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by Burngate
Mon Jul 22, 2019 5:34 pm
Forum: Off topic discussion
Topic: big hands
Replies: 1
Views: 195

Re: big hands

Last time I went to collect my medication the pharmacist said I had beautiful hands. Be that as it may, they still won't fit where they need to be to undo that last PH00 screw. Putting "precision tools" into Google brings up a wealth of links - you might find some of them useful, though you can spen...
by Burngate
Mon Jul 22, 2019 5:17 pm
Forum: Troubleshooting
Topic: 1 of 6 Pis Not Booting
Replies: 5
Views: 142

Re: 1 of 6 Pis Not Booting

Have you a meter,and if so, is the 3v3 present? ... be gentle, its a Monday and theres only so much sarcasm my brain can handle :P Friday will feel better Monday mornin' feels so bad Ev'rybody seems to nag me Comin' Tuesday I feel better Even my old man looks good Wed'sday just don't go Thursday goe...
by Burngate
Mon Jul 22, 2019 10:44 am
Forum: RISCOS
Topic: How long will it take for Risc OS to be on todays level of Raspbian?
Replies: 28
Views: 678

Re: How long will it take for Risc OS to be on todays level of Raspbian?

jamesh wrote:
Mon Jul 22, 2019 8:00 am
rpdom wrote:
Mon Jul 22, 2019 7:32 am
DavidS wrote:
Sun Jul 21, 2019 9:56 pm
Cooperative Multitasking
Is that really a good thing?
No.
Other than in situations where it is.
In which case, yes.
by Burngate
Mon Jul 22, 2019 9:41 am
Forum: Beginners
Topic: Using Raspberry pie to teach AI
Replies: 2
Views: 77

Re: Using Raspberry pie to teach AI

"School children" can mean age 5 to age 15, so you may need to clarify this. "Artificial Intelligence" should mean rather more than what a small (i.e. desktop) computer is capable of, and anyway isn't necessary for recognising pictures, for example, so I assume you don't really mean it. Perhaps you ...
by Burngate
Mon Jul 22, 2019 9:28 am
Forum: Automation, sensing and robotics
Topic: Electret MIC MAX4466 with ADC ADS1015 in python with rasberrypi 3
Replies: 2
Views: 78

Re: Electret MIC MAX4466 with ADC ADS1015 in python with rasberrypi 3

It depends, of course, on how you've got everything wired, but ... The mic doesn't give out negative voltages, it gives out a signal centred on VCC/2, so if you're powering it from 3v3 you'll get values between 0v and 3v3. If the ADC is set to differential mode, it can give negative values, by compa...
by Burngate
Fri Jul 19, 2019 9:59 am
Forum: Automation, sensing and robotics
Topic: Project Idea getting feedback before I begin
Replies: 8
Views: 190

Re: Project Idea getting feedback before I begin

... I often have complaints of it not being answered or not answered within the 10 minutes we are supposed to answer it. ... Am I to understand you to be the member of nursing staff who would be answering, or are you more responsible for the call system itself? If the former, it may be worthwhile t...
by Burngate
Fri Jul 19, 2019 8:37 am
Forum: General discussion
Topic: Power Supply - Type C of Pi 4 model B
Replies: 32
Views: 1357

Re: Power Supply - Type C of Pi 4 model B

Imperf3kt wrote:
Fri Jul 19, 2019 8:00 am
... - power the Pi via the GPIO header, 5v pin/s and ground, or potentially the PoE header, if it can be leveraged for such use.
The PoE header doesn't carry 5v - it takes power from the ethernet socket and passes it to the PoE HAT, which then powers the Pi through the GPIO header.
by Burngate
Thu Jul 18, 2019 5:30 pm
Forum: General discussion
Topic: Raspberry Pi Zero W Power Abbilities
Replies: 5
Views: 287

Re: Raspberry Pi Zero W Power Abbilities

Read somewhere that an LED button can draw 25mA, and with 20 buttons that's 500mA. Plus the 150mA from the Pi I should be good to go. Thanks for the help. The current through an LED depends on how bright you want it, what colour it is (red ones have lower forward voltage than green ones, blue are h...
by Burngate
Tue Jul 16, 2019 9:33 am
Forum: General discussion
Topic: Pi 4 PCB Defect? (fiberglass thread loose)
Replies: 15
Views: 1000

Re: Pi 4 PCB Defect? (fiberglass thread loose)

From the description of what it actually is, I suspect a light touch with a fine file would clean it up nicely. I second this. ... Use of a mask is advised. The dust from the resin probably won't be a problem, but glass fibre dust isn't nice - it can get deep into the lungs and cause problems. Mayb...
by Burngate
Tue Jul 16, 2019 8:58 am
Forum: Graphics, sound and multimedia
Topic: How to send a sound signal through gpio pin to speaker?
Replies: 7
Views: 223

Re: How to send a sound signal through gpio pin to speaker?

I have a rpi 3 model b. ... cuz I’ve already got some stuff lying around. If building it from those isn’t recommended, what about a chip like the lm386? To a certain extent, it depends on how deep you want to go - do you want to buy a car, use some sheet steel and wheels and an engine you happen to...
by Burngate
Thu Jul 11, 2019 6:12 pm
Forum: Beginners
Topic: Voltage Sensors with Raspberry Pi
Replies: 2
Views: 92

Re: Voltage Sensors with Raspberry Pi

What is a "25V Voltage Detector Module 3-Terminal Sensor"?

And what sort of "generator"?
by Burngate
Thu Jul 11, 2019 5:47 pm
Forum: Advanced users
Topic: ESD protection diodes on the BCM2711
Replies: 8
Views: 338

Re: ESD protection diodes on the BCM2711

BlastFX wrote:
Thu Jul 11, 2019 3:44 pm
Guess I'll squeeze a proper level shifter in somehow.
A couple of resistors as a voltage divider should work on an input to the Pi, or a FET appropriately wired will work in both directions.
by Burngate
Thu Jul 11, 2019 10:41 am
Forum: C/C++
Topic: I dont get it... Why is everyone from science schools so obsessed with Perl and Python when we got C?
Replies: 303
Views: 6727

Re: I dont get it... Why is everyone from science schools so obsessed with Perl and Python when we got C?

Musketeer wrote:
Thu Jul 11, 2019 8:14 am
C is pure = it is simple! :twisted:
Is it?

Wouldn't it be better to go for assembler, rather than obfuscating everything with a high-level language?
That way, the student will learn what's actually happening.
by Burngate
Thu Jul 11, 2019 9:28 am
Forum: Beginners
Topic: [SOLVED] Can I connect an arduino directly to GPIO using a 10k ohm resistor?
Replies: 9
Views: 216

Re: How to change a title

ZXY007o0ePksrW7L wrote:
Wed Jul 10, 2019 9:15 pm
If this forum supports it and I can figure out how, I'm going to mark this as solved.
Just go to your first post, edit it and change the title - just like I've just done for this post!
by Burngate
Thu Jul 11, 2019 9:03 am
Forum: Advanced users
Topic: ESD protection diodes on the BCM2711
Replies: 8
Views: 338

Re: ESD protection diodes on the BCM2711

Unless it's significantly different from previous SoCs, it doesn't have protection diodes as such - merely parasitic elements that sort of work as clamp diodes, and if significant current passes through one, it's likely to cause latchup and damage the silicon. http://www.mosaic-industries.com/embedd...
by Burngate
Thu Jul 11, 2019 8:47 am
Forum: General discussion
Topic: Charger compatibility with the Pi 4 (Single Type C CC resistor on Pi4)
Replies: 28
Views: 3149

Re: Charger compatibility with the Pi 4 (Single Type C CC resistor on Pi4)

Or a Mondeo engine in a Volvo. Have you done that then? My next-door neighbour runs a repair shop, so when my 10-year-old V70 decided to not even try to start, I asked him for help, and that's what he told me. He also told me the fault wasn't with the engine, or the battery, or the over-complicated...
by Burngate
Wed Jul 10, 2019 5:45 pm
Forum: General discussion
Topic: Charger compatibility with the Pi 4 (Single Type C CC resistor on Pi4)
Replies: 28
Views: 3149

Re: Charger compatibility with the Pi 4 (Single Type C CC resistor on Pi4)

Almost as bad as putting an EEPROM on a Pi.

Or a Mondeo engine in a Volvo.
by Burngate
Tue Jul 09, 2019 6:21 pm
Forum: General discussion
Topic: Micro/type-c USB power supplies immunity to backpowering validity/proof
Replies: 13
Views: 688

Re: Micro/type-c USB power supplies immunity to backpowering validity/proof

If you have been unable to find a USB specification that requires a diode, then assume it's not in the spec. And I agree - manufacturers are quite likely to cut costs where they can. If you're worried, then put your own ideal diode on your board - better safe than sorry, and also cheaper than a lawy...
by Burngate
Tue Jul 09, 2019 5:10 pm
Forum: General discussion
Topic: Micro/type-c USB power supplies immunity to backpowering validity/proof
Replies: 13
Views: 688

Re: Micro/type-c USB power supplies immunity to backpowering validity/proof

I'm not sure I understand - are you designing (for sale) a power supply, or a device that needs a power supply? If you're designing a power supply, then it seems obvious - make sure it won't sink current if another supply is connected to it, by building in an ideal diode or by any other means you wi...
by Burngate
Tue Jul 09, 2019 9:50 am
Forum: General discussion
Topic: Micro/type-c USB power supplies immunity to backpowering validity/proof
Replies: 13
Views: 688

Re: Micro/type-c USB power supplies immunity to backpowering validity/proof

In full, the paragraph reads: NOTE that the Raspberry Pi 3B+ and Pi Zero and ZeroW do not include an input ZVD. The micro-USB input on a Pi is expected to / almost universally is driven by a power source which does not sink current, i.e. it will not try to actively pull down a voltage higher than it...
by Burngate
Mon Jul 08, 2019 5:47 pm
Forum: RISCOS
Topic: RISC OS Pi?
Replies: 30
Views: 1078

Re: RISC OS Pi?

... Though reasons one may consider RISC OS include: It is different. Now there is the downside that it is a good bit different to use than other OS's. I tend to see things slightly differently - RISC OS is what I grew up with, so it's all the other OS's that are different. It seems there are a spe...
by Burngate
Sun Jul 07, 2019 9:45 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Pi 1B: Deactivate all LEDs
Replies: 5
Views: 267

Re: Pi 1B: Deactivate all LEDs

I would like to deactivate all LEDs (but ACT = cpu0) of a Pi 1B at startup. Any Ideas how to deactivate the PWR-LED? "/sys/class/leds/led1" does not exist. led0 works fine. If it's really an early Pi - from round 2013 - then you can't. The PWR LED is directly wired to the 3v3 line. From the B+ to 3...
by Burngate
Fri Jun 21, 2019 9:43 am
Forum: Troubleshooting
Topic: Wrong Image Color
Replies: 13
Views: 841

Re: Wrong Image Color

Rupiert wrote:
Fri Jun 21, 2019 6:31 am
So: I have 6 Rpi's (half zero pi's) there all have the same cam.
Do you mean you have only one camera that you swap between the six Pis, or do you have six supposedly identical cameras, one for each Pi?
by Burngate
Fri Jun 21, 2019 9:30 am
Forum: Beginners
Topic: How to turn on a LED
Replies: 8
Views: 936

Re: How to turn on a LED

Any chance you can explain how did you know this board had a split? Is it because the red / blue lines break around row 30? That break in the red and blue lines is certainly a clue, but mainly it's just experience. Most of us have already made the same mistake, some of us several times. The same go...
by Burngate
Tue Jun 18, 2019 5:48 pm
Forum: Off topic discussion
Topic: [FIXED] Ego Search / Own Posts failing
Replies: 59
Views: 9811

Re: [FIXED] Ego Search / Own Posts failing

Depending on your browser, there is a way of fixing the width problem with the forums. I use it with Firefox and it goes full screen width for me no matter which screen I'm using. I have to admit I've not managed to find anything in Firefox like that. It's possible that an update to Firefox disable...

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