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mabauti said:without using 555/PICs and using XTALs preferably.
any ideas?
newelltech said:Use the power line 50/60 Hz. This frequency is kept very accurate over the long term because so many clocks use it. Just use a small transformer, hard limit the AC to form a digital clock and count it up to 36000 with a single 16 bit counter IC. Just a couple of parts and some resistors, caps and a diode.
It's easier to use than, say, gravity, the boiling point of water or eeeeeeeeeeeeeeeeee 8O .
diagram ? ; I couldn't find a 32Khz Xtal (I'll keep searching) Is there any way using a 2MHz XTal?you start with a crystal oscillator such as 32 kHz. Tnen divide down by the proper amount to get a ten minute period.
Good idea, but I still can't find a 28Khz Xtal (as above : I'll keep searching for it)I would use a 28KHz crystal oscillator. That should get you pretty close to 10 min. pulse generation.
There's not that part in my city, I will take in account that anyway.You may consider to use RTC module, e.g. BQ4850 from TI.
Yep, but I want to keep my circuit with a few components.Use a watch crystal, 32.768kHz and divide that by 2^15 to get 1 second. Then divide that by 600 to get 10 minutes.
My goal is to use a battery with my circuit.Use the power line 50/60 Hz. This frequency is kept very accurate
low 1
pause 100
loop1:
high 1 ' output 1 goes high ..
for b1 = 1 to 10 ‘ 10 loops ..
pause 60000 ‘ wait 60 seconds ..
next b1
low 1 ' output 1 goes low ..
pause 100
goto loop1
Would u please advise how accurate is the method you proposed to generate a 10-min pulse? Thanks.IanP said:Much, much easier, and much much smaller, as far as number of components is concerned, will be to use small microcontroller such as for example PICAXE-18 ..
With 4MHz crystal the code required to generate 10min pulse may look like this:
Code:low 1 pause 100 loop1: high 1 ' output 1 goes high .. for b1 = 1 to 10 ‘ 10 loops .. pause 60000 ‘ wait 60 seconds .. next b1 low 1 ' output 1 goes low .. pause 100 goto loop1
http://www.rev-ed.co.uk/docs/picaxe_manual1.pdf
Any other option must include crystal, oscillator, frequency divider and some additional logic, that's why I do think the "microcontroller" option is so tempting ..
Regards,
IanP
low 1
pause 100
loop1:
high 1 ' output 1 goes high ..
pause 60000 ‘ 10 loops ..
pause 60000 ‘ wait 60 seconds ..
pause 60000
pause 60000
pause 60000
pause 60000
pause 60000
pause 60000
pause 60000
pause 59999
low 1 ' output 1 goes low ..
pause 100
goto loop1
OK 555 will not be precise for 10mn timemabauti said:without using 555/PICs and using XTALs preferably.
any ideas?
To clarify, mabauti, you have placed the following restrictions on your pulse generator:mabauti said:without using 555/PICs and using XTALs preferably.