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Re: general purpose driver




----- Original Message -----
From: <u9900545@xxxxxxx.fi>
To: <dev-etrax@xxxxxxx.com>
Sent: den 30 oktober 2002 14:03
Subject: general purpose driver


> Hello!
> We are planning to use ETRAX LX100 PCB for general purpose DAQ. The plan
> now is to connect 16-bit I/O interface to LPT port. Has anybody written
> general purpose driver for I/O to achieve better performance in speed? Or
> do you have better ideas?
>
> Sami Vuolab
>

What functionality do you need?
What are your speed requirements?
Is it individual bits or do you want to send

The gpio driver supports port G so if you need access to individual bits
that could be used.
The new version in our 2.4.19 patch support setting "alarms" using ioctl()
to tell the driver to check when some bits go high or low,
the usermode application can do select() on the gpio fd and wake up
when something has happened instead of polling the kernel.

The gpio driver also supports clocking data out, although it currently
only supports that on PA and PB I think.
You first do a ioctl() to configure what bits to use for what
and can then do a write() to send data - we used that to program a FPGA.

Best regards
/Johan