<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:'times new roman', 'new york', times, serif;font-size:12pt"><div>Hello everyone,</div><div><br></div><div>I am trying to emulate an SPI interface using four GPIO pins. This is a desktop computer with linux 2.6.28 kernel.</div><div><br></div><div>The problem is I don't know if the pins are working. I read that if I have the sysfs support for the kernel (which I do :D) all I have to do</div><div>is enable the respectiv pin using </div><div><br></div><div>echo N > /sys/class/gpio/export</div><div><br></div><div>And I would get a gpioN directory </div><div><br></div><div>But I always get: "write error : invalid argument."</div><div><br></div><div>Is there some other option i need to enable first? The people I am working with assured me that these pins are not used by any other device and they haven't found anything to suggest that they were
turned off manualy.</div><div><br></div><div>Please help,</div><div><br></div><div><br></div><div style="position:fixed"></div>
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