Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [timer]

Circuit to generate a signal a specific time after a trigger event. The timing can be defined by an RC time constant, or by clock pulses from an oscillator.

0
votes
1answer
44 views

IC 558 Quad timer chip, single timer in monostable mode

I'm looking at the datasheet / Application Notes for the 558 Quad Timer. Specifically, Figure 5.a Monostable Operation (One Shot) I want to drive a LED with the output. I see from the notes on data ...
0
votes
3answers
97 views

1PPS vs high resolution timer in CPU

We need to use 1PPS (pulse-per second) in our standalone system which is based on arm processor, and has cameras input. The 1PPS is implemented with GPIO which is injecting an interrupt (low to high)...
0
votes
0answers
58 views

STM32CubeMX for UART example

I am trying to run the example given in CubeMX document UM1718, Tutorial 4 - Example of UART communications with an STM32L053xx Nucleo board.. page 230. I wonder what is the purpose of using TIM2 in ...
2
votes
4answers
74 views

Will this 555 circuit prevent a car from disconnecting power to the radio when starting?

To start with I'm a little rusty with electronics, I haven't done much in 20 years and it was only a hobby back then. In my car I have a head unit with a touch screen which relies on software to run ...
1
vote
0answers
100 views

Please help me understand this bjt set up works

This is part of an automotive timer (NOT a 555!) that we have at work. Because I'm extremely bored I'm challenging myself to understand how this one operates. I've spent about 1.5 weeks with tutorials,...
1
vote
1answer
49 views

STM32F3 - diffrence between PWM1 and PWM2

Can anyone explain to me wht is the difference between PWM1 and PWM2 in STM32F3 timer configuration? It is mentioned frequently in documentation, however I can't find the difference between these two ...
-2
votes
1answer
62 views

STM32 GUI for Timers [closed]

The CubeMX for STM32 MCUs gives an easy graphical interface to configure the Clock tree. I wonder if there is similar GUI tool for configuring the peripherals specially the advance timers TIMER 1 and ...
6
votes
1answer
612 views

Inaccurate timer interrupt STM32

I wrote a simple program to toggle an LED on and off using the TIM1 interrupt on an STM32F0 discovery board. CLK Freq = 48MHz Prescalar = 48000 Auto Reload Register = 1000 Using the following ...
0
votes
1answer
45 views

STM32F091 timer as a prescaler for another timer

I would like to chain two 16-Bit timers to each other to make a 32Bit timer. Just like the example in the datasheet [RM0091 figure 147 page 429] but with different timers. I found these two sites: ...
1
vote
0answers
37 views

Simple coountdown timer IC that is independant of supply voltage

I'm designing a shutdown circuit that switches off a SMPS regulator after a 10 second time interval. This is a battery powered application and the battery voltage could be anywhere between 7-15V. I'...
0
votes
0answers
38 views

Inverted 555 Monostable Timer With a Sustained Input

I am using a 555 Timer to control a motor for a science team project. I have to make a Rube Goldberg-like machine and I am not allowed to use Arduinos or Raspberry Pis. However I need to trigger the ...
0
votes
1answer
76 views

555 Timer Giving Unexpected Output (Astable Multivibrator)

I am using this design with the only exception that C2 is 150nF to change timing slightly. When I plug in the circuit and attach an LED across GND and pin 3 output the LED is static on. However, on ...
0
votes
2answers
62 views

555 as slow PWM driver

I would like a slow PWM output, driving a relay turning an AC heating element on and off. I desire a period time of around 10s. What is a realistic upper period time limit for a PWM circuit like the ...
1
vote
0answers
45 views

556 circuit not working

I just got my 556 timers and I wired it up just like the 555 but now: it flashes one HighTime and stays off then... I used this calculator and basic diagram: http://www.ohmslawcalculator.com/555-...
0
votes
0answers
23 views

Problem with using Timer Counter interrupt on Atmel ARM

I'm using an ATSAM4E16C microcontroller and i need to get a 1 millisecond tick. I want to implement this using the timer counter module to trigger an interrupt. The clock frequency is 96 MHz, so using ...
0
votes
1answer
73 views

Self cancelling indicator project. Help needed

I am embarking on a new project to design a circuit for an automatic vehicle signal actuator. Outline of the project is this: The problem: I have a car that has indicators operating on a standard ...
0
votes
1answer
56 views

How can I use the component CD4538 or a 555 timer on Multisim?

How can I use the component CD4538 or a 555 timer on Multisim for a delay of 1 second ? I want both of the nor gates to be 1 for roughly 1 second when the output of the op-amps is either 01 or 10.
0
votes
2answers
127 views

How to generate a single pulse using RC circuit from a fixed DC supply without any controller, timer or delay IC?

I have a DC supply (5 V) to turn some circuit on and in that circuit there is a module which uses a specific mechanism (i.e. a 2 seconds width high pulse) to turn on (even if a supply is connected, ...
0
votes
0answers
13 views

Checking HM-TRP radio adapter for initial data

I have several HM-TRP radio adapters (consisting of the HM-TRP chip with a female header connected to it) of the same version. I tested it in a mini circuit where the PC does direct I/O with the HM-...
0
votes
1answer
54 views

Reading STM32F timer value

I am trying to implement a hardware timer for STM32F and read the value from it. So far, this is my implementation: ...
0
votes
3answers
78 views

Need help understanding RC discharging through a transistor in a timer

Once I push and release a pushbutton I want a LED to light for say 10 seconds. I found a design for this on the web and tried it out: What I observed on the breadboard was that the LED lighted for at ...
0
votes
1answer
34 views

Dusk dawn motor driver with polarity reversal

I'm trying to accomplish this. When a dusk dawn switch is on, drive a small DC motor for a few seconds and then stop. when the dusk dawn switch is turned back off, then turn a small DC motor THE ...
0
votes
2answers
152 views

Is the circuit in this answer wrong?

In the Q/A link below, the circuit in the answer seems to be wrong to me. Answer to "How to gradually light up an LED?" Circuit: simulate this circuit – Schematic created using CircuitLab In ...
0
votes
1answer
66 views

Six monthly service timer with indicator

I have been requested to look at a project. The first half of the project is complete, but I am struggling with the second half of the requested specification. For the second half of the project, I ...
0
votes
1answer
44 views

Why is the potentiometer setup in this configuration in this 555 circuit

I just started learning about chips and signals using the book Make: Electronics, in one of the circuits, used to generate a pulse in Monostable mode a potentiometer is used to vary the pulse length....
3
votes
1answer
48 views

Timer activated by Reed on AC solenoid

Let me start by saying thank you for taking the time to read this - I really appreciate it! To the point: I am trying to create a 2-digit timer that resets and then starts at the activation of an ...
0
votes
1answer
23 views

Timer Interrupt Setup in ThreadX

We're trying to set up ThreadX for the first time and we're trying to understand all the timer settings that. Although there are basically two constants that we need to set, they are not really clear ...
0
votes
0answers
22 views

Can standard 8051 timer 1 and timer 0 be available to programmer when serial mode 1 is used?

The micro is an AT89C4051. It allows two timers and a serial port interrupt. Currently, I set things up so that if any kind of data is received on the serial port, it just is loaded into memory by ...
2
votes
1answer
176 views

STM32L0 - Delay in microseconds

I am using a B-L072Z-LRWAN1 board (which has a STM32L072 MCU) and I want to get data from a DHT11 sensor. To achieve this, I need a microseconds delay which I am not able to obtain. The libraries ...
0
votes
1answer
52 views

How to turn off 555 Timer for a period of time after Vout signal passes through

I have a single-shot 555 Timer. After triggering, output goes high for a period of time. What I would like to do now: After Vout goes high and then low again, I want to disable the 555 timer for a ...
0
votes
1answer
40 views

STM32F030(K6) Systick not triggering (BOOT0 problem)

I'm trying to write a simple program for a STM32F030K6T6 microcontroller. The problem I am facing is the more common "Systick is not working" problem. The code is generated using Cube32MX (Firmware 1....
0
votes
1answer
95 views

COMP2 to trigger One-Pulse mode on STM32L1

I am trying to use the output of COMP2 to trigger the One-Pulse mode of a timer (in my example TIM4, but it's quite flexible if it needs to change to another timer) on the STM32L1 series. In the ...
6
votes
3answers
1k views

Difference between internal and external oscillator for a microcontroller?

I am a beginner with respect to microcontrollers, so I just want to ask is there two option for choosing the frequency of the microcontroller: to be internal or external? If there is internal ...
0
votes
1answer
51 views

Open and Close Circuit automatically (Automate Push Button)

I have a simple circuit board with a push button on it. I just want to automate the pressing action every 0.2 sec or so. The push button has two terminals underneath and I understand that I should ...
1
vote
0answers
81 views

strange array values (C, psoc, usbuart)

I am still fairly new to programming, so I'm sorry in advance if my terminology/formatting isn't up to scratch. I am currently working on an element of a musical instrument that will allow me to ...
2
votes
2answers
58 views

how do I implement a start timer in a digital circuit

In vhdl, I know how to code a start timer behavorially. However, if I have to implement such a counter to start based on a trigger, how could I implement such a counter? My trigger is another signal ...
0
votes
1answer
81 views

555 Timer circuit analysis

I am trying to analyse a 555 based timer circuit: My current understanding of the circuit is that the output is changed by the voltage at pins 2/6 (let's call it V). If V drops below 1/3 Vcc, output ...
1
vote
1answer
134 views

Generating 1 second with avr and timer 0 for Atmega32A

dears: we have to Generate 1 second with atmega32A and mikrobasic software. so I have configured timer 0 and avr with this way: ...
0
votes
1answer
57 views

How is a long timer implemented?

Given the following constraints: ~20% accuracy or better Vcc=5V Input is the falling edge of a TTL signal Output can be TTL or the input to a Schmitt trigger Time between 1-60min adjustable via pot ...
1
vote
1answer
109 views

Expected behavior of 555 timer in monostable mode

While assembling the 555 timer based circuit below I noticed that 1) the intended delay on pin 3 only works if the switch on pin 2 is closed before attaching the circuit to the 9V power supply. ...
0
votes
2answers
183 views

Using Timer 555 to obtain a frequency multiplier

How can I use a timer 555 IC to obtain a frequency multiplier? I made a frequency divider by using a timer in monostable mode but a multiplier looked difficult. Can somebody tell how can I design a ...
1
vote
1answer
46 views

What's the name of a timeout relay which won't re-trigger if it times out?

I would like to replace the relay which triggers a water pump, with a relay which times out after, say, 10 minutes. And if it times out, it stays locked out until reset. Needs to be 230v AC on both ...
1
vote
0answers
132 views

STM32F407 - how do I run one motor at a time? Why do they ignore delays..?

I'm a newbie. I'm using an STM32F407 discovery board, and I want to control 6 stepper motors using PWM, especially OPM(One Pulse Mode). Till now I've made 3 stepper motors work using Timer 8 (CH1, ...
0
votes
1answer
535 views

STM32 Logic level high and low thresholds

I am scratching my head to find what are the minimum voltage for registering a low digital signal and maximum voltage for registering a high digital signal when I configure GPIO pins of STM32 (I am ...
4
votes
1answer
92 views

How to avoid this voltage when I turn on the circuit?

What I want to do is an Delay ON, but when I press the switch this voltage pass for a brief moment and turns the led on for a moment. How can I avoid this? Should I put the switch somewhere else? ...
2
votes
1answer
114 views

Why can't I route the same signal to multiple pins on an STM32F407?

I have a periodic signal which I want to use as a trigger to two timers - TIM8 and TIM2. When the signal goes high, TIM8 should start running and TIM2 will be clocked once. TIM2 will be configured in ...
1
vote
2answers
66 views

Hold Pushbutton for soft latch after X seconds

What I'm trying to achieve is have a momentary push button that must be held for say 5 seconds before latching on permanently. But the button must be held for entire duration or else timer will reset....
0
votes
0answers
44 views

Suggestions for switching 800VDC converter on/off

I'm stress testing(turning them on-off with load every 300 seconds for 1-2 weeks) the components that we are willing to use. have tested several battery chargers with AC input with using a timer relay ...
0
votes
0answers
22 views

HM-TRP radio module works at 56K data speed but only in delayed chunks

I created the following setup: I created one circuit in which the PC connects to an HM-TRP radio module via a max232 DIP IC. This circuit for the test is the master to all devices and sends a 16 byte ...
0
votes
1answer
93 views

Led as an input photodiode [Arduino AVR]

I’m trying to use a LED as a light sensor(input) connected to a Arduino Nano. I connected the led with the Anode at digital pin 8 (PB0) with a resistance of 56 Ohm and the Cathode at an analog pin A0 (...