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GA1000 is an add-on Wi-Fi module implementing 802.11b/g protocols (for documentation see Programmable Hardware Manual). This add-on device cannot work by itself and requires "external brains" in the form of one of Tibbo devices.
The GA1000 communicates with Tibbo devices through an SPI interface. Your device will control the GA1000 through five GPIO lines:
Providing hardware reset
The wln. object directly controls CS, CLK, DI, and DO lines. Your application, however, must take care of the proper hardware reset for the GA1000. There are two methods for doing this:
Tibbo devices differ in whether the CS, CLK, DI, and DO lines are remappable. On devices with remappable lines, you can choose any set of GPIOs to control the GA1000. On devices where remapping isn't provided, you just have to use "prescribed" GPIO lines. For information on this, see Miscellaneous information section of your platform's documentation (for example, EM1000W's is here).
Special case — the EM500
Diagram C shows the recommended way of connecting the GA1000 to the EM500 module. GPIO lines are a precious commodity on the EM500 — there are only eight of them available. As seen on the diagram C, you can get away with using only three lines to control the GA1000 (against the standard five lines). One line is saved by producing the reset out of CS and CLK lines. The second line is saved because EM500's bidirectional GPIOs allow interconnecting DI and DO. The EM500 does not allow remapping of GA1000 lines, so GPIO line assignment shown below cannot be changed.