What would you guess the accuracy would be by doing it that way?

±20%

 

Hum i don't know if that is better than a 555 or not..lol what about if a Crystal was used? What would be the accuracy?

 

Hum i don't know if that is better than a 555 or not..lol what about if a Crystal was used? What would be the accuracy?

A 555 is better (about ±10%) but a crystal would give you ±20ppm

 

A 555 is better (about ±10%) but a crystal would give you ±20ppm

20ppm? not sure what you mean there. if there is a web site link to a 4060 15 min timer using a crystal that is trigger (starts the timer) with a logic high. once the 15 min time is up it send a logic high. please post that link. i will do some testing

 

20ppm? not sure what you mean there. if there is a web site link to a 4060 15 min timer using a crystal that is trigger (starts the timer) with a logic high. once the 15 min time is up it send a logic high. please post that link. i will do some testing

ppm = parts per million. You'll need more than 14 stages of division to get to 15 minutes from any available crystal. Even with the 4521 and a 32768Hz crystal (the lowest frequency available) you would only get 256 seconds when you need 900.

 

ppm = parts per million. You'll need more than 14 stages of division to get to 15 minutes from any available crystal. Even with the 4521 and a 32768Hz crystal (the lowest frequency available) you would only get 256 seconds when you need 900.

ahh ok well i may have to uses a 555 then

 

or i learn how to program a PIC chip. i would assume that would be able to do that

 

or i learn how to program a PIC chip. i would assume that would be able to do that

. . or learn how to cascade dividers, and divide by numbers other than powers of two. Or count mains cycles - that will give you better than 1% accuracy (unless you are running off a generator) Use a pair of 40103s to divide by 150 twice, then divide by two.

If you decide to learn how to program microcontrollers, will it be a skill you will use again? If so, it's well worth the effort, but it may take you longer before you have a working timer.

 

to program chips you need two more things software (IDE+compiler) and hardware (programmer).

most MCUs have free software option.

about the hardware... for PICs you need something like PicKit.

this is one of the nice things of Arduinos and similar - they have this part built in.
You just connect it to USB and you are good.

 

. . or learn how to cascade dividers, and divide by numbers other than powers of two. Or count mains cycles - that will give you better than 1% accuracy (unless you are running off a generator) Use a pair of 40103s to divide by 150 twice, then divide by two.

If you decide to learn how to program microcontrollers, will it be a skill you will use again? If so, it's well worth the effort, but it may take you longer before you have a working timer.

Unfortunately, learning how to cascade dividers, pic programming, etc. would take too long to get a working circuit I need it asap. I will play around with 555 timers and see what I can come up with. Thanks for the help

 

to program chips you need two more things software (IDE+compiler) and hardware (programmer).

most MCUs have free software option.

about the hardware... for PICs you need something like PicKit.

this is one of the nice things of Arduinos and similar - they have this part built in.
You just connect it to USB and you are good.

ya there got to be an easy way to do this programming is there chip out there that program with BASIC

10 print "hi"
20 goto 10

lol

 

ya there got to be an easy way to do this programming is there chip out there that program with BASIC

10 print "hi"
20 goto 10

lol

There was once. It was a Microchip PIC16C55 with a compiler. I don't know if it still exists.

 

not much to code in post #25.
only two subroutines. first one is executed only once when chip is powered.
the second one runs continuously.

since one pin can potentially have many different functions (digital input, digital output, analog input, PWM, ...) program is needed to configure each pin. that is what first part is for. it tells which pins are used and how.

the second part simply runs delays and controls the IO.

 

not much to code in post #25.
only two subroutines. first one is executed only once when chip is powered.
the second one runs continuously.

since one pin can potentially have many different functions (digital input, digital output, analog input, PWM, ...) program is needed to configure each pin. that is what first part is for. it tells which pins are used and how.

the second part simply runs delays and controls the IO.

yes i notice that problem is i don't know how to code so any tweaking to the code i won't be able to do

 

There was once. It was a Microchip PIC16C55 with a compiler. I don't know if it still exists.

wow i didn't know that i may have to check into that

 

https://wilke.de/en/embedded-computer/details/products/basic-tiger-multitasking-computer.html

 

wow i didn't know that i may have to check into that

I have and use PICbasic pro. I think the non pro version is $99.00. basic for PIC
------------------------------
Mfr. Model MIL72ESTUZH-120
Timer This link is to a timer that I think you can program. I had a box full of them. I sold most but probably have 4 or 5 left.
With a flip of a switch you set on/off for every 15 minutes of the day.

 

https://wilke.de/en/embedded-computer/details/products/basic-tiger-multitasking-computer.html

is that code for that?

 

you got arthritis or keyboard does not work?
https://wilke.de/en/service-center/download-center/basic-tiger-handbuecher.html
https://wilke.de/uploads/media/TEP_50e.pdf

 

you got arthritis or keyboard does not work?
https://wilke.de/en/service-center/download-center/basic-tiger-handbuecher.html
https://wilke.de/uploads/media/TEP_50e.pdf

View attachment 327684

huh? what you mean?