# Tag Info

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I woud like to add this as a comment but i don't have the 50 credits so far. This topic might be a answer for you Measure resistance accurately with an arduino? To calculate the temperature you can use this formula: Resistance thermometer elements can be supplied which function up to 1000 °C. The relation between temperature and resistance is given by ...

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I searched for the Arduino UNO schematic The relevant part is and it shows that there is indeed a led connected to pin 13

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You can use an external IC that takes care of reading the sensor and then get the result digitally, for example MAX31865 Maybe I could somehow obtain the resistance of PT100 and with some math formula get the temperature? You can find resistance tables in internet , you can create a table in flash and use interpolation to calculate the temperature ...

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You can not connect an RTD directly to an A/D converter. You need to put the RTD into a bridge and use an instrumentation amplifier to develop a larger signal.

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Yes, the only reliable option I have found to avoid packets being split is to use the API mode. There is an Arduino library to help you with that already, xbee-arduino from Andrew Rapp. Don't forget to configure API mode escaped, otherwise the frames will be considered wrong, nothing will be received, and you'll not understand why. On the computer side, the ...

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Per the datasheet, the MB7360 has an RS232 interface, unlike the analog interface in the question you linked. You should be able to easily run 20 meters or more with unshielded cable.

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I've figured out how to program an ATmega on an Arduino board directly from the command line, without using the Arduino IDE and its libraries. I can program it now like any other bare AVR, but with the advantage of an integrated USB ICP programmer. So I am still using the board (which is little more than a crystal, a USB to UART interface and a voltage ...

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Perhaps "actuator" is a mis-translation? I would call the LED an indicator. When debugging a program on a microcontroller, it is often handy to have a LED that know will work to use as an indicator that the program has reached a certain place, or attempted to do some action. Eg: set the LED on when a motor should start, and off when it stops - if the LED ...

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I prefer to program the arduino using the USB interface. You can do this easily with avrdude by passing a command similar to the following: avrdude -v -p atmega328p -c arduino -P /dev/ttyUSB0 -b 57600 -D -U flash:w:blink.hex:i I've found these tutorials helpful to get started: http://hekilledmywire.wordpress.com/2010/12/04/22/#more-22 ...

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To power more LEDs usually requires more current, not more voltage. The ATMega328 microcontroller in a typical Arduino has IO pins which can provide enough current to illuminate an indicator LED - say 20 mA. The total current is about 100 mA. To drive more LEDs or higher powered LEDs you can use a transistor to switch current from the Arduino supply of ...

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In order for the bridge to produce an output between S- and S+ the bridge must become "unbalanced" when weight is applied. So if all 4 load cells produce equally increasing or decreasing resistances when weight is applied the bridge will remain balanced and the output will not change. If the load cells are arranged such that the left and right halves of ...

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The L293 H bridge is a poor choice for a low supply voltage motor controller. From memory, at 1 amp load, the volt drop across the output transistors is about 1.8 volts and this means, from a 5 volt supply, you'll only see about 1.5 volt across the motor. You need to use a H bridge that utilizes MOSFETs as the output transistors and you will probably find ...

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if you plan to read serial data from al APC220 RF antenna with python, you will have to add the line : ser = serial.Serial('/dev/ttyACM1', 19200) ser.setRTS(0) # <------------------- this line solve the problem I found it after a whole day of try-error.

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These devices require (typically) 10-24v to operate reliably due to the onboard regulator. With a supply as low as 5v all sorts of stability issues will occur. Try powering the PIR with 12v connected as its supply. Retain the 10k resistor though as this is performing the open collector level conversion and giving an output that will swing from 0-5v. ...

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I think your wiring arrangement is ok. However, I would bet that one of the half bridges is wired backwards. To determine which one might be wired backwards, I would connect a digital volt meter to the points labelled S+ and S-. I would make a note of the reading with no pressure applied. I would then apply the same known weight to each corner (half ...

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Your diagram doesn't make any sense. As RedGrittyBrick correctly points out (+1) the 4051 selects 1 line (from the 8 possible) using a 3 bit binary input (S1, and 3) and connects the selected analog channel to a common analogue connection marked Z, which is pin 3. There is also a 'not enable, E' input on pin 6. LOW on this input enables the chip. If you ...

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Here's the functional diagram from the 4051 datasheet You need to apply the correct digital signal to S1,S2 and S3 to select the analogue port (one of Y0 to Y7) to be connected to Z. Your diagram is unlabelled, so hard to understand but makes it look like you have S1,S2,S3 tied to GND, which should select Y0. You also need to tie enable to GND (after ...

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Interrupts on the ethernet shield are not supported by stock library. (don't think anyone has gotten it to work). Noting the RF Link is a receiver and will be connected to the RX of the Serial. The Arduino's Serial Library will collected this using interrupts (per byte) into the Serial Buffer, to be read by your application. So as long as the Serial Data ...

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This may be a good place to start, given that the calculator functions themselves won't be that hard. http://forum.arduino.cc/index.php?topic=49654.0 edit: More specifically, this: https://code.google.com/p/tinkerit/wiki/Cantarino

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You can use them together. Both chips can be controlled by the SPI protocol. To answer your question you first need to understand SPI: SPI utilizes 4 data wires. They are usually called MISO, MOSI, SCLK and CS (chip select) in Arduino world. MOSI stands for master out - slave in. MISO is then master in - slave out. You need to connect your devices like ...

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The problem here is all about timing, so let's all get our oscilloscopes out! Basically (and a little over simplified) most standard C flow control statements cannot make timing guarantees on a microcontroller. Hardware based interrupts guarantee the code will begin execution within a fixed number of clock cycles. The Arduino (more specifically, the ...

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How about something like the Raspberry Pi? Apart from running on 5v (not 12v) it looks about right for you. This thread in the Pi Forum includes discussion on using a Pi as part of a mesh network and some details of adapters that do (and don't) work for the task. The Pi already has a built in 3.5mm mini jack for stereo audio out and 10m between nodes ...

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Your NPN power transistor seems to be connected up wrongly. I'd expect something like this ... simulate this circuit – Schematic created using CircuitLab where R1 limits base current and protects P1. $R_1 = 5V - V_{BE(sat)} / I_B(20mA?)$ R2 limits LED current. $R_2 = (18V - V_{LED} )/ I_{LED}$ Q1's collector is connected to the LED's ...

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First do you know if it has been secured ?? If so then its hopeless. Its been 20 years since I last used HC05. Where from my paper copy of the data sheet. It looks like you can likely use its Standalone Bootstrap mode by appling VPP followed by setting PD5 and PD2 low, along with PD3 and PD4 to high. Then release RESET# and the HC05's bootstrap with start ...

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The Hardware SPI module forces the use of the Assigned SS pin on slave mode. The pin schematic shows that it is automatic, and cannot be overwritten, as long as the SPI module is in use. See the ATMega328p data sheet, section 18.2 and 18.3. You need a software SPI implementation.

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The ATmega328p datasheet section 18.3.1 states the Slave Select (SS) pin is always input. where using the SPI in slave with out a SS would likely have issues with sync'ing the first bit of the data. Where if that is not a problem then I would suggest that perhaps a Leonardo would solve your problem. It has 8 PWM's, none on the SPI. Whereas its SPI SS ...

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The SPI has two modes: Arduino Stock Library natively only supports master. Your scenario sounds exactly like SLAVE, in that the other end is driving the Clock. full example You can tie your Ready to the SS(as input) and setup the SPI with the correct mode of phase/polarity. Then set the SPCR as Slave. Enable your Ready and then wait for the 8 bit ...

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A few observations. 1) will your uno be placed so that it can reach all the sensors via bluetooth? 2) why not just add bluetooth to your central server and avoid the time synch wakeup altogether, since the central server will be on all the time. 3) dead reckoning using the timer will eventually drift. You will want them to have your peer to peer network ...

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Most likely no, in any case not in software. Displays like this are usually single color, some are dual color, at most. The colors are physical properties of the LEDs and can't be changed. If you want arbitrary colors you need a red-green-blue triplet of LEDs for each segment, and I've never seen any of those. Like I said some displays are dual color, for ...

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"Myo" is in preorder right now; it will have an SDK but I don't know whether you can use it with an Arduino. https://www.thalmic.com/en/myo/

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Add these steps to your algorithm: 0. Prepare first bit of data ... 3. Use external interrupt on rising edge to output prepared bit and put next bit into your bit holder variable. Count outputted bits. * Step 3 will be automatically repeated 16 times (external device will trigger it). 4. When bit counter reaches 16, disable ext interrupt and set ready line ...

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Yes that error is because there is no communication between the the board and your computer. Unfortunately this is difficult to debug as there is almost an infinite number of issues that can cause this. All I can recommended is this: You need to troubleshoot both ends: On the board: 1) Check your voltages. Are they correct? If possible do so with an ...

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A timer in normal, Fast PWM, or CTC mode counts directly from BOTTOM to TOP if no external influence is applied. As it passes each OC value it emits an interrupt and/or frobs a pin, as it is configured to do. Each OC value is only crossed once, which means that all OCs for the same timer all run at the same frequency. They can be configured to have ...

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The timer module allows you to generate multiple outputs with different duty cycles, but they all will have the same fundamental frequency. If you want to generate different frequencies, you will need to use a different method. There are two main ways to do this. First method is to use three timers, each operating at a different frequency. If you are ...

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The device you've come across (presumably from an old PC motherboard or similar?) is likely to be a poor choice for interfacing to an Arduino from a practical point of view. It's designed to interface to a microprocessor with an external data bus and after a quick look at the data sheet you'd need to use 8 I/O lines for address / data information and at ...

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Arduino The name Arduino belongs to the Italian company who first made the product. This is a commercial company and the name Arduino cannot legally be used by other makers - though they are allowed to claim products are Arduino-compatible. However most people tend to use the term in a much broader way to refer to all the things that are in some way ...

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You should not assume that it's safe. Input protection diodes may cause the IC to become powered when inputs are applied. If you switch to a device family that supports "level 1 live insertion", what Texas Instruments calls "Ioff", then you can apply logic levels to the inputs since they will be high-impedance when VCC is not applied. TI logic families that ...

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Yes you can, jus three things: Try to use the main loop to do all you need, trying to programm a cyclic executive and use the interrupts only to activate flags or read ADC values. You can achive this by setting times for each task, for example, read the ADC every 5ms, Set the LEDs every 10ms, etc. In some Atmel devices like Atmega16, you need to reset ...

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The cable would be about a metre in length The current is about 40mA The code is currently running about 50,000 times per second (I think), but it doesn't really need to if that's going to affect the cable choice; 1,000 times per second would be fine The shift registers are both 74HC165 Based on that, it would be fine. RJ45 connectors, ...

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In addition to the other points noted, the protection diodes D2,D4 ought to connect to GND not the PWM transistor collector, otherwise they simply pull the collector -ve instead of protecting the bridge transistors.

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I see three issues with your code: Variable volatility and scope The variables below will get corrupted due to the fact that you define them only in the ISR. But you clearly want to retain their value between interrupts. Make the following variables volatile and define them globally, not in the ISR: uint8_t lastState; uint32_t startTime[8]; Accurate ...

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I noted two things, the first is that you don't control the base currents with resistors. The second is that placing the PWM transistor at the bottom means you have to use higher switching voltages which may or may not be a problem, if you are switching a couple of amps (likely) it probably would be. I would put the PWM transistor as a PNP at the top and ...

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With all due respect to David Brin (I happen to like his books a lot; I'm not qualified to judge how good he is as an astrophysicist), he's neither a programmer or an educator. I was around and coding in the early days of PCs, and I wrote a fair amount of BASIC code. And I've been writing code professionally since then. The reason we used BASIC back then ...

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No, this circuit isn't even close to correct. Unless V+ is limited about 1.5 Volts or so, it will rapidly vanish into a puff of smoke. On the left side, both trasistors will always be on if the the supply is more than about 1.5 V. These transistors are not voltage-operated. The base voltages will be around 700 mV from the base when on. Put another way, ...

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image selected at random from somewhere in the intertubes. ditto Some people prefer MOSFETs ditto See also prior art For a bigger motor you might use a BJT to turn on a heftier MOSFET ditto Important notes Ensure you use a switching device that can comfortably handle more than whatever maximum current the specific motor will need. It is good ...

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Coming in late, but this question wouldn't be complete without considering a no electonics, no moving parts solution (if such is allowed on StackEX/Electical-Engineering): If you're willing to hand fill a bottle occasionally, pick a suitably large bottle to fit your preference for "occasionally", arrange to support it inverted in the dish with its mouth at ...

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You can control about 6 low voltage motors under 5v using this code and you adjust the timing for each of them by changing the code, or you can use the led as an output to signal 6 other relay for whatever timing you want. For higher power you might want another power source beside that, pretty simple to do it this way, hope it works for you. /* Switch ...

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The main problem I had seems to be that in my breadboard setup the connection to 12V is not very solid and generates in insane amount of noise and the capacitors on the Arduino are potent enough to handle that. What I will also be doing is using a 5V regulator rated for 35V input before the 3.3V volt one, this will also allow me to power the h bridge from 5V ...

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The L293 and most variations are 4.5v minimum VCC. That is why you are not getting the Stepper motors to run. The TS1084 is a Linear Regulator with MAX input of 12v. You are wasting (VIN - VOUT) * IOUT in heat. That's (12v - 3.3v) or (8.7v) * IOut. Even if just half an amp, that's 8.7v * 0.5A or 4.35 Watts! of energy into heat. Tj = (Pd · θJa) + Ta ( 4.3W ...

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The problem is that you do not link to the ones your reseller sells. The term shield and module are thrown around a lot, and in the case of some of the higher tech boards, arn't fairly uniform. In this specific case, you really need to be sure before you waste your money. Look below for many of the combinations you can find. Since you arn't in the US, I'm ...

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