Digilent 410-302P-KIT - Manual (Page 8)

WiFire Reference Manual
6 802.11b/g Interface
The 802.11b/g compatible WiFi interface on the WiFire is provided by a Microchip MRF24WG0MA WiFi module.
This module provides the radio transceiver, antenna, and 802.11 compatible network firmware.
The MRF24WG0MA firmware provides the 802.11 network protocol software support. The DEIPcK and DEWFcK
libraries provide the TCP/IP network protocol support that works with the 802.11 protocol support provided by the
WiFi module.
The primary communications interface with the MRF24WG0MA WiFi module is a 4 wire SPI bus. This SPI bus uses
SPI4 in the PIC32 microcontroller, and this SPI controller is dedicated to use for communications with the WiFi
module
The WiFi module supports SPI clock speeds up to 25MHz. In addition to the SPI interface, the interface to the WiFi
module also includes a reset signal, an interrupt signal and a hibernate signal. The active low RESET signal is used
to reset the WiFi module. The external interrupt signal, INT, is used by the module to signal to the host
microcontroller that it needs servicing by the microcontroller software. The INT signal on the WiFi module is
connected to external interrupt INT4 on the PIC32 microcontroller and is not routed to any connector. The active
low HIBERNATE signal is used to power the WiFi module down and puts it into a low power state.
The interface signals to the WiFi module are controlled by the network libraries and are not normally accessed by
the user sketch. Refer to the schematic for the WiFire board for details on these connections.
More detailed information about the operation of the MRF24WG0MA can be obtained from the manufacturer
data sheet available from
www.microchip.com .
7 Network Library Software
The WiFi module on the WiFire is intended for use with the Digilent Embedded chipKIT network libraries, DEIPcK
and DEWFcK. The DEIPcK library provides TCP/UDP/IP protocol support for all chipKIT compatible network
interfaces supported by Digilent products, including the WiFire. The DEWFcK library provides the additional library
support required for connecting to and operating with the Microchip MRF24WG0MA wireless network modules.
Caution should be used in understanding that the DEIPcK library is different than the DNETcK network libraries.
DEIPcK is the Digilent Embedded Open Source IP stack that supports both the MX and MZ processor lines, while
the DNETcK IP stack is built on top of the Microchip MLA proprietary stack and only supports the MX processor
line, and will not work with the WiFire.
The DEWFcK library supports the MRF24WG0MA WiFi module as loaded on the WiFire. The correct header file
must be used to specify the network hardware being used by the sketch. When writing a network sketch on the
WiFire, use the following hardware library:
#include
The Digilent Embedded chipKIT network libraries are available for download from the Digilent website:
www.digilentinc.com/wifire .
There are reference examples demonstrating the use of these libraries in the library download.
Copyright Digilent, Inc. All rights reserved.
Other product and company names mentioned may be trademarks of their respective owners.
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