RS-SAM3S-220X Redpine Signals, RS-SAM3S-220X Datasheet - Page 15

• Manufacturer Part Number: RS-SAM3S-220X
• Description: WiFi / 802.11 Modules Wi-Fi Card for Atmel SAM3S
• Manufacturer: Redpine Signals

Specifications of RS-SAM3S-220X

• Rohs: yes
• Protocol Supported: 802.11 b/g/n
• Frequency Band: 2.4 GHz
• Data Rate: 1 Mbps to 54 Mbps
• Interface Type: SPI
• Transmit Power (max): 17 dBm
• Antenna Connector Type: Chip
• Operating Supply Voltage: 3.3 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Modulation Technique: CCK, DSSS, OFDM
• Security: WEP 64/128 bit AES, WPA2-PSK

6.1 Host
6.1.1 Host SPI Interface
6.1.2 Host SPI Driver
6.1.3 RS-SAM3S-220X SPI Interface
6.1.4 Host Abstraction Layer (HAL)
6.1.5 Wireless Control Block (WCB)
6.1.6 Wi-Fi Control Frames
6.1.7 TCP/IP Control Frames
6.1.8 Station Management Entity (SME)
Redpine Signals, Inc.
The Host communicates with RS-SAM3S-220X using the SPI interface. A
driver on the Host takes care of the interaction with the Wi-Fi module through
the SPI Host interface.
The following sections explain in brief the various components.
The Host is any system that has applications being executed on it.
The SPI on the Host side provides an interface for the host to access the Wi-Fi
module. SPI on the Host acts as the master.
The SPI driver on the Host is a thin driver through which the applications
interact with the Wi-Fi module. The SPI driver uses the SPI host controller
driver on the Host to send/receive the data to/from the RS-SAM3S-220X
module and also to configure the same over the SPI interface.
The SPI on the RS-SAM3S-220X acts the SPI slave. It is a standard 4-wire
SPI and can support a maximum frequency of 25MHz.
The HAL abstracts the lower layers in the host interface with which the RS-
SAM3S-220X module is connected. The HAL interacts with the Wireless
Control Block layer for the processing of the frames obtained from or destined
to the Host.
The data from/to the Host is classified as Wi-Fi specific frames and TCP/IP
specific frames. The WCB layer processes the frame obtained and acts
accordingly. The functionality of the WCB module depends on the type of the
frame and the direction of the frame (in case of TCP/IP) as described below.
The WCB interprets the Wi-Fi control information from the Host and interacts
with the SME (Station Management Entity). Configuration of the RS-SAM3S-
220X module from the Host for Wi-Fi access is through SPI commands,
provided as an API set.
If the frames from the host are interpreted as TCP/IP specific frames then the
WCB interacts with the TCP/IP stack.
The SME is the core layer which manages the Wi-Fi connectivity. The SME
maintains the state machine to detect the activity on the Wi-Fi network and
indicates to the user accordingly. It also performs re-association to the
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