Si4356-DK

Rev. 1.2

7

5.3. Legacy Encoder Packet

This packet is for demonstrating on the receiver side the reception of legacy packets that were not optimized for RF

communication. The packet structure follows the structure of the bit stream generated by a Holtek HT6P20

encoder chip. The figure below describes the packet structure. The only difference is that this demo

implementation uses 22 address bits and 2 data bits. The address bits are the 22 LSb bits of the four byte factory

programmed unique ID of the Si4010. The data bits reflect which button was pressed. The bit structure can be

observed in the fixed anti-code pattern. One bit takes three clock cycles. The nominal value of fosc is 3 kHz.

Figure 4. A Complete Code word of the HT6P20D

6. Receiver Node

The receiver node is based on the EZRadio Si4356 standalone sub-GHz receiver IC. Standalone means that the

Si4356 is pin-strap configurable; there is no need for an external MCU to configure and control the receiver.

Integrated configuration tables allow the Si4356 to be completely configured using the four selector pins. The state

of each of these pins is read internally at startup and used to determine which pre-loaded configuration should be

used. After loading the configuration, the receiver automatically starts reception. The receiver demodulates the

incoming data asynchronously by oversampling the incoming transmission. The resulting demodulated signal is

output to the system MCU through a data output pin.

6.1. The RFStick platform

Figure 5. EZRadio RFStick Receiver Board (P/N 4356-LED-434-DIR)

The RFStick is a basic demo system for the evaluation of the EZradio chips. The board has two main parts, the

MCU part and the radio part. The MCU part of the board contains a Silabs C8051F930 MCU and basic human

interface devices (four push-buttons, four LEDs, four switches and a buzzer). Additionally the MCU part of the

Si4356 RFStick has four four-position switches (SEL0-SEL3) to configure the radio. The radio part contains the

EZRadio chip, the matching circuit and the antenna. The RF input is selectable via a 0

antenna and a 50

the Si4356 EZRadio chip via four GPIOs according to the Table 8. The RF section of the board can be broken off

along a perforation and installed in the user's own hardware as a radio module. In this case the radio can be

configured via solderable jumpers on the RF section. These solderable jumpers have to be left open when the RF