Si4010-RC-DEMO

Rev. 0.2

3

3. RF Parameters

The demo kit uses the following RF parameters according to the kit’s frequency band.

The modulation is FSK.

4. Transmitter Side Program

The Si4010 in the key fob programmed with the rke_demo_2 program. Since the program is burned in the NVM

(OTP) memory of the Si4010, it cannot be changed. The whole rke_demo_2 software project can be found in the

example programs package of the Si4010. It is available at the web page

http://www.silabs.com/products/wireless/EZRadio/Pages/Si4010.aspx on the Tools tab.

The key fob transmits an RF packet three times each time a button is pressed, and it also blinks the LED on the key

fob. The packet structure is as follows:

Symbol rate is 9.6 kBd.

Each packet contains 18 additional bytes that are not received by the receiver of this demo. These additional bytes

are AES-encrypted and are used by the AES demo kit. See details in the user’s guide of the AES demo kit (P/N

4010-AESK1W-434).

In the key fob program the frequency and deviation is pin-selected by the pcb layout. This operating frequency is

indicated on a label on the back of the key fob pcb.

The 316.667 MHz key fob is available in the 4010-AESK1W-315 demo kit or separately from Silicon Labs.

The key fob’s default modulation is FSK but if the middle button is pressed and held during battery insertion, the

modulation will be OOK until the next powerdown (battery removal).

Kit Part Number

Center Frequency

Deviation

EZR-LEDK1W-434

433.92 MHz

EZR-LEDK1W-868

868.30 MHz

EZR-LEDK1W-917

917.00 MHz

Number of Bytes

Field Name

Description

13

Preamble

0xaa

2

Sync

0x2d, 0xd4

4

Chip ID

Unique, factory-burned chip ID

1

Status

Lower 5 bits are the button information

2

Packet count

Rolling counter for PER measurement

2

CRC-16

Generator X16+X15+X2+1, start value 0xFFFF

GPIO8

GPIO9

Center Frequency

Deviation

High

Low

316.66 MHz

High

High

433.92 MHz

Low

High

868.30 MHz

Low

Low

917.00 MHz