Raspberry Pi Forums

drgeoff

jamesh wrote: ↑
Thu Apr 16, 2020 7:57 am
If there was documentation, it wouldn't be discrete!

There could be a discreet release of discrete documentation.

("discrete" != "discreet")

drgeoff

mannok wrote: ↑
Wed Apr 15, 2020 11:36 am
But the Battery can supple only 1A at max, which mean it may not work properly?

I was updating my post while you wrote that. See aboove.

drgeoff

Let say I have non-inductive Load and it is rated as follow: 0.2A @ 1V applied 2A @ 5V applied Which is powered by a DC battery and is rated as follow: 5V output 1A max current supply I am going to divide the supply voltage by switching it with PWM, say 20% duty cycle and as a result we can simulat...

drgeoff

gloryhound11 wrote: ↑
Tue Apr 14, 2020 9:51 pm
Is it possible to connect 2 pi 4s to each other to effectively double the graphical and computing power?

If you bolt two cars together, you can carry more passengers but will it go faster?

drgeoff

If you have mistyped that second number and it actually has four 2s, then it is a 2N2222 or 2N2222A equivalent.

I suspect the 644 is on a different line and is a date code or factory code, not part of the part number.

drgeoff

Read the "not booting" sticky.

drgeoff

For Eben Upton's view in 2012 on open sourcing the RPi hardware watch http://www.youtube.com/watch?v=QXLShQH__6M

(It is only 66 seconds long.)

drgeoff

Without using two identical capsules sited very close together you are not going to have much success with good cancelling over a range of frequencies. Waves sound very much like noise which does cover a wide spectrum. Stick to one microphone. The usual technique to record bird song is to mount a mi...

drgeoff

There is a difference between a product which will initially sell in small numbers but has the potential to sell in large numbers given the right circumstances and a product which will always be in a small niche market.

drgeoff

klricks wrote: ↑
Mon Apr 13, 2020 3:29 pm
Have you tried the expand filesystem option?
Code: Select all
sudo raspi-config
Advanced Options menu A1.

That was already asked and answered in the original thread which mahjongg unwisely (IMHO) decided to split this one off from. viewtopic.php?f=63&t=270724

drgeoff

- How to you connect your arduino to the PI? Via an USB adapter or directly to one of the TTL serial on the GPIO. - What type of Arduino ? is it a 3.3V or 5V version? if it is a 5V version, do you have any type of signal converter to swicth 5V signal to 3.3V? If you use a 5V arduino directly on the...

drgeoff

What serial to TTL adapter and how are you powering it? Strictly speaking TTL logic levels are 0 and 5 volts whereas RPi GPIO (including the serial ones) use 0 and 3.3 volts and are NOT 5 volt tolerant. Applying 5 volt signals can damage the GPIO and even cause eventual death of the complete SoC.

drgeoff

pcmanbob wrote: ↑
Mon Apr 13, 2020 9:53 am
Looking at the specifications of the second buzzer this on works at voltages 3-24V DC at 12mA so you still can drive it from a gpio pin

But only if you have its wires the correct way around.

drgeoff

If the ssh and wpa_supplicant files are still present after powering up, the RPi has not booted successfully. The 169.254. address signifies that the RPi has not recieved an IP address from the router. Possible reason is failure to establish the Wi-Fi connection. The COPAL response is from something...

drgeoff

Is it ok to connect a raspberry pi zero w to a pc with a usb cable (for ethernet over usb) while it is being powered through its micro usb power port? I am afraid of frying something. It isn't a good idea. A PC USB port should be easily be able to provide enough power for a ZeroW. If you need extra...

drgeoff

The flat flex cable on the RPi camera and the RPI screen are inserted into the respective dedicated sockets for them on the RPi board. The Zeros (all versions) do not have the display socket. The Zeros have a smaller camera socket than other RPis and require a different cable.

drgeoff

And on the raspberry dont i need a hifi dac sound car?? Or a external usb sound card? Depending on the sort of audio you will be listening to, the condition of your auditory system, the noise level in your car when listening and such factors you may find that the quality available from the analogue...

drgeoff

@LTolledo

That old "i before e" thing also applies to "ingenuity".

drgeoff

alphanumeric wrote: ↑
Thu Apr 09, 2020 7:50 pm
You could see if it will Boot from USB. Card slot wouldn't be needed if it works.

How?

A 3B needs to have an OTP bit set to enable boot from USB. That can only be done once it has booted. From a card in the card slot.

drgeoff

That happens when the RPi does not connect to the WI-Fi router. You need to troubleshoot that. Maybe marginal Wi-Fi signal level.

drgeoff

sudo dd bs=4M if=/dev/mmcblk0 of=/media /user/Raspbian.img But it has the problem that it generates a very large copy: MicroSD 32GB generates a 30GB file But the MicroSD only has 5GB used, why does it generate a 30GB file? That command makes a byte by byte copy of the whole card. It takes no accoun...

drgeoff

jbudd wrote: ↑
Wed Apr 08, 2020 1:47 pm
I think you may have got hold of a card with an old version of NOOBS which doesn't work on the Pi 4B.

I think that is not a plausible explanation given that the files on the card include bcm2711-rpi-4-b.dtb

drgeoff

There are HDMI to VGA cables that rely on the HDMI device being able to put into a mode where it outputs VGA signals from its HDMI socket. No RPi can do that so such cables will never work. An adaptor containing active electronics is required to connect the HDMI ouput of a RPi to a VGA only display.

drgeoff

Basically it seems the camera can't be seen by the Raspberry Pi 4 when connected directly using an ethernet cable. What do you mean by "seen"? There are two separate issues: 1. The data link between camera and RPi. fotl has commented on that. 2, The software on the RPi that does something with the ...

drgeoff

All beginners are not beginning at the same point. Nor do they have the same idea of where they want to get to.

Search found 10817 matches

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