Timer

Hi, Everyone
My project is only to start a timer on esp8266 module, no wifi. This timer would be picked on power on to the module and never end till power off to the module.
Thank you in advance.
Ray

The millis() function does exactly what you describe. It counts the number of milliseconds since power on or reset. Job done, but you have not explained what you want to do with the timer

OK.
Thank you for your response.
Here is the project

1- When the furnace thermostat makes contact, I want a fan to start to make an updraft on a chimney but not the furnace blower.

and

2- After 5 minutes of this updraft, I want the furnace blower to start and never stop till when the thermostat open the contact to stop the furnace.

You can use millis() timing to do that

See Using millis() for timing. A beginners guide, Several things at the same time and the BlinkWithoutDelay example in the IDE for some ideas

Thank you very much UKHeliBob. It's exactly what I need.
Just one thing. I know how to start the timer with a delay of 5 minutes, but I don't want it to stop the timer until I remove de voltage from de board.???

You don't have to stop the timer. Your basic code flow is

  1. Power on
  2. Turn on updraft fan
  3. wait 5 minutes
  4. Turn on furnace blower
  5. do nothing until power is cut

And, since this is such a simple task, you could do it with a ATTinyXX board cheaper than an ESP8266.

I don't want it to stop the timer until I remove de voltage from de board.

millis() will keep running all the time the board is powered. It is up to you when and if you take any notice of its value increasing

I thank you, everybody that answered my question.
that will be all.