How do I create a clock?

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1

How do I create a clock?

I was use vi editer (user space)

GPIO_HIGH();
GPIO_LOW(); ← SO I has used but it is very slow …

So, i want to create clock in BBB

How do I create a CPU clock?

2

which type of clock?

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Well, this question is a bit like asking “How do I make a car?”

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Sorry Sorry …

I am doing a project using the camera.

but ,The first method is to receive data rate is too slow.

GPIO_HIGH();
GPIO_LOW(); ← Userspace coding

So ,I hope come to read the data a little more quickly.

can someone help me?

2015년 7월 27일 월요일 오전 6시 55분 21초 UTC+9, William Hermans 님의 말:

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Video4linux?

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Use PRU to read/write I/O pins which can be done in 5ns. I don’t understand how you want read data through GPIO pins from a camera.

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thanks for reply

Put the clock in the camera comes out give data.(8bit)

So I made read clk and recived data.

However, the speed of reading data from a GPIO through the mmap was slow to solve the problem, but a problem occurred a slow in clock speed makes the BeagleBoard

So I have such a question.

2015년 7월 28일 화요일 오전 3시 43분 44초 UTC+9, Karteek YV 님의 말:

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If you control a GPIO pin from a high level language via the linux-system-file-io, you can toggle the pin at about 6 kHz maximum.

If you control a GPIO pin directly from a language like “C”, you can toggle it at about 4 MHz, maximum.

If you control a GPIO pin from the PRU, you can toggle it at about 200 MHz maximum.

In each case, maximum is a simple program that just says HI, LOW, HI LOW, HI, LOW, etc.

Any additional program, will slow it down, some.

— Graham