New answers tagged

0

Yes you can - but you will invariably need some sort of control interface. You need to say whether you want just on/off control, or variable speed, and/or variable direction - and what degree of speed control accuracy you want. Also rate of change of speed, accuracy/resolution, braking control aspects etc. And are they brush type motors or "brushless"....


0

No, With motors it's not just voltage its also current. V*I=P so its the combined power output of an ardunio uno vs the power required to drive the motors. You'll need a separate power system or driver to be able to drive 10 motors. Of course that depends on your motors I'm assuming no as you didnt spec your motors. But as an example lets say you have a ...


1

DS3231 has two registers that take care of alarms control and status, and also of oscillator. After the alarm is triggered, you need to clear appropriate registers in order to set new alarm. There is also a problem with oscillator not working when DS3231 is operating only on VBAT. There are also few bits in Status and Control registers that set behaviour of ...


0

When I remove the ground port near the Diodes, the value read by Arduino become absurd, is there any way to measure the load current without grounding the diodes by using the similar configuration? No, not using anything similar. Think about what voltages are produced on the output of the three phase rectifier. The cathode's of D1, D2 and D3 will ...


0

You need to have a reference potential somewhere, anyway. If the source is grounded, than you already have it. If it's floating, then you may attach a ground like you did. In case a source already has a connection to ground, then you have to pay attention on max. common mode voltage of difference amlpifier. The schematisc is not very clear, a clearer view ...


2

Your circuit's incorrect, try this. simulate this circuit – Schematic created using CircuitLab For BT136 to switch on you must make a voltage difference (positive or negative) between the gate and A1 which happens, with this circuit, after mains zero crossing. The triac triggers in quadrants I and III thereby avoiding quadrant IV triggering. RG is ...


0

The default reference should be 5V, fed from Vcc to Aref by way of an internal reference select multiplexer. If might be less than 5V if the board is powered from USB. Measure your 5V source - is that varying as well?


1

I cannot exclude that the circuit can principally work (as per PCB layout; your schematic is currently wrong, at the time of this writing). The IRF740 should have plenty enough heat dissipation capability for 3W of continuous power (its abs max is given at 125W continuous), so I wouldn't be very concerned about RdsON, as long as the IRF740 FET is genuine (...


1

This answer is just to help you with your schematic. Figure 0. OP's schematic. It is badly laid out making it difficult to follow the schema of the circuit. There are numerous unnecessary kinks and cross-overs. BR1 is installed incorrectly. When V1 goes negative BR1 will short-circuit the mains supply and will be destroyed (as there is no fuse). Q1's ...


1

You need a transistor with much lower Ron. 1000W at 400V is 2.5A. Your transistor's Ron is .55 Ohm. That implies ~3W dissipated power, which is too much for a TO-220 package without a major heatsink. You should use a transistor with an Ron in the 10-20mOhm range.


0

Thanks all for your help. The following code now works without significant frequency measurement variation. The variations in my original code were caused by: 1) At prescaler = 1, any other interrupt that runs for more than 2*256*1/16mhz (32us) will delay the TIMER2_OVF ISR processing and result in an overflow interrupt being missed. For example, serial ...


-1

Conducted ground/supply noise and radiated EMI make your signals look noisy. Research on this site or web to consider how to shield, suppress, filters and isolate your offending motor noise cables away from the sensitive ones or any high impedance. Also avoid inductive loops, with low ESR supply caps then using MOSFET Half Bridge drivers instead. (BJT ...


1

thanks all for your answers. I managed to fix the problem just by grounding all unused inputs. I also re-soldered everything so maybe there was a faulty one and I also used only 1 ground pin of the ESP. If I have time I will try to do more tests in order to add more details to this answer.


0

The lock bits can be used to prevent reading the code memory with standard programming tools. It only works up to a certain point, as a determined hacker with right tools can still extract and clone the firmware. So you can use the lock bits but don't expect that it will be 100% effective.


0

Use hall effect sensors and magnets. Hall effect sensors are used for proximity sensing, positioning, speed detection, and current sensing applications.


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There are a few logic flaws in the elapsed time (period) measurement process. The system could instead be implemented as a state machine with (at least) these three states: ARMED, MEASURE, and DONE. FREQINT_STATE_ARMED. This is the starting state. The setup() function or the loop() function places the system into the ARMED state at time t=t0. Sometime later ...


1

Unless you actually measure the current out of the cell charger under load, don't count on the printed current rating. I have seen these types of chargers/ext power supplies go bad and unable to supply required load current but voltage readings are still good. Measure your load current draw when powered from your laptop. In the USB 1.0 and 2.0 specs, a ...


1

but i changed the source to a mobile charger Aha! Many mobile chargers (power banks) switch off when the load only draws a small current. This is likely the reason why the power is switched off. The Arduino + relay simply doesn't draw enough current to keep the power bank switched on. The power bank "thinks" there's nothing connected so it switches off. ...


2

You've clearly given this some thought, but some of the low-level details are tripping you up. I'm going to focus on one aspect of your problem, and maybe this will lead you into thinking in the right way to solve the rest of it. After doing a little research, I learned that Interrupts are not nested on the ATMEGA328 (at least, not by default) Timer 2 is ...


1

Also, I would like you to take a look at my unfinished code and ask if you could suggest anything. The not-equal comparison will not work well with a real analog signal because of noise gear10us = analogRead(A1); delayMicroseconds(10) if (gear10us != analogRead(A1)) { // ... } Suppose you stop your motor, and your sensor is staring at the same thing. ...


1

It has Cyclone10 FPGA from Intel. These FPGAs can be programmed with Quartus Software. Download it from Intel website. You can generate .bit files. I think, there are a lot of resource on the web. For example; https://github.com/vidor-libraries/VidorFPGA


2

The Schottky diodes are essential to protect the drivers from reverse voltage when power is abruptly disconnected with an inductive load. (Been There Done That with my OEM Buck driver on a few strings of LEDs THAT DID NOT SUCH PROTECTION and the drivers failed., so ordered a new one from Amazon and received in 2 days) I had an intermittent load connection ...


4

Somebody to know why ? Only the guy who drew the schematic. Most likely, they were just sloppy about what symbol they use for these things in their schematics. It's conceivable that they designed the thing years ago to use polarized capacitors, but changed to ceramics when 10 uF became affordable in an appropriate package. I guess the capacitor on ...


1

This is entirely a signal integrity issue using relatively high series impedance of the level shifter which is not good for driving inductive long cables with a Vol/Iol equivalent to about 800 Ohms max for port B. I would buffer them with HCT CMOS 5V logic that is closer to 50 ~75 Ohms and has a threshold of TTL = 1.4V or 74ACT series CMOS which is closer ...


1

A genuine TXS0108E has pull-ups on all pins (see Functional Diagram on page 18), so leaving data pins unconnected or touching unconnected pins should not have an impact. Considering the shop you got it from, it could be a counterfeit. Ask the seller to include a bunch of spare fingers with your purchase as the IC you got doesn't seem to work without them.


9

Why use 2 electrolytic capacitors instead of just one? That's often a choice, maybe 2 capacitors of 470 uF are cheaper / smaller / fit better than one 1000 uF capacitor. In high frequency switching power supplies a certain low value series resistance (ESR) is needed, that might be more easily achieved when using two capacitors Why no ceramic capacitors ...


0

If you're using the HAL you can use the HAL_UART_Receive() and HAL_UART_Transmit() functions to accomplish it. uint8_t data_byte; //try to read 1 byte from UART1 into data_byte; if(HAL_UART_Receive(&huart1, &data_byte, 1, 200) == HAL_OK) { //reading 1 byte successful, now transmit it on UART2 HAL_UART_Transmit(&huart2, &data_byte, 1,...


3

While this is an old post, I recently had this same problem when I was making an EEPROM burner for retrocomputing (where I needed to write some 27C512-style EEPROMs). The currently accepted answer has the correct idea (which I used), but it is missing the logic level (5V) control and protection, and pull-down on the output side. The following circuit adds ...


-1

Since you are speaking (in the comments) about accessing the ICSP connector, I assume you have direct access to the board. In this case, identifying the "arduino board" is pretty easy; almost all the boards have their name written in the overlay layer, so you just have to read it. Now, since this was pretty easy, I assume that your circuit is a custom ...


1

Although computer cooling fans draw low current, you can not feed them directly with Arduino. Typically, you need a buck or buck-boost converter that can be controlled by Arduino to change the input voltage of the cooling fans. But, you can simply use a ULN2803 L293, or L298 to control the fans by PWM. The speed of the fans is controlled by the duty cycle of ...


1

The Arduino in your photograph has a barrel jack on it for powering from a battery. A suitable battery pack is one like this. Battery Holder - 4x AA to barrel jack connector I teach Arduino robotics at the local university. As others have stated, use the computer and USB to actually program the Arduino, then remove it from the computer and simply run it ...


1

If your delay is related to data transfer speed(relatively if you transfer packages bigger than 200 kb), of course SIM7000E will be faster. As you can see below pictures, LTE has approximately 4 times faster than GPRS You can find more information to compare from these links : SIM800 SIM7000E


0

Yup. It is very easy. There are 2 ways: Provide 5-12 V on the Vin pin of arduino and connect (-) or ground to the ground on the arduino. You can also use an adapter whose output pin matches the black coloured jack on the arduino. Connect the programming cable to a mobile charger (USB port on the charger). For the 5-12 V source you can very easily use a ...


0

short answer: yes. The program is written on the controller and can run without computer. Powering an arduino via USB charger is done frequently and using a battery is well within the possiblities. I guess you will find quickly plenty of examples for that. If money and size is of essence and you are willing/abled to handle a "bare" µC outside the arduino eco ...


8

Flashing Once you upload your sketch to an Arduino, it does not need to be connected to a computer anymore; the Arduino IDE uploads the sketch into Flash of the Arduino, which will stay there until overwritten again, even when the Arduino is powered off and not connected to any power source. The uploading process is called Flashing (done by the Arduino IDE ...


1

Capacitance sensing may not be the easiest option. The measured capacitance may depend on things other then the distance to the hand. Ultrasonic sensors might be a better choice. That said, if you do want to go down the capacitance route, you probably want a Capacitance to digital converter. An example would be the Analog Devices AD7745 or AD7747. Both are ...


0

Try an Internet search using the keywords "Arduino bootloader". You'll easily find websites that discuss the inner workings of an Arduino board's bootloader. See also the data sheets on Microchip's website for their ATmega32u4 product. There you'll find a data sheet that describes the chip's "USB DFU bootloader." Also search for "USB CDC" or "USB ...


0

What I have suggested at arduino.cc is to use DPDT relays to connect each battery independently to an analog input and Gnd of Arduino that is powered indepently and Not grounded to the stack. Thus it would be like working a handheld multimeter across each battery. If you want to send data serially to something, optoisolated signals would be needed between ...


0

The batteries are all isolated? Or connected in series? Makes a big difference. If they are isolated, then you can also use 8-input ADC chips such as MCP3208 with SPI interface to quickly read them. You would connect SCK,MISO,MOSI to all of them, and then use a slave select to each one to access a channel at a time. 12 bit readings, and faster reads- about ...


0

You can use analog mux/demux iCs such as CD4051 (8 channels to 1). In fact, you can use 5 of them for the 36 batteries (you'd be left with 4 extra channels) and connect each to one analog input, and then connect all three control pins of each to the same three digital pins outputs in the Arduino. Then you'd be binary counting from 0 to 7 on those three pins ...


0

Have a look at I/O Expander. There you can control behaviour of individual pins or multiple pins in a batch. It is produced in different packaging for any application.


0

Forget about using a decoder at all. Simply drive the enables directly from pins on your MCU. Then you can select any combination, including more than two at a time if necessary. Note that to select an arbitrary combination of 0, 1 or 2 outputs, you need a total of 8 output pins from your MCU anyway (3 select bits and an enable bit for each of two decoders),...


0

Ideally, motor speed should be proportional to voltage, so it should remain constant regardless of torque. In reality however, increasing torque increases the current, which in turn results in more resistive losses in the motor. As a result, less voltage remains available to counter back-EMF, and the motor speed drops. Maintaining constant speed can be done ...


0

This is based on a few sources including the (poor) datasheet. My interpretation is that BIN should be connected to the previous LED's DIN. Then if the one LED fails, the next one will not receive any data on DIN, but it will receive data on BIN. It will switch to backup mode, where it uses the data from BIN, and ignores the data intended for the previous ...


1

The active buzzer, in my opinion, is worse. The active buzzer has a small sheet of metal inside. the metal vibrates when it has the tone on (tone({variable name}, {frequency});). The passive buzzer is slightly more complicated. It has a small coil inside with a resister. you can tell what comes next.


1

If you want to spread out the multiplexed outputs among the six inputs, what comes to mind is six 8:1 analog multiplexers, one for each Arduino input. Two inputs are unused on each chip. To select the best part, you need to know the output impedances of the sources, the input impedances on the Arduino inputs, and the maximum frequency of interest in the ...


0

The WS28xx series of LED drivers are (were?) made by Worldsemi, but there does not appear to be a datasheet for the WS2813 available on the site (yet). It seems that another company, Shenzen Normand Electronic Co may be the manufacturer. Maybe it is a copy or a clone... The datasheet can be found here. In any case, page 2 states that data at BIN and DIN are ...


2

This is a typical industrial datasheet, in that it's light on the details. The mechanism isn't obvious from the picture (can't tell if it's a pilot valve), but it probably does need a bit of pressure to open. You haven't told us your operating pressure, but somewhere between 0 and 5 psi may be necessary. Next possibility is that your valve is broken, but I'...


0

You probably won’t be able to measure this without extraordinary skills at EMI proofing everything. The arc current rise time will be in excess of 1GHz BW and this means you need RF experience to make a current shunt with 50 Ohm coax and 50 Ohm terminators with shielding and filtering on all I/O lines and semi-rigid or microwave coax. Basically the air ...


1

Adding an MCU to a Ding-Dong chime doorbell The circuit is likely like this currently: simulate this circuit – Schematic created using CircuitLab The Reed relay can be almost any 5-12VDC low current unit such as LittleFuse HE3621A1200. This operates from 12V to 22V without problems, and the 8V supply when rectified would give about 9-10V DC, more ...


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