General - Pisound Documentation

Pisound
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Dedicated topic for General - Pisound Documentation page.
This is a companion discussion topic for the original entry at https://blokas.io/pisound/docs/general-specifications
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Hello. would like to be sure before soldering the 2x8 pin header on the top of the pisound.
you provided a pinout of the pisound header which i measured and i found
pin2=5.1V, pin4=3.3v, pin6=3.1v, pin8=0v, pin10=3.10v, pin12=0v, pin14 =3.3v

pin3=3.3v, pin5 =3.10v, pin7=0v, pin9=0V, pin11=3.10V, pin13=3.30v

since i’m a bit new here, for pin 3 and 10to14 i’m not sure… but as far as i see , at least pin 5, 6, 7, 8, 9 are general io therefoer they should have 0v when not used isn’'it?
why i get those voltages on pin 5, 6?
in a script, if i GPIO.setup(18, GPIO.OUT) , it means i’m actually using pisound header pin n.5 as an output?
thanks

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Hi, the GPIO pins on the 2x7 header use the default configuration by Raspberry Pi - Pisound does not modify it in any way.

The reason why you’re getting these readings is that the pins are by default configured as inputs, and some pins by default have pull-up or pull-down enabled. See:

Raspberry Pi Documentation - Raspberry Pi hardware, section " Power-on states" and the alternate function table in the ARM peripherals datasheet, section 5.3, column ‘Pull’

Pin 5 pin is BCM5, connected to Pin 29 of the RPi header.

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Hello, just to make sure before I connect stuff and start soldering.
… and maybe I’ve overlooked something, and in that case, this is a very dumb question … :slight_smile:

PiSound header, pin number 6 (of the 2x7 pins), is stated as BCM 6, that’s Raspberry Pi’s GPIO 6 , physical pin number 31 (on the Raspberry Pi header).

But the diagram above shows pin 31 as Red - “Pins used by Pisound”

So now I am confused, can I use GPIO 6 or not?

Also, can I use GPIO 9, 10 and 11 as SPI0 pins (MISO, MOSI and SCLK)?
(to drive SPI peripherals with SPI0 CE1 / GPIO pin 7)

BCM 7/ SPI0 CE1 is available on the 2x7 header, but the other SPI0 pins MISO, MOSI and SCLK are not, so I will use the standard 40 pins header for that, using one of these (GPIO Edge Connector)

Thanks!

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It’s a mistake in the image, GPIO 6 is available for your use. I’ve verified the rest of the pins, they are correct. Thank you for bringing this to our attention.

Yes, you may use the SPI with CE other than 0.

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