Can you use a picaxe 08m or 14m to make a PWM fan controller..
Short answer: yes.
I see you have made a start, and found a pwm fan controller circuit.
See picaxe_manual2.pdf for pwm & pwmout commands, and note the pin used, the command format, etc...
Hint: *Always* search the 3 picaxe manuals first.
See picaxe_manual3.pdf - see "Output Devices 5 - Solar & DC “Toy” Motors" (not that it's much)
(I downloaded the latest manuals just for this search, and looked hard, and found fa myself)
Hint: Tell the forum what attempts you have made. Forum is more for correcting than doing *smile*
A similar random circuit to the one you found:
http://www.discovercircuits.com/DJ-Circuits/images/SIMPLEPWM2.jpg
(from page
http://www.whatcircuits.com/motor-control-circuits/555-timer-forms-simple-pwm-motor-controller/ )
Look at lots of simple small motor pwm control circuits, they're common for other micros too, so many of the circuits for, say, the basic stamp, will be a good start for use with the picaxe. Google is your friend.
Looking at search results will help you refine your search terms within the forum, and elsewhere.
On Stans site:
http://picaxe.orconhosting.net.nz/
Look for his May 2003 Silicon Chip article offering (worth starting with)
"May - Motor controller /motorpwm.bas"
Would a (polytech) library perhaps have that issue around where you are?
The following link is a fan control project that only turns fan on or off depending on temperature, but gives an idea of the next step in completing your design.
http://www.picaxe.us/AV-fan.html (Cct:
http://www.picaxe.us/images/AV-fan-small.png )
Oh, and another circuit, as an example of a fully worked-out design.
http://www.siliconchip.com.au/cms/A_111001/article.html - 12V Speed Controller/Lamp Dimmer
Hope these are of some use to help you move forward.
A common difficulty is knowing which of many directions to answer in, which requires more info from you.
Q: Is there a particular fan you want to control? (Important for suitable circuit design) Or is any small fan a good start for you?
Q: What is your overall goal? Is it educational, or a particular task you have in mind? May I stress that You need the forum to know this.
Your turn