From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 In-Reply-To: <20140508183622.E368BB827@mail.bitblocks.com> References: <275c3465707d98d4c1f88f81b40670fd@quintile.net> <20140508183622.E368BB827@mail.bitblocks.com> From: Krystian Lewandowski Date: Fri, 9 May 2014 16:11:00 +0200 Message-ID: To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: multipart/alternative; boundary=001a11c258dc00a47704f8f82c3d Subject: Re: [9fans] radio Topicbox-Message-UUID: e4bb079a-ead8-11e9-9d60-3106f5b1d025 --001a11c258dc00a47704f8f82c3d Content-Type: text/plain; charset=UTF-8 I was working on GPIO under Plan9 - very simple thing but also supports edge-raising/falling events. I had simple C code to print what pin triggered an event. I'll try to push this simple test to github during weekend. Though i'm not sure how it can be integrated - is events counting enough? Krystian https://github.com/elewarr/plan9-bcm 2014-05-08 20:36 GMT+02:00 Bakul Shah : > On Thu, 08 May 2014 18:58:31 BST "Steve Simon" wrote: > > I have a hifiberry (http://www.hifiberry.com/) nicely minimalist, > > though no driver at present - I will await the GSOC project :-) > > > I have some itron VFDs from work, 256 x 64 pixel. I like these as > > the visibility is excellent. The only annoyance is they have > > a parallel interface and I use up all the PI's GPIOs. > > > I also need to interface a rotary encoder for the tuning knob which > > is also a pain - not complex enough to justify an FPGA, but a bit too > > much to poll when the PI is doing audio decode as well. > > No need for polling. The BCM2835 can handle edge triggered > interrupts. Or you can use a PAL or CPLD. > > > Thinking of adding a PIC or an AVR just for the encoder / VFD interface > > and talking i2c to it. > > --001a11c258dc00a47704f8f82c3d Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
I was working on GPIO under Plan9 - very simple thing but = also supports edge-raising/falling events. I had simple C code to print wha= t pin triggered an event. I'll try to push this simple test to github d= uring weekend. Though i'm not sure how it can be integrated - is events= =C2=A0counting enough?

Krystian

2014-05-08 20:36 GMT+02:00 Bakul Shah = <bakul@bitblock= s.com>:
On Thu, 08 May 2014 18:58:31 BST "Ste= ve Simon" <steve@quintile.net= > wrote:
> I have a hifiberry (http://www.hifiberry.com/) nicely minimalist,
> though no driver at present - I will await the GSOC project :-)

> I have some itron VFDs from work, 256 x 64 pixel. I like these as
> the visibility is excellent. The only annoyance is they have
> a parallel interface and I use up all the PI's GPIOs.

> I also need to interface a rotary encoder for the tuning knob which > is also a pain - not complex enough to justify an FPGA, but a bit too<= br> > much to poll when the PI is doing audio decode as well.

No need for polling. =C2=A0The BCM2835 can handle edge triggered
interrupts. =C2=A0Or you can use a PAL or CPLD.

> Thinking of adding a PIC or an AVR just for the encoder / VFD interfac= e
> and talking i2c to it.


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