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12 votes

Raspberry Pi DPI only works over short distances. Why?

All cables have a length limit. When you exceed that length limit, the signals in the cable attenuate due to resistance of the cable, get deformed due to capacitance and inductance in the cable, and ...
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5 votes

Raspberry Pi DPI only works over short distances. Why?

Your Hyperpixel has a resolution of 800 x 480 x 60fps, so the data rate is 23,040,000 pixels per second, plus some gaps for synchronisation. You can't send such a fast signal over an arbitrarily long ...
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3 votes
Accepted

AttributeError: module 'RPi.GPIO' has no attribute 'ChangeDutyCycle'

Those functions are part of GPIO.PWM. Instead of motor_1_f = GPIO try motor_1_f = GPIO.PWM(channel, frequency)
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  • 46
2 votes
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How to install wiringpi on Raspbian

The question shows different architectures armhf vs. arm64 for the packages. dpkg: dependency problems prevent configuration of wiringpi:armhf: wiringpi:armhf depends on libc6. ^^^^^ ...
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  • 138
2 votes

How to install wiringpi on Raspbian

EDIT: wiringpi is now in the apt ports repo; so: sudo apt install wiringpi Contrary to some opinions, wiringpi is not a waste of time for everyone. And as long as we are expressing opinions, here's ...
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2 votes

My relay triggers on access. How to disable this?

"Normally open" contacts are open when there's 0V on the relay coil. Depending on the circuit of the module, that could correspond to 0V or 5V on the digital input which you connect to the ...
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2 votes

Raspberry Pi DPI only works over short distances. Why?

Think about what else is connected to your Pi which should be 3.5m away from the screen. Are those USB devices? Some I2C sensors? A power supply? It could be that your best option is to keep the ...
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2 votes

Simple float switch sensor frying GPIO pins, while the other doesn't? Hydroponics system

You likely have another power supply in your system (for the pumps, etc.) and it's likely much higher voltage than 3.3V. You need to make sure there's no way for the current to go from this power ...
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2 votes
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Simple float switch sensor frying GPIO pins, while the other doesn't? Hydroponics system

This is not really a Pi question. You are ignoring most of the environment - what else is connected; I assume the solution is connected to some kind of pump and is conductive - this is almost ...
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1 vote

Simple float switch sensor frying GPIO pins, while the other doesn't? Hydroponics system

I will take a SWAG: You have no protection on the GPIO pins which is bad especially with the long wires connected to them. The leds are close to the motor power leds which are great radiators of ...
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  • 707
1 vote

Arming an AreoStar ESC with Raspberry Pi to manage brushless motors

When arming the ESC it is looking for the upper and lower values to set the range. For some reason setting the lower range to 0 (where it sends no signal) was not acceptable. Therefore the following ...
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  • 109
1 vote

Raspberry PI noise reduction on analogue sensors

Don't try to get to the perfect solution in one step. Instead, build a simple prototype that works and check how good your measurements are. There's a chance you don't need a separate voltage ...
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1 vote

Raspberry PI noise reduction on analogue sensors

You have specified insufficient information e.g. sensor specifications, distance (or evidence of a problem) for any meaningful answer. This is NOT a Pi specific question as the solution would be the ...
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1 vote

Raspberry Pi DPI only works over short distances. Why?

The bottom line is that DPI was simply not designed for those kinds of distances. It might be possible to stretch it out by building something like a custom cable with individually screened wires (or ...
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