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 Discussion on question by Juan Jimene…

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StarCat
Oct 28, 2023 00:14
2 V AGM cells exist. You could at least approximate 9.6 V with 4 or 5 of them in series.
 

 Discussion on question by LearningBas…

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StarCat
Sep 15, 2021 16:35
Like I said, what you ask is not very clear to me. You seem to define "pull-up" differently to how it is normally used.
StarCat
Sep 15, 2021 16:35
@LearningBasicComputerScience the "path of least resistance" refers to when the button is pushed. The path to ground through the closed button will be much lower resistance (essentially zero). But I think this does not answer your question (which is not very clear to me at the moment). It's all basic electronics however.
StarCat
Sep 15, 2021 16:35
A pull-up is usually used when a (digital) input needs a defined value when it’s not driven by any other signals. For example when a button is connected to “ground” on one side but it’s not pushed, its output just floats, but a pull-up on the output of the button will give it a defined “high” value so the input it’s connected to will read “high” and not pick up noise. When the button is pressed it becomes connected to a “low” voltage via a low-resistance path which will “win” (because its resistance to ground is lower than the pull-up resistance) and “pull” the output of the button low.
 

 Discussion on question by Bukaida: Ca…

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StarCat
Sep 13, 2021 10:43
You could take all the "noTone()" (or equivalent digitalWrite()) commands out of the "if () { ... } " blocks as all of them turn off the buzzer. At least you now know that the buzzer is turned off every loop(). It looks like you are turning the buzzer on for a very short time (20ms which is 1/50 of a second). Is that what you want? It would also help if you properly indented the code to make your decision structure clearer. You are familiar with Python so that should be second nature to you ;-)
 

 Discussion on question by Someone_who…

Imported from a comment discussion on retrocomputing.stackexch...
StarCat
Jun 10, 2021 07:18
@ReversedEngineer But, but, but... we also have Internet Protocol, Intellectual Property and possbly even more IPs so CPU manufacturers have to look for something else again :-( There are just not enough TLAs (Two Letter Acrynoms, or is it Three Letter Acronyms? Oh well...).
 

 Discussion on question by Joey: How t…

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StarCat
Mar 7, 2021 01:33
1mm2 of copper wire is about 17-18 ohms per kilometer. The rest follows from that. I work a lot with 12V systems on my boat so I know how important wire cross-section is with low voltages and high currents and how to calculate cable losses.
StarCat
Mar 7, 2021 01:33
I see I’ve made an error and did not account for the round trip. Still, 1.5mm2 is about right for your situation (1.2 A).
StarCat
Mar 7, 2021 01:33
@Joey, I see. For a 3.2A load, 8m of cable and a loss of less than 2% (0.24V) you’d need 2mm2 or thicker wire. For 1.2A you would need about 1mm2 at a minimum, but I would use at least 1.5mm2.
StarCat
Mar 7, 2021 01:33
@Joey, ” I see even with a 1.2A LED strip the maximum resistance is 0.2 ohms” how so?
StarCat
Mar 7, 2021 01:33
39 Ohms per kilometer is about 0.5mm2 if the material used is copper. This is very thin.
 

 Discussion on question by Scientific …

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StarCat
Dec 20, 2020 05:04
I think Arduino (the 8-bit AVR variety) might not be the right platform for that. Look into setting up a distributed network of (cheap) ESP8266/NodeMCUs, the Tasmota platform (for example) and setting up an MQTT broker on the Raspberry Pi. Your problem has already been solved. You're free to develop your own platform however.
 

 Discussion on question by Carl Levass…

Imported from a comment discussion on arduino.stackexchange.co...
StarCat
Dec 8, 2020 21:32
I don'tknow exactly what JST you're refering to, but it should include ground. It was just that your schematic did not show connected grounds. If they really were not connected, that could be a source of trouble.
StarCat
Dec 8, 2020 21:32
Where are all the grounds connected to? From your schematic it's not clear if they're all connected (which they should be).
 

 Discussion on question by azad.parind…

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StarCat
Nov 23, 2020 18:13
Your schematic makes little sense. What is the function of the relay? Is the relay coil really connected to +12V through a 10K resistor? Are the grounds of the motor and the relay/12V supply connected? Also, the MOSFET is rated for 60V which is perilously close (too close) to the 54.6V that the motor is supplied with.
 

 Discussion on question by yeganehhp: …

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StarCat
Nov 14, 2020 23:47
Whatever multi-threading is, it isn't really relevant to this question. The article that @yeganehhp refers to in their question is not about multithreading but about creating non-blocking code. Now if they would clarify and add some relevant background to the question we might actually be able to answer it. I still think this belongs in Arduino Stack Exchange where this kind of question comes up often, like in this question.
StarCat
Nov 14, 2020 23:47
Please consider moving this to the Arduino Stack Exchange. BTW your question lacks any detail about what you are trying to achieve (communicate at the same time is not really a description). I'm almost sure you don't really want to "multi thread" on an Arduino but just want to avoid "blocking" code. Outline what you want your code to do, or show code you already have that you're having problems with.
 

 Discussion on question by Tiago Kotry…

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StarCat
Sep 14, 2020 08:40
Have you ever set the clock on the DS1302, like the commented-out section after Serial.begin(9600); shows you?
 

 Discussion on question by DEEPPRAKASH…

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StarCat
Sep 10, 2020 16:53
"Could it be a faulty batch of 7805 ICs, or is there something wrong with my meter?" with the information you've given, it's impossible to tell. Have you tried with a different meter? With a known good +5V source?
 

 Discussion on answer by Codebreaker00…

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StarCat
Apr 14, 2020 17:25
Why don't you answer Codebreaker007's questions first? And please read the compiler error messages. They can be really helpful.
 

 Discussion on question by AndreiMusat…

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StarCat
Mar 3, 2020 14:56
@AndreiMusat, I agree with Gerben that it's probably a good idea to put a 100nF bypass capacitor between pins 7 and 8 of the ATMega328. The current Reset circuit should work fine without external "help". It's possible that your fuses were programmed incorrectly but that should not have happened (and still does not explain why your ATMega only resets when connected to the Arduino Uno board).
StarCat
Mar 3, 2020 14:56
The simple circuit (with pull-up resistor and a button for pulling Reset low), like in your topmost breadboard, should just work. Make sure you have not rotated the button by 90 degrees (permanently connecting Reset to ground).
 

 Discussion on question by ShoutOutAnd…

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StarCat
Feb 22, 2020 21:40
@ShoutOutAndCalculate, The NodeMCU (v3) I have been testing with has the CH340 (no problems with instability). But I can't think of any reason why this would make my MPU6050 work and yours not.
StarCat
Feb 22, 2020 21:40
@ShoutOutAndCalculate, No, V3 is not official and there is no technical difference between a V2 and a V3 except for some unimportant differences in pinout. It's mostly just marketing.
StarCat
Feb 22, 2020 21:40
One more question: Do you run your ESP8266 at 80 or 160Mhz? Mine run at 80 by default but I've not yet come across a situation in which I need the extra speed. Edit: At 160Mhz the sketch from case 6 still worked well.
StarCat
Feb 22, 2020 21:40
@ShoutOutAndCalculate, My NodeMCU is a brandless "NodeMCU v3" (the wide breadboard-unfriendly version). The script from case 6 worked (I did change the SCL and SDA pin numbers and the serial speed to 115200). The Gyro and Acceleration values looked correct to me (i.e. rotating along different axes produced consistent results). BTW, what results do you get? What happens exactly?
StarCat
Feb 22, 2020 21:40
@Juraj, I see what you mean. I assumed the yellow tape was put there by the factory, but it does look suspicious.
StarCat
Feb 22, 2020 21:40
@Juraj, Good point as they are often delivered without a pin header attached. ShoutOutAndCalculate tested multiple working MPU6050s.
StarCat
Feb 22, 2020 21:40
I've actually built the same setup here (Generic ESP8266-12E "NodeMCU", generic MPU6050 board). I'm using the Adafruit MPU6050 library and it worked out of the box with the supplied library examples. My MPU 6050 is supplied from +5V, no pull ups on the I2C pins, no twisted cables.
StarCat
Feb 22, 2020 21:40
The MPU6050 boards I found need a +5V supply voltage as they have an internal 5V->3.3V voltage regulator. I would try to connect the yellow wire to your MPU6050 to +5V instead of 3.3V. It also looks like pull up resistors are already on the board so I would leave them out (if you have the same board), See this schematic