I just used my pigpio library.barkyj wrote: ...
Your method, I assume is not using the dt-blob ?
I am currently using the latest Kernel.
Where abouts are the edits you are talking about, made?
Yes.barkyj wrote:Hi Joan
Thanks for that.
Well ideally I want PWM out of one channel for Audio, and then to be able to control the PWM out of another channel to control a series of LED's, to vary their brightness (via a controller) from 0-100%.
So basically I am wanting to generate a PWM of approximately 130Hz, with duty from 0 to 100%, which is not affected by the Audio stream.
I hope that is enough information.
Is this something your library you are talking about, can do?
There are alternate SPI ports on gpios numbered higher than 31. That means you should be able to remap on the compute module (I think it allows physical access to the higher numbered gpios). You don't have any choice for the standard models (however the B+ does give access to SPI1 on gpios 16-21).Richard-TX wrote:I looked at the DTS code and do not see a definition for SPI. Can the SPI pins be moved as well?
Have you set the mode for gpio18 (ALT5)?jomag wrote:Hi. I have the same need: I want to connect a speaker directly to the GPIO header.
I have changed pin@p40 to pin@p18 in dt-blob.dts, compiled and installed it. I've verified that my changes was used as the left speaker stopped playing sound after changing this. I then restore pin 40 and did the same thing with pin 45, and then there was no sound on the right speaker.
But there is no output on GPIO18 while playing sound (pin 12 on the header)! I've verified this with an oscilloscope as well.
Any idea why one channel may work, but nothing on the other?
I'm testing on a new Raspberry Pi B+ with a clean installation of Raspbian 2015-05-05.
Nope. Is it necessary and how do I do that?joan wrote: Have you set the mode for gpio18 (ALT5)?
That's a handy tool, thank you.gsh wrote:...
You can check using the gpiostate tool:
apt-get install raspi-gpio
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