===== Raspi Bit =====
A Raspberry Pi Zero board for the [[paper_bits:paper_bits_main|Paper-Bits]] to rule all GPIOs in Pure Data.\\
{{:paper_bits:pb205_raspi_bit_155332.jpg?600|}}\\
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==== Schematic ====
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==== change the PWM audio pins ====
[[https://www.raspberrypi.org/documentation/configuration/pin-configuration.md]]\\
[[https://www.raspberrypi.org/forums/viewtopic.php?f=91&t=86609]]\\
[[https://www.raspberrypi.org/forums/viewtopic.php?f=44&t=39138]]\\
Or like on [[https://othermod.com/raspberry-pi-zero-audio-circuit/]]\\
Open:
$ sudo nano /boot/config.txt
Add:
dtoverlay=pwm-2chan,pin=18,func=2,pin2=13,func2=4
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==== DAC ====
DAC0808: [[http://www.ti.com/lit/ds/symlink/dac0808.pdf]]\\
MC1408: [[http://pdf.datasheetcatalog.com/datasheet/philips/MC1408-8_3.pdf]]\\
Example: [[https://people.ece.cornell.edu/land/courses/ece4760/FinalProjects/s2003/gsh7/ECE476/archive.htm]]\\
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==== Negative Voltage Source ====
[[https://www.allaboutcircuits.com/projects/build-your-own-negative-voltage-generator/]]\\
[[http://www.stephenhobley.com/blog/2011/03/28/creating-a-negative-voltage-from-a-positive-one/]]\\
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==== Pure Data ====
**PD WiringPi:**\\
[[http://dernulleffekt.de/doku.php?id=puredata:gpio]]\\
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==== Links ====
[[https://learn.adafruit.com/introducing-the-raspberry-pi-zero/audio-outputs]]\\
[[https://othermod.com/raspberry-pi-zero-audio-circuit/]]\\
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