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Re: GPIO




----- Original Message -----
From: "Dave Matlock" <Dave.Matlock@xxxxxxx.com>
To: "dev-etrax" <dev-etrax@xxxxxxx.com>
Sent: den 3 november 2003 17:47
Subject: GPIO


> >From the code below (from
http://mhonarc.axis.se/dev-etrax/msg02558.html), how do I determine which
pins are going to be set?  How would I have determined that 0xffff << 8 is
referring to the 16 data pins on the parallel ports?

Chapter 20.9 in the designers reference:
http://developer.axis.com/doc/hardware/etrax100lx/des_ref/ET100LX_20_Electri
cal_Information_021107.pdf


> Also, is oe = 0x1 << 5 for enabling output on the parallel port?  Is this
unnecessary
> if the parallel port is disabled in the kernel?

Yes, you shouldn't need to control the oe pin unless you have
external drivers that are controlled by the oe pin.


Best regards
/Johan