Nakedible
  • Member for 9 years, 4 months
  • Last seen more than 4 years ago
  • Helsinki, Finland
What SPI frequencies does Raspberry Pi support?
30 votes

The Raspberry Pi SPI runs at APB clock speed, which is equivalent to core clock speed, 250 MHz. This can be divided by any even number from 2 to 65536 for the desired speed. The datasheet specifies ...

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Can Raspberry Pi reliably bit bang a 9600 baud serial and is there example code?
Accepted answer
15 votes

I finally solved this, but in a pretty unorthodox way. I abandoned bit-banging as too unreliable and tried to find other solutions which would allow me to the same thing without adding more hardware. ...

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How much power can be provided through USB?
14 votes

Just noting that the rev 2.0 board no longer has the USB polyfuses, just the input 1.1A polyfuse. So the issues mentioned here should no longer be present in current generation Raspberry Pi boards. ...

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Which CPU flags are suitable for gcc on Raspberry Pi?
11 votes

This depends on what libraries you wish to link your code with. If you are using the Raspbian images, the architecture is "armhf" and the compilation flags are: -march=armv6 -mfpu=vfp -mfloat-abi=...

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Can Raspberry Pi reliably bit bang a 9600 baud serial and is there example code?
10 votes

It would seem that atleast without the real-time patches (CONFIG_PREEMPT_RT), the Raspberry Pi cannot reliably bit-bang a 9600 baud serial. I used a simple latency tester which configured all the ...

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How do I wait for interrupts in different languages?
Accepted answer
6 votes

In general, you cannot access interrupts directly from a userland program. Those interrupts need to be exposed via some kernel facility to do what you want. The kernel exports gpio devices as /sys/...

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What are the different clock sources for the general-purpose clocks?
Accepted answer
5 votes

Although it is not specified explicitly, I assumed from the spec that: PLLA = 650 MHz PLLB = 400 MHz PLLC = 200 MHz From this, I would suggest the following: SRC = 4 (PLLA), MASH = 1, DIVI = 57, ...

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Disable screen blanking in X-Windows on Raspbian
3 votes

As it was clarified in a comment that the commands work while being run from a terminal, but not from .xinitrc, and that Chromium is being started from .config/autostart/, I would suggest the ...

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Get High Quality Audio from HDMI
1 votes

HDMI transfers digital audio, while your stereo RCA audio inputs require analog audio. A simple cable will not do it. There are many HDMI splitters which allow you to separate the digital audio from ...

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