SI4455-2 Datasheet, PDF (4/9 Pages) Silicon Laboratories – The kits support use of the Wireless Development Suite

Si4455-2WayLink-DEMO
5. The RFStick Platform
Figure 1. RFStick
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 Silicon Labs C8051F930 MCU and basic
human interface devices (four push-buttons, four LEDs, four switches and a buzzer). The radio part contains the
EZRadio chip, the matching circuit, and the antenna. The RF output is selectable via a 0  resistor between a PCB
antenna and an optional (unpopulated) 50  SMA output connector. The MCU is connected to the EZRadio chip
via an SPI bus and some other GPIOs (see Table 2). The RF section of the board can be broken off along a
perforation between the two rows of J3 and installed in the user’s own hardware as a radio module by utilizing the
remaining row of J3.
Table 2 contains the signal connections between the EZRadio chip and the MCU:
Table 2. Connections between the EZRadio Chip and the MCU
Pin Number
EP, 1, 6, 9
Si4355, Si4455
Pin Name
GND
Pin Function
Ground
RFStick
C80C51F930
Connections Signal Name Pin Name
across J3
3–4
GND
GND
7, 8
VDD
Supply Voltage input
1–2
VDD
VDD
12
NIRQ
Interrupt output,
active low
19–20
NIRQ
P1.4
2
SDN
Shutdown input,
active high
5–6
SDN
P1.5
16
NSEL
SPI select input
11–12
NSEL
P1.3
13
SCLK
SPI clock input
17–18
SCLK
P1.0
15
SDI
SPI data input
13–14
MOSI
P1.2
14
SDO
SPI data output
15–16
MISO
P1.1
10
GPIO_0
General Purpose I/O 23 x 24
GPIO_0/PB1
P0.0
11
GPIO_1
General Purpose I/O 21 x 22
GPIO_1/PB2
P0.1
19
GPIO_2
General Purpose I/O
9 x 10
GPIO_2/PB3
P0.2
20
GPIO_3
General Purpose I/O
7x8
GPIO_3/PB4
P0.3
The four GPIO signals’ primary function is push button input to the MCU (PB1–PB4), so these signals are not
4
Rev. 0.4