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Search - "5v"
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windows update code
function update(){
print("10%");
print("30%");
print("50%");
print("99%");
_doActualUpdate();
_mineBitcoin();
print("100%");
return;
}15 -
Googles best javascript framework.
1st link: react is the best one.
Me: Ignore
2nd link: Angular is the best one.
Me: ignore.
.
.
.
8th link: Vue is the best one.
Me: I knew it.18 -
Long rant ahead. Should take about 2-3 minutes to read. So feel free to refill your cup of coffee and take a seat :)
It turns out that the battery in my new Nexus 6P is almost dead. Well not that I didn't expect that, the seller even explicitly put that in the product page. But it got me thinking.. why? Lithium batteries are often good for some 10k charges, meaning that they could last almost 30 years when charged every day! They'd outlive an entire generation of people!
Then I took a look at the USB-C wall charger that Huawei delivered with this thing. A 5V 3A brick. When I saw that, I immediately realized.. aah, that's why this battery crapped out after a mere 2 years.
See, while batteries are often advertised as capable of several amps (like 7A with my LiitoKala 18650 batteries that I often use in projects), that's only the current that they can safely take or deliver without blowing up. The manufacturer doesn't make this current rating with longevity in mind. It's the absolute maximum in current that a given battery can safely handle.
The longevity on the other hand directly depends on the demand that's placed on the battery. 500mA which is standard USB 2.0 rating or 1A which is standard USB 3.0 rating, no sweat. The battery will live for at least a decade of daily charges and discharges like that no problem.
But when you start shoving 3A continuous into a battery, that's when it will suffer. Imagine that your current workload is 500mA and suddenly you get shoved 6 times that work upon you. How long would you last?
Oh and not only the current is a problem, I suspect that it also overvolts the battery to maintain a constant current all the way till the end. When I charged my lithium cells with my lab bench power supply, the battery would only take a few milliamps when it got close to the supply voltage. Quick bit of knowledge: lithium cells are charged at constant current first, then when the current drops below that, it continues at constant voltage - usually 4.2 or 4.35V depending on the battery. So you'd set your lab bench power supply at 4.2V 500mA. But in that constant voltage mode, as the battery's voltage and the supply's voltage equalize, the current drops because the voltage difference becomes lower. Remember, voltage is what causes current to flow. Overvolting at the supply to stay in constant current mode all the way till the end speeds this process up but can be dangerous and requires constant monitoring of the battery voltage.
So, why does Huawei and a bunch of other manufacturers make these 3A power chargers? Well first it's because consumer demands ever more, regardless of the fact that they can just charge at 500mA for the night (8h of sleep) and charge a 4000mAh battery from 0 to 100% no problem. Secondly it's because sometimes you need that little bit of extra juice fast, like when you forgot to plug the damn thing in and you've got only 30 minutes in the morning to pour some charge into it.
But people use those damn fucking things even when they go to bed, making that 3A torture a fucking standard process!! And then they complain that their batteries go to shit?!
Hopefully this now made you realize that the fast charger shouldn't be used as a regular charger ^^29 -
Project manager: I thought you said you made sure it was live today! I'm going to have to explain that you're the main issue with why it isn't live to management!
Me: have you cleared your cache?.... (long silence)
I swear it's the new "have you tried turning it off and then on again".2 -
Meme intended for physics, but sometimes it also happens in progamming. I am looking at you Javascript.
Source: https://theladyscientist.tumblr.com/...4 -
The best minds of my generation are thinking about how to make people click ads…That sucks.
- Jeffrey Hammerbacher, former Facebook engineer1 -
Lol 😂. I was expecting a mnemonic of some kind but this works too.
https://stackoverflow.com/questions...2 -
Once I used to wonder how youtube made money.
Now every time I watch a youtube video I am reminded how.12 -
Today is finally the day of my hackathon, have been working with my team for about a month on a personal assistant already. I think we may stand a chance to get in the finals this year, unlike last year, when we started working only on the day of the hackathon.3
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Submitting long written text on browser.
Novice:
1. Type
2. Submit
Experienced:
1. Type
2. Ctrl+a Ctrl+c
3. Submit4 -
Yet another rant about crappy electronic designs.
Just now I was cleaning my desk and stumbled upon some old hard drive in a caddy that I still had laying around.. I figured, let's plug it in and see whether the drive still works. And to some extent, it does! Except that every few minutes it craps out on me. And after disassembling the caddy, I think that I know why.
Just as background information, hard drives work at 12V and generally require about 10W to spin their motor. Meanwhile USB operates at 5V. So a boost converter needs to be present in the controller to step up the voltage and power the drive.
Now what's a boost converter? It's an inductor, a capacitor, a transistor and a diode in a specific arrangement (if you're interested in the design, check out https://youtube.com/watch/...), along with feedback circuitry to stabilize output voltage. Now that transistor is important.. it switches at very high frequency, and its rise and fall times create heat. In the particular transistor used in that controller, it apparently causes the transistor to operate at 65-68°C. That's quite toasty IMO, and overheating may be why the controller is so unstable. But the Chinese manufacturers thought that it's just fine and okay to be sold without heatsink or some research into transistors with better rise and fall times.
So the hard drive craps out on me and yet again it's because of certified shitdesigns. MOTHERFUCKTURERS!!!!27 -
My friend brought me a simple python problem. He expected the output to be 2,2,3... instead of 2,3... I didn't know python, but with a quick tweak to differentiate the two prints, I understood that the range() function is exclusive.
Before coming to me, he asked his senior dev & that guy just said - "Oh, your editor has a problem". 😐5 -
draw.io is moving to diagrams.net, because .io domains are not secure.
Source: https://diagrams.net/blog/...12 -
TL;DR: check polarity before plugging your DIY circuits into others!!!
*goes off to watch some Lucky Star and drink some booze*
*notices phone battery dying after 3rd pint*
But my charging cable that Huawei delivered with this thing is way too short... Well that ain't no problem, I can make one of my own 😎
But I'm tipsy.. sound I really enter the workbench in this state?
*goes off to build a charging cable anyway*
But what was USB-A male connector's polarity again? Oh, there's the fan's USB connector that I've made in the past. Let's check on that one. So, left is positive and right is negative?
*solders the wires on*
Snip, strip, stick, done! Well that was easy. I guess that all those failed soldering attempts and lost pads in the past as a means of training did pay off in the end!
*plugs phone into Raspberry Pi media center through new charging cable*
Strange sounds coming from the speakers.. well that's odd. Reverse polarity or maybe the Pi can't handle a 1A load from my phone?
*plugs phone into the 5V 5A charging hub that I've made earlier*
That oughta do.. current limits should be no more in that thing.
*charging hub makes high-pitch noise similar to the Pi speakers*
Definitely a reverse polarity, isn't it :') let's check on the Gargler...
Oh shit! It is a reverse polarity mistake!!! Should've checked this earlier >_<
*resolders wires properly*
Alright, finally done.. as I'm writing this post, my phone's charging from the Raspberry Pi through my fixed charging cable now...
Lesson learned. Always check on the internet what the pinout is before soldering anything, don't solder while tipsy, and be fucking grateful that this phone has reverse polarity protection in it.
Nexus 6P with all its shortcomings regarding power delivery and battery management, luckily it's got reverse voltage protection features built-in. Otherwise it might've costed me my phone. Always double-check before plugging anything into something else!!!5 -
Finished an MVP of my garage-opener-thingamajig!
Basically I decided I wanted to control my garage from my app. Retail solutions are expensive af. As a dev, the choice was easy!
RPI3
HC-SR04 sensor
DHT temperature sensor
5v Relay
Nativescript + Angular
Firebase
Result: i can open my garage anywhere, safely (sorta?) via firebase, and get push notifs when it gets opened (from hcsr04), which triggers the pi camera, while also getting live temp feeds (this one is kinda for the giggles and utterly pointless but NUMBERZ!)
Anyway - fun side project! First version of my app looks like this. Its very rough, and I have a couple more details I wanna display, but for a first time app I'm happy!10 -
"First remove the break points, and then commit the code".
He described it as if the breakpoints could stop time!! 😂5 -
After seeing @Gregozor2121 share, I searched around in my bookmarks for similar stuff. Here are a couple of links that I feel is useful for everyone:
A massive list of Free programming books.
https://ebookfoundation.github.io/f...
(Also do explore anything marked as "awesome", cause it literally is awesome!! They have got tons of lists of resources for most programming languages, free software lists, famous stackoverflow answers, quotes & even Pokemon!!)
I also had this bookmarked:
https://github.com/chubin/cheat.sh
Basically cheat sheets at your command line. Pretty neat utility.8 -
Just thought I'd share my current project: Taking an old ISA sound card I got off eBay and wiring it up to an Arduino to control its OPL3 synth from a MIDI keyboard. I have it mostly working now.
No intention to play audio samples, so I've not bothered with any of the DMA stuff - just MIDI (MPU-401 UART) and OPL3.
It has involved learning the pinout of the ISA bus connectors, figuring out which ones are actually used for this card, ignoring the standards a little (hello, amplifier chip that is wired up to the +12V line but which still happily works at +5V...)
Most of the wires going to it are for each bit of the 16-bit address and 8-bit data. Using a couple of shift registers for the address, and a universal shift register for the data. Wrote some fairly primitive ISA bus read/write code, but it was really slow. Eventually found out about SPI and re-wrote the code to use that and it became very fast. Had trouble with some timings, fixed those.
The card is an ISA Plug and Play card, meaning before I could use it I had to tell it what resources to use. Linux driver code and some reverse-engineering of the official Windows/DOS drivers got me past this stage.
Wired up IRQ 5 to an Arduino interrupt to deal with incoming MIDI data, with a routine that buffers it. Ran into trouble with the interrupt happening during I/O and needing to do some I/O inside the handler and had to set a flag to decide whether to disable/re-enable interrupts during I/O.
It looks like total chaos, but the various wires going across the breadboard are mainly to make it easier to deal with the 16-bit address and 8-bit data lines. The LEDs were initially used to check what addresses/data were being sent, but now only one of them is connected and indicates when the interrupt handler is executing.
There's still a lot to do after that though - MIDI and OPL3 are two completely different things so I had to write some code to manage the different "channels" of the OPL3 chip. I have it playing multiple notes at the same time but need to make it able to control the various settings over MIDI. Eventually I might add some physical controls to it and get a PCB made.
The fun part is, I only vaguely know what I'm doing with the electronics side of this. I didn't know what a "shift register" was before this project, nor anything about the workings of the ISA bus. I knew a bit about MIDI (both the protocol and generally how the MPU-401 UART works) along with the operation of a sound card from a driver/software perspective, but everything else is pretty new to me.
As a useful little extra, I made some "fake" components that I can build the software against on a PC, to run some tests before uploading it to the Arduino (mostly just prints out the addresses it is going to try and write to).46 -
When you a Visual learner
Learning Beziér Curve📈📉. I like learning thing visually, it helps me figure something out easily.
Do you too?9 -
!rant
Four hours of work.
You think you write spaghetti code? I write spaghetti wires.
H-Bridge dual motor tester for stepper motors.
Speed is controled by pot.
H-bride are L293D.
My third board, and the first that won't go to the trash.
Question. With the baterry off the motor continues spinning with the 5v from arduino.
My question is, is the L293D suposed to do that? Or do I have a short circuit somewhere that is giving power to the motor? Meaning it can burn the arduino.
Runs a 12v stepper from a CD-Rom driver perfectly at 5v from the arduino and actually starts to act strange when I turn the 12v on. (maby the circuit it's adding 12v + 5v?)24 -
Dear Chrome/firefox developers,
If someone presses the back button after they click on a link it means don't load that page and not go back to previous page.4 -
Finally, the jeezless present is done.. fuck this shit, where's my booze and my bed?! 😒
Anyway, it's essentially a power bank with LED's attached to it. The LED matrix is at the back side and looks reasonably decent (but I don't wanna disclose the age it's displaying). It's powered through a 47ohm resistor and is directly attached to the 5V lines. Yellow LED's with 2V voltage drop that have each number completely parallelized, and then those numbers are put in series to increase the combined forward voltage of the LED's to 4V. That way the circuit is around 80% efficient (resistor drops 1V, LED's drop the remaining 4V). Other than that, nothing too special. It did take 2 nights to build though.. way too much for a mere formality 😑13 -
I love this database primarily because it is cross platform and can be easily understood by anyone unlike SQL database files.5
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If we are living in a simulation then I am pretty sure that the quantum mechanics part was written in javascript.3
-
iPhones are ridiculously picky when it comes to finding a mate- um charger. And knowing why doesn't really make it any easier to understand why. If anything it baffles me more.
So, let's start with appliances that are not phones. Think Bluetooth headsets, keyboards, earbuds, whatever. Those are simple devices. They see 5V on the VCC line and 0V on ground, and they will charge at whatever current they are meant to. Usually it will not exceed 200mA, and the USB 2.0 spec allows for up to 500mA from any USB outlet. So that's perfectly reasonable to be done without any fuss whatsoever.
Phones on the other hand are smarter.. some might say too smart for their own good. In this case I will only cover Android phones, because while they are smarter than they perhaps should be, they are still reasonable.
So if you connect an Android phone to the same 5V VCC and 0V ground, while leaving the data lines floating, the phone will charge at 500mA. This is exactly to be within USB 2.0 spec, as mentioned earlier. Without the data lines, the phone has no way to tell whether it *can* pull more, without *actually* trying to pull more (potentially frying a charger that's not rated for it). Now in an Android phone you can tell it to pull more, in a fairly straightforward way. You just short the data lines together, and the phone will recognize this as a simple charger that it can pull 1A from. Note that shorting data lines is not a bad thing, we do it all the time. It is just another term for making a connection between 2 points. Android does this right. Also note that shorted data lines cannot be used to send data. They are inherently pulled to the same voltage level, probably 0V but not sure.
And then the iPhones come in, Thinking Different. The iPhones require you to pull the data lines to some very specific voltage levels. And of course it's terribly documented because iSheep just trying to use their Apple original white nugget charger overseas and shit like that. I do not know which voltage levels they are (please let me know!), but it is certainly not a regular short. Now you connect the iPhone to, say, a laptop or something to charge. An Android phone would just charge while keeping data transmission disabled (because they can be left floating or shorted). This is for security reasons mostly, preventing e.g. a malicious computer from messing with it. An iPhone needs to be unlocked to just charge the damn thing. I'm fairly sure that that's because the data lines need to be pulled up, which could in theory enable a malicious computer to still get some information in or out of it. USB data transmission works at at least 200mV difference between the data lines. It could be more than that. So you need to unlock it.
Apple, how about you just short your goddamn data lines too like everyone else? And while you're at it, get rid of this Lightning connector. I get it, micro USB was too hard for your users. I guess they are blind pigs after all. But USB-C solved all of that and more. The only difference I can think of is that the Lightning connector can be a single board with pads on either side on the connector, while in USB-C that could be at the socket end (socket being less common to be replaced). And at the end of the day, that really doesn't matter with all the other things that will break first.
Think Different. Think Retarded. Such tiny batteries and you can't even fucking charge them properly.6 -
FFUUUuucccckkk me sideways. So I decided to look into USB type-c's power delivery and alt modes. Cause I kinda want to make an adapter card to run my displays over a single cable. TLDR of the rest: USB-C has some huge capabilities which noone is interested in using since its way to complex to handle for what its worth in the end.
Now PD alone is kinda ok to deal with since a lot of powerbanks use it and some hobby guys documented how to work with it. I find it really odd thou that you NEED to use a dedicated IC for using the configuration chanel to negotiate how much power you can draw. Why the USB standard didnt use some simple 5V low speed signalling? Also the standard says that you only have to implement 5v 0.6A with every other power level being optional. (This is also true for cables. Most manufacturers use only the USB 2.0 standard for them and brag about how fast type-C is. ლ(ಠ益ಠლ) )
Now to the alt modes. These motherfuckers are a real shitshow to deal with. First you need a Mux to deal with USB-C's two way insertion, so your signals wont get flipped. Next thing is that you have four lanes at your disposal in alt mode. Which you can either use for four Display Port Lanes or two DP lanes and two USB 3.0 lanes. (You always get USB 2.0) Now you may think that there would be one simple chip to do it all? Nope you need atleast two at the price of 6$ each. One for PD and one for Alt modes. Both are very hard to solder (QFN, 0.5 mm pitch 40+ pins) TI ended up being the only one with a decent offering of IC's that do what I need. As for working with them, you would think that you just slap a simple MCU on there that communicates over I2C or SPI to configure the chips? Nope! You program the chips memory from which it configures itsself. And the programming is done with some TI tool which gives me no idea as to how you can handle everything whith no control logic behind it.
Looking into alternative IC's leaves me with cypress semi. And their documentation is basically a total mess. I wanna know what that chip is good for and what I need to do to make it work. I dont care about technical details mixed with marketing jargon nobody understands. And I really despise that I have to register just to download a datasheet. Especially since there is no info about it on the main page.
And this whole rant hasnt even touched the topic that USB-C only uses DP and nothing else. So you better hope that you have DP++ so you can use a passive conversion.
This was my Ted Talk about USB-C. Some info in it may be subject to my stupidity and errors as it currently is 02:15 in the morning and I need some sleep.14 -
"Intense coding. A day passes. Wait, how the fuck did my code work? It doesn't make any sense!"
It happens so, so often, God why 😐1 -
Any idea how to make a fan in an HP laptop spin at lower temperatures? The fan in my Pavilion dm-1 only starts spinning when CPU reaches 75°C and enters full speed when the GPU also becomes 75°C. Which is strange because this CPU and GPU are one and the same thing.. an APU. And overheating freezes often happen at around 75-80°C.. which isn't too much of a headroom really. I'd rather have it kick in at 50-60°C already, but would like to avoid using the power of the soldering iron for it.. I've already lost a fan to that previously (current one is a spare part from AliExpress). Granted, my soldering experience was much less back then.. nowadays I can probably even solder 1206 SMD packages comfortably. But I don't want to risk it, and I've got experience with custom kernels anyway.. are there any fan speed governors in the kernel that you know of?
FWIW, fancontrol doesn't seem to be supported on this laptop, and neither is pwmconfig. Perhaps I'll have to stick to the electronics method after all? Given that it's just a 5V fan, I guess that I could feed it power by tapping some power from a USB rail and controlling its speed from an ATtiny85.. but inside the laptop there isn't enough space for that and I don't feel like freeing this hardware out of its laptop chassis yet (though that is on the list). Either way running at 60°C under no load is terrible.. some HP certified enganeering "feature" I guess...4 -
What if - when you want to switch off the light or anything, you are supposed to get electrocuted and die.
But instead, your consciousness switched to an alternate reality and live, and you wouldn't notice.
Jeez..I need to stop watching scifi. I wont look at switched the same again.2 -
Dev.to app asks me to type in my github username and password into the github login page opened in their app. Is there no better way to do OAuth on Android apps?8
-
Went to an interview.
Interviewer said "X language is easy compare to our stack".
The next month, I saw on a job post that they're looking for that X role.
I should buy some sandwich2 -
Buys a product on amazon.
"Intelligent" ML based Amazon backend services: This guy just ordered a product. He might not want to see any ads showing him the exact same product because he already bought it and will not want to buy another until he loses the first one which might take a while.
Result:
User.showAdsRelatedTo(productName)
Meshine learning ¯\_(ツ)_/¯7 -
Flex + CSS grids is awesome. I know I am late. I regret not realizing this earlier. Way earlier.
Someone who does not agree with me please read this: https://css-tricks.com/snippets/...4 -
The Turbografx 16 (or Turbografx PC-Engine in Japan) has the most amazing fucking expansion port I've ever seen. Every bus is exposed, plus sound out and IN (unused by anything ever made for the thing), composite out (not included on the console itself, but 3rd-party addons allowed it), VGA out (!!!) and CPU HALTING/CLOCK CONTROL were included over this fucking thing.
You can even power the system with 5v in through the expansion port and bypass the power switch with it.
Info and diagram:
https://gamesx.com/misctech/...
Example:
To get composite out, send pin A22 out and ground the ground wire of the composite to any ground.
For VGA, it's a little more complex:
VGA1 to TG-A23, VGA2 to TG-B23, VGA3 to TG-C23, VGA9 to TG-A2, VGA13 (and VGA10 if you want compatibility with older displays) to TG-B11, VGA14 to TG-A10, VGA5-8 (and 10 if not hooked to TG-B11) to TG-C2
(VGA numbering from Wikipedia diagram)
this thing's fucking coolrant holy fuck this is cool turbografx 16 expansion port heaven expansion port console mod turbografx pc-engine1 -
First day of holiday - manager messages that about small issues, ignored that.
Second day of holiday - received a message that everything is going wrong. Apparently I can't take any holidays as the world will burn in the meantime...3 -
I think I can learn English here.
HAHAHA
I can also learn professional knowledge.
**I am a Korean.**
And...
Succeed!
Android studio AVD powered pictures4 -
My Unix class
👨💻using nice looking theme for vs code to edit my bash script
Prof: That's a nice looking theme( he thought it was vim theme)
Me: um.. um.. It's vs code, new guy in a town
Prof: uh! 🤔
Me: ( 5 sec silence) um, It's from Microsoft
Prof: GET OUT!3 -
Can someone explain the node_modules joke to me please? I've seen it quite a bit now, but I still don't get it. (Attached an example from https://devrant.com/rants/760537/...). Thanks in advance.5
-
Didn't even ask for 2 sets, the devRant team is just awesome! Thanks!
On and @localhost, it seems like people are sending their setup, so here's my student one :)1 -
How to spend more time writing docs then code?
15m = doc
1m = code
<code>
/* Motor DC + Mosfet IRF520 + Servo
Materials:
IRF520 (Mosfet) + Dc motor + Batery (3V min)
diode (1N4007?)
Changed Tip122 for IRF520: Tip122 has less resistance and produces more heat
Hardware:
ARDUINO = A(port , 5V , GND)
MOSFET = M(A[port] , + , GND)
MOTOR = MOTOR(+ , -)
BATERIA = BAT(+ , -)
DIODO = D(sinal_1 , sinal_2)
MOSFET
M(port) = A(port)
M(+) = D(sinal_1) AND MOTOR(+)
M(GND) = A(GND)
D(sinal_2) = B(+) AND MOTOR(-)
ARDUINO
A(port) = M(port)
5V = null
A(GND) = M(GND) AND BAT(-)
*/
#define motorPIN 8 // A(port)
int loopy = 0; // Loop variable to limit de program
void setup()
{
// Initialize the motor pin as an output:
pinMode(motorPIN, OUTPUT);
}
void loop() // 1 loop == 100ms
{
if (loopy < 10) // Turns motor ON for 1 second
{
digitalWrite(motorPIN, HIGH);
}
else // Turns motor OFF
{
digitalWrite(motorPIN, LOW);
}
}
</code>22 -
Hey guys.
This was my project for today.
Power supply, 5v USB 25A x2; 12V 10A x2; extra power standard cables to power HDDs and such.
Plus a sand paper whatever it's called :p
Ps: Need to know how to power it without the standart power supply, with cables direct to the brush motor pins. Anyone knows? Have arduinos, l293, easy shields, uln2003a... Would one of this work?
Hope you guys like my 🤪 ideas5 -
I actually found a real website using a Spinner UI element for inputting phone numbers!
It accepts typing the number too, though. So not completely bad. Also it only appears in the desktop version.
I guess this was just some short cut to force numerical input. Still was pretty shocked. I've only seen them in jokes/memes.
site: http://www.sparrowinn.in/1 -
Hey Guys
Safety Question.
If I charge a 220v capacitor with 5v... Does it accumulate up to 220v or just the voltage I give it? Thanks14 -
Fuck you stackoverflow. You should have told me this before I changed my username. Did you expect me to know this somehow???9
-
I finally found something to rant about! So what happened is that I am participating in the Digital Ocean competition (I need to do 5PR's). So I find a report with a lot of scripts. I decide to contribute and write a discord webhook API (send messages through a webhook). The next day, the guy goes "No thanks :)" and closes the PR. Words cannot express how triggered I am. I ask him if I can make anything else out of exasperation (I did not intend to do anything for him anymore, I can't explain why I did that), he tells me no...
;(3 -
What's the most efficient motor driver for a small DC motor that I want to run off a 5V source for aurdino?
I previously had a L293D and it was inefficient as fuck, it got so hot that almost burnt my finger, (ran it from a 12V supply) and it dropped a good 2 volts from power supply to motor.
Is there a good enough off the shelf driver or do I have to make a H-bridge myself using MOFSETs?6 -
I just wanted to develop a cool webapp-controlled lighting for my bar.
Next things I know, there is electronics scattered everywhere, 2 multimeters to find what the fck is wrong with a PSU not outputting 1/100 of the current it's supposed to, said PSU opened on my desk, and I'm trying to find a capacitor online because there isn't any fcking electronics store selling spare parts anymore in my city.
Context:
- PSU means Power Supply Unit, in this case a computer one.
- PSU was given by a friend and is out of warranty
- the total consumption for all LEDs is 24A @ 5V consumption. A refurbished PSU is ideal for that
- that PSU is rated 2A @ 5V on the stand-by, which is perfect to power a Raspberry Pi. The issue is that there is a sharp voltage drop as soon as you try to use more than 20mA.9 -
Does anyone else get triggered when you use the python socket .recv() and the server does not return anything so the program just stays there indefinitely? For me, I can't even Ctrl+C it so I have to close the entire window. It's especially annoying when I start a server in the interpreter (quite a bit of lines) and I have to rewrite it afterwards.7
-
Now... I understand 2FA is to make things more secure, and I do appreciate it. BUT can we please work out a damn solution for people who work in an agency for other corporates which only have one shared account across the agency that bundles one phone number or mobile app.
What if people are on leave or sick? I need stupid 2FA to be able to login/work. uhhhhhhh.....9 -
Anyone else think it would be easier if the ++ was on the right. Makes me think there should be a left and right handed option for apps.10
-
All code and no tests makes a software buggy, hard to maintain and a pain in the ass to work with.3
-
Just noticed github shows Infinite contributors for chromium repository. (https://github.com/chromium/...).
Also, I clicked on the contributors tab and the page is still loading. Guess it will take infinite amount of time to finish loading :?3 -
So, I've been trying to learn assembly. However, I can't find any assembly docs online, so I can't really do anything. I tried NASM and FASM but I just can't understand assembly. Do y'all know any decent way to learn assembly? (My dad said it's better to do it on my pi or should I do it on my desktop?)8
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My Data Communication & Computer Networks (DCCN) teacher was the best teacher I've seen.
Teaching can be super hard. You're one against like sixty others who aren't interested in being there. To make that good learning environment, making the subject interesting etc, it not easy. Some justify that, "I can only bring the horse to the water" & proceed to just regurgitate whatever is on the book. Others cross question you & impose punishments - try to make you learn by fear.
But my DCCN teacher - she had the right balance between strictness & humour. So kids took her seriously (did homework, weren't late), yet never feared her - we felt comfortable asking doubts/questions.
She had some good tactics, like asking us to teach certian chapters - that made us learn better. She would revise them in the end also, incase we missed anything.
My best moment with her was when I scored the highest in my internals. She picked up my paper & showed the class - "see? Just two pages & he scored so much". There's was always those students who pump out a lot of stories/essays or whatever that comes to their mind about the topic in question. Lots of teachers just blindly give marks - "oh, s/he wrote this much, so it must be right".
But my DCCN teacher had zero tolerance for garbage. If you're wrong, you're wrong. Some even believe that the number of marks = number of lines you have to write!! Doesn't matter what you write. So, I was super glad when this teacher upped the standards. -
I just finished my second semester of computer programming. I then say to myself : "Let's use my new knowledge to make the program I worked on for fun two years ago better and more efficient!".
It was a bad idea. -
Me: What's this new icon in the app?
* Long press on the icon *
Nothing
Me: Huh. Ok. I will press it and see what it does.
* Presses it *
You have successfully done what you did not want to do. Congratulations!
WTF! Just tell me what it does when I long press it.1 -
Why the fuck does a freaking SD card reader for arduino needs a 3v and a 5v pin...... I have no space in my project and no experience at all to handle this.... and no fucking place for batteries....
Why is every of my project like this ..... cry12 -
This extension is awesome. You can have dark theme on every website. Although sometimes it fucks up the website layout a bit.
https://addons.mozilla.org/en-US/...3 -
We're finishing some projects for uni. I've done mine, and am just helping out with others.
There was a friend who is doing her write-up. My other buddy was just just troubling her for fun. He threatened to press the power button on the laptop, thus sending it to hibernate. Minor nuisance; she just need to turn it back on after all.
She pleaded to leave her & let her complete the write-up. So I asked her if I could quickly re-configure the power button. You know, go to the windows power settings, and tell it to do nothing upon pressing the button.
She said no. But the way she said it struck me odd. As in "No, why would anyone do that!?". Debatable. Just to make sure, I asked whether she understood what I requested. She made a quick hand gesture of plucking the power button off!! 😐
Me & my buddy just stare at each other. "Yeah you're right, you're right, what a stupid idea...". We just slowly scoot from there. 🏃
No idea how she reached this far...1 -
Any recommendations for introductory books on electrical engineering? I'm looking for something that goes into detail on the basics: tension, current, resistance, inductance, capacitance, etc. I have very little knowledge on the subject (I know what the basic components do and that's it) and I found myself struggling a bit with the most basic concept: voltage.
I grabbed my multimeter, a few resistors and a battery and played around a bit. For some reason it doesn't really "click" why on a 5v circuit with 3 2.2k ohm resistors (I think) the voltage around each resistor was like ~1.3 volts or something, while on a circuit with 2 resistors the voltage accross each one was ~2.3 something volts (I don't remember exact values). Like, I know that voltage is a difference in potential, but I still don't get it and idk what I'm missing. Why is the difference in potential accross a resistor different if the circuit has 2 resistors in series instead of 3. It kinda makes sense in my head but at the same time it doesn't.
In short, I want to know the "why" stuff works the way it does, not just the "how".
Also, if the book covers common practices, components, and circuits that'd be very helpful. I want to learn how to build well-designed, reliable and safe circuits.11 -
Lets reinstall my Linux. Step 1 reformat from Windows 10 in your dule boot system and delete Linux partion. Step 2 boot up in bios.... The first time you do this, is the last time you do this.... I hate grub rescue.1
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Nothing beats when you move into a new team and your old team message you all the time for those little things they could Google... Did people really think I was that smart??? Maybe some people are better at googling than others...
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Fuck this shit. Any socket connection on JIO's fucking network gets dropped after 5 seconds if no data is sent. It's working on any other network. Wtf is going on???
Does anyone have any idea on this?
If someone has jio network please go to https://www.websocket.org/echo.html
And connect and check how long until it gets disconnected. Would be greatful if someone can validate this.
The project I am working on uses websockets extensively and this thing is screwing it up. I have temporarily set websocket ping interval to 3 seconds but what if the f**ckers over at JIO decide to start dropping connections every 1 second?7 -
Definitely Android 8.0 is neat.
And it's faster.
I think Android has developed a lot.
Isn't that right? -
Just ordered myself a raspberry pi 3 B+ and i was wondering if any one you have this already .. and if it works with a samsung charger 2A at 5V ?5
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Question for the electrically minded.
I have a laptop with a 19v input.
I have a portable UPC with 2 voltage options in the range of this, I can undervolt at 16v (the laptop battery voltage) which works with a small firmware correction to ignore a board sensor, the other option is to slightly overvolt to 19.5v which I assume the laptop could handle through its input regulation.
Can anyone confirm if a .5v variance at charger is within tolerance? It would be an overvolt of 2.5%5 -
Started my very first (summer) job as an IT agent in customer service for my city less than two weeks ago and finally moving out from the formations to answer the phone alone.
I must've listened to around 30 calls and already there's stories I could make tales of.
I now understand the job of customer service. -
Arduino + breadboard power supply MB102.
Noob question I know, but how do I connect the power supply to the arduino? 5v to 5v and GND to GND? Or vin? Or the other first pin above res?
Help?
@Condor50 -
Hey Postman,
Please fucking stop downloading minor updates and bug fixes automatically. Even if you do it, give the users an option to cancel the fucking download so that they can, you know, peacefully use the app for what it was built for.7 -
Electronics question:
Potentiometers
Hey guys. I'm searching for potentiometer calculators but I have a problem...
Where do I get the R1 and R2 for a given pot?
I wanted to know what pot should I use to regulate 0-12V and 0-5V.
Also, can this potentiometer handle a 400w power supply current?:
https://build-electronic-circuits.com/...
I'm designing the box for my power supply and I want to regulate the voltage on one of the exits.9 -
My unidirectional type-c cable. Essentially is a Type C to Type A-female adapter with a Type A to Type C cable plugged in, but with the plugs bypassed with a soldered joint.
Useful for devices that have Type C but refuse to implement protocols, just using 5v bus. They only work with Type A to Type C cables. Usually, they’re vapes and other low-cost devices.
I made this cable to charge my heated tobacco device. Now, since I quit smoking, I don’t need it anymore, but I’ll keep it nonetheless because it’s kinda neat.1 -
Just typed this into the Python interpreter and my whole system just froze. Guess I have to do a force shutdown.
x = list(range(1, 999999999))
So is there a way you can somehow configure your linux system such that the window manager/system is never out of memory or processor time? So that atleast I get can atleast kill the process which is freezing the system.3 -
Tried to install MS-DOS 6.22. Was not fun at all. Tried 3 iso flashers in total. The closest that happened to DOS was unetbootin getting bootlooped on the 10 second countdown to automatic system start. I gave up on it eventually.
:\7 -
Those of you who wants the bleeding edge of technology, here's the one for YouTube:
https://youtu.be/addme/...
This unlocks the sharing tab on YouTube's mobile app, like in the screenshot below. Make sure you are on your mobile device.
Enjoy sharing! :D
//Oh right, it's supposed to be a rant -
Gosh I hate when I ain't in the new technologic stuff already 'ghah 😡 😋1 -
I keep getting emails from people I don't know that are like conversations, leading me to believe they aren't sent to the rightful owner. Most of the time, I see the email has uppercase at some places (when mine doesn't).
I just wish the companies could put a mark somewhere in their page when entering an uppercase email that mentions the fact that it doesn't change shit, getting really annoyed from receiving these mails not directed to me 😒 -
Unlocking your potential takes time.
Throwing away time is so easy to do and we are all guilty of it. How much of your time have you wasted not living up to your potential? The answer is brutal and may overwhelm you.
You have probably wasted some of your time but at least you haven’t wasted your whole life, yet.
You still have time and that’s the best reason to stop wasting it and unlock more of your potential. It hurts to know you have been lazy or procrastinated, but it hurts even more to ignore that fact and pretend everything is great.
source: https://psiloveyou.xyz/overwhelming... -
💡 Have an idea to develop a system
*browse what language to use
*browse what template to use
*meh, I should write my own template cause I'm too smart
*F it, I realized im dumb, back to browse template
*browse why x better than y
*browse which company use x
*browse which hosting to use
*find admin template
*browse cat fighting with subtitle
This rabbit hole. And the project hasn't started yet for weeks and months. -
Has anyone developed websocket server in Nodejs?
I am planning to use socketcluster. Has anyone had experience using it? Is it good or should I go for something else?11 -
How do you tell someone their code sucks?? Like why dont you indent?? What's wrong with using useful class names? At least chuck a comment in there...
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2 weeks of grub rescue, windows 10, Windows xp, Linux mint cinnamon, Linux mint MATE, bios, cmos, squashfs error, debian and unetbootin.... Thanks to rufus and Ubuntu we're now back on track. I've just gone from computer tinker to computer badass B-)