Re: GPIO on consoleLCD-VX

> Hi,
>
>
> >     I got the LCD gum pack a while back and have been happily
> > playing about with it and picking up bits of info from this list. I
> > am however at a loss trying to work out how you interface to the
> > GPIO on the console LCD-vx.
> >
> > I'm not sure what I want to do but it's a learning experience so
> > if I could even connect a LED to the system and light it that
> > would be a start. Ideally I'd like to connect a temperature sensor
> > but perhaps I should forget the A/D stuff until I can light a led
> > and maybe "read" a switch state.
> >
> > This is a seriously basic question. I'm sorry I know this but I've
> > been searching and can't find any info. Maybe what I expected
> > is in error. I had expected as the consoleLCD-vx expansion has
> > GPIO listed in it's features I'd assumed that there'd be solder
> > points.
>
> So, pretty much every pin can be configured for some purpose or GPIO.
> So you need to find some pin whose functionality you're not using, and
> use it as a GPIO pin.
>
> Some likely candidates on the consoleLCD-vx are the audio (or AC97
> pins), and possibly the NSSP (SPI) pins.
> The AC97 pins are X_BIT_CLK, SDATA_IN, CLK32, SDATA_OUT, NACRESET,
> SYNC. The NSSP (SPI) pins are: X_MOSI, X_MISO, NSSPFRAME, and NSSPCLK.
>
> GPIO28 - X_BIT_CLK
> GPIO29 - SDATA_IN
> GPIO09 - CLK32
> GPIO30 - SDATA_OUT
> GPIO113 - NACRESET
> GPIO31 - SYNC
> GPIO13 - X_MOSI
> GPIO11 - X_MISO
> GPIO14 - NSSPFRAME
> GPIO19 - NSSPCLK
>
> I grabbed those from the consoleLCD-vx schematics. You can also find
> them on the motherboard I/O page.
>
> If you do:
>
> modprobe proc_gpio
> echo "GPIO out set" > /proc/gpio/GPIO31 will drive the SYNC line at 3.3v
> echo "GPIO out clear" > /proc/gpio/GPIO31 will drive the SYNC line to ground.
>
> So if you had an LED & current limiting resistor connected, one way
> would light it, and one way would extinguish it (which way does what
> depends on the exact wiring).
>
> Similarly, for input, you'd connect a pullup resistor between say
> CLK32 and 3.3v, and then connect a switch between CLK32 and ground.
> With the switch open:
> echo "GPIO in" > /proc/gpio/GPIO9 will configure CLK32 as a GPIO pin.
> cat /proc/gpio/GPIO9 will then show you whether the pin is set (3.3v)
> or clear (0v).
>
> --
> Dave Hylands
> Vancouver, BC, Canada
> http://www.DaveHylands.com/
>