A N 6 9 2
2
Rev 0.4
The four GPIO signals’ primary function is push button input to the MCU (PB1–PB4), so these signals are not
connected to the EZRadio chip by default (represented by x in Table 1). The user can connect them by soldering in
jumpers across the appropriate pins of J3.
Table 1. Connections between the EZRadio Chip and the MCU
Si4355, Si4455
RFStick
C80C51F930
Pin Number
Pin Name
Pin Function
Connections
across J3
Signal Name
Pin Name
EP, 1, 6, 9
GND
Ground
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
7 x 8
GPIO_3/PB4
P0.3
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 ...
