Or you could do it with about $5 worth of CMOS IC devices and ZERO invested in programming devices, and if you needed to replace a damaged part in ten years it would still be available and you would not need to program it.

I have this circuit breadboarded, tested and all drawn up ready to go if the TS is interested. Whether it could be constructed on a PCB any smaller than an Arduino Nano though is unlikely, even using SOIC packages and surface mount components.

 

i am open to all ideas please post schematic, I will build and test the circuit

 

Hi tim,
Why does it have to be as small a possible???
E

 

Because I want to fit in into the same project box that has the other device in it. a couple of DIP IC and a few components would be ok.

 

You are not getting it you can pull the chip and program a attiny leave the chip in and burn bootloader
the UNO as a programmer. there dirt cheap or get one of these
https://www.amazon.com/dp/B09921SC7...&s=pc&sp_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWw&th=1

20 dollar programmer
Or the UNO less then 10 dollars

#define ledPin 13  // Pin connected to the LED

unsigned long previousMillis = 0; // Variable to store the last time LED was updated
const long interval = 1000; // Interval at which to blink (milliseconds)
const long timerInterval = 1 * 60 * 1000; // 15 minutes in milliseconds 1 * 60 *

//bool ledState = LOW; // Initialize LED state

void setup() {
  pinMode(ledPin, OUTPUT); // Initialize the LED pin as an output
}

void loop() {
   digitalWrite(ledPin,LOW );
  unsigned long currentMillis = millis(); // Get the current time

  if (currentMillis - previousMillis >= timerInterval) {
    // It's time to toggle the LED
    previousMillis = currentMillis;
    digitalWrite(ledPin,HIGH);
    delay(interval); // Wait for 1 second
    digitalWrite(ledPin,LOW ); // Toggle the LED
  
  }
}

That code works I just tried it out

Also, I was thinking anyway to add a trigger pin ( logic high) once that is triggered that would start the timer? And has this function to be on a switch? Meaning if this switch is on only work with a trigger. if switch is off then timer every 15 mins? For that matter, have another pin monitor if it's logic high no timer would start ( trigger or standard timer) intill that pin is a logic low.

 

hi tim,
It would help your helpers if we had an idea of the volume/space available for the project?
E
@timtim1234

 

The attiny not going to be a easy part to program the new ide has problems with broken libraries

 

The attiny not going to be a easy part to program the new ide has problems with broken libbers

hummm can you explain more what you mean?..lol sorry programming is new to me

 

Sorry I've not responded sooner, been a little busy with other things. Anyway, here is the circuit I came up with. Nothing revolutionary, flip flop U3A produces the 1 second output pulse, once every 15 minutes, positive or negative going depending on whether Q or /Q is used. Timing was using an electrolytic capacitor, so R5 could need adjusting to get it spot on! U3B produces the 15 minute high/low cycle.
To test, just fitting the diode to Q4 gives a complete cycle every 8 seconds.
The reset switch is High to reset, could be a momentary or toggle, or a fairly high current logic pulse (due to R4 needing to pull up against possibly up to 4 low outputs of the CD4020.



EDIT: Image edited for incorrect wire.

 

Also, I was thinking anyway to add a trigger pin ( logic high) once that is triggered that would start the timer? And has this function to be on a switch? Meaning if this switch is on only work with a trigger. if switch is off then timer every 15 mins? For that matter, have another pin monitor if it's logic high no timer would start ( trigger or standard timer) intill that pin is a logic low.

This is the best argument you could make for using a microcontroller. The new functions could be added mostly in software. If you had built a hardware version and wanted to make this change it would be back to drawing board.

 

Hi sarah,
From what TS is posting, free installation space is at premium, I have asked what free volume space dimensions are available, so far no answer.
Perhaps you may have more luck getting this information.
E

 

Consider that ALL of the components used in the circuit of post #149 have been available for at least 20 years, and will continue to be available for quite a while yet. Then consider that no expense for programming would be required and that every aspect of the circuit can be easily understood by those with a bit of electronics knowledge. And if one is wanting to learn, the logic functions can be understood.

 

Hi

I have be playing around with 555 timers and I have on order cd4060. I am trying to make a timer that goes for one second a logic high or low ( selectable with switch) every 15 mins. I notice that 555 is not good for long time cycles. So I think a cd4060 would be better for this.

Sorry I don't want to mess around with MC, PIC, etc I don't want to learn programming.

Thanks

Consider the LTC6991 Slowest time is 29.1uH

 

The attiny 85 you have to add cores to the Arduino ide there libraries that tell the ide about the chip pins how much code you add to it
the ide is now 2.3 .2
so you have to add the right ones to the Ide plus programming using the arduino as isp doesn't work from the load button in the IDE
you have to use ctrl shift u to load the code into the attiny
And there are lots libraries out there you pick the wrong one and the code i posted will never use millis

If you want use the attiny don't install the latest ide use one of the older ones like 1.6 to 1.8

 

Keep it simple!

The following will do what you want. Download the Arduino IDE, buy a Nano (or any other Arduino-compatible MCU), and spend a couple hours (or less) running the code to see it work. For testing, in the code below you could change the 899 to 59 and see a 1-second pulse every minute on pin 8 (scope or DMM).

• Download and install the Arduino IDE on your PC: https://www.arduino.cc/en/software
• Buy a “Nano” microcontroller (contains the program loader)
• https://www.amazon.com/LAFVIN-Board-ATmega328P-Micro-Controller-Arduino/dp/B07G99NNXL/ref=sr_1_2_sspa?crid=2DRLI47YMVCCY&dib=eyJ2IjoiMSJ9.8OxbH_5j-H08THJaE3TLwRgWB1jyYqARwwE-oC7y63gWLRmz3o6GDA-ESzCftrzLZnR11wGbTNQRjyyuDXYNeXcJ18Gqg5JWcYcDAlpf1kulPIBK9VucFtMUFp-fBK34T2c6mkbSgtafowLy2TLZBiECjY0iAJ8fN1xELbkAdfMENscKToR4PAw_mO_GcaxPhFb_TS9Q1iJQux79Dd3pyJhHWr7lPL2lUsQN__qma2g.6CGpRxekurh5piyoJ6CL1jw9gd225dS3pOQr4ffXXbM&dib_tag=se&keywords=nano+arduino&qid=1722015085&sprefix=nano+arduino,aps,152&sr=8-2-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1
• Plug the Nano into your PC USB port using a USB cable.
• Run the Arduino IDE on your computer.
• Copy/paste the following code (from post #86 in this thread) into the Arduino IDE screen:

Mod: added Code Tags

int pin = 8; // pin 8, which is to be set high or low

int n = 0; // declare “n” as an integer

void setup() {

pinMode(pin,OUTPUT); // set “pin” to be an output pin

}

void loop() { // this “loop” section runs repeatedly forever

for (n=0;n<899;n++){ // let 899 seconds elapse

delay(1000); // 1000 milliseconds = 1 second

}

digitalWrite(pin, HIGH); // set “pin” to logic high (5V)

delay(1000); // wait 1000 milliseconds (1 second)

digitalWrite(pin,LOW); // set “pin” to logic low (0V)

} // jump back to void loop() and repeat

• Click the “Upload” button (the forward arrow in the IDE upper blue taskbar)
• IDE compiles and uploads the code to the Nano

 

that was suggested many times but TS is not encouraged. if i recall delay() accepts long integer as parameter so it should be possible to make the 15min delay without loop.

 

The ttiny 85 not really a chip for the first time user the nano be the best bet
15min delay without loop. with delay() it said you use long integers

 

that was suggested many times but TS is not encouraged. if i recall delay() accepts long integer as parameter so it should be possible to make the 15min delay without loop.

I did buy the ebay one. i posted the link

 

Hi sarah,
From what TS is posting, free installation space is at premium, I have asked what free volume space dimensions are available, so far no answer.
Perhaps you may have more luck getting this information.
E

sorry didn't see that post its bout 2x3 box

 

sorry sometimes its hard to keep up with the posts they seems to come in faster then i can keep up

i also asked about tweaking the code? i will repost what i asked too

Also, I was thinking anyway to add a trigger pin ( logic high) once that is triggered that would start the timer? And has this function to be on a switch? Meaning if this switch is on only work with a trigger. if switch is off then timer every 15 mins? For that matter, have another pin monitor if it's logic high no timer would start ( trigger or standard timer) intill that pin is a logic low.

the code above for a ttiny85