Página 11