Search found 1636 matches

by ahull
Sat Nov 25, 2017 2:32 am
Forum: General discussion
Topic: OverClock. at Runtime ~90MHz
Replies: 25
Views: 260

Re: OverClock. at Runtime ~90MHz

It seems USB supports suspending.. so you could in theory, boot, enumerate USB, suspend, run at crazy speed, go back to normal speed, un-suspend, say something sane on USB, rinse, repeat.

http://wiki.osdev.org/Universal_Serial_ ... Capability
by ahull
Sat Nov 25, 2017 2:08 am
Forum: General discussion
Topic: OverClock. at Runtime ~90MHz
Replies: 25
Views: 260

Re: OverClock. at Runtime ~90MHz

I know next to nothing about USB, however a bit of google fu turned up this....

https://www.compuphase.com/electronics/usb_lowspeed.htm
by ahull
Sat Nov 25, 2017 1:33 am
Forum: General discussion
Topic: OverClock. at Runtime ~90MHz
Replies: 25
Views: 260

Re: OverClock. at Runtime ~90MHz

Just a thought, but is USB interrupt driven, if so, then perhaps switching to a suitable cpu clock speed could be handled by the interrupt handler, assuming that doing so only took a few CPU cycles. I presume things are not that simple, since there is a USB peripheral clock involved somewhere in the...
by ahull
Fri Nov 24, 2017 5:14 pm
Forum: Code snipplets
Topic: Dual LFO with choice of waveforms using PT8211 and Blue Pill
Replies: 7
Views: 71

Re: Dual LFO with choice of waveforms using PT8211 and Blue Pill

.. or you could build the pig-o-scope and use that to measure the waveforms :D it has no filtering or buffering whatsoever.
by ahull
Fri Nov 24, 2017 5:03 pm
Forum: Code snipplets
Topic: Dual LFO with choice of waveforms using PT8211 and Blue Pill
Replies: 7
Views: 71

Re: Dual LFO with choice of waveforms using PT8211 and Blue Pill

Those square waves look like they are being passed through some sort of L/C or R/C filter, are you sure the issue is not with your scope or probes. Try the scope on DC coupled rather than AC coupled, since the frequency is so low. If that makes no difference, try a couple of short wires in place of ...
by ahull
Fri Nov 24, 2017 2:36 pm
Forum: Postbag
Topic: Rogers postbag
Replies: 94
Views: 5581

Re: Rogers postbag

ag123 wrote:
Fri Nov 24, 2017 1:25 pm
Google ads:
This is off topic, but I'm thinking given the traffic you may like to host google ads, they could in some ways help to lower the cost of running this, just 2c
You wont get much revenue from me I'm afraid, my adblocker will bin the ads. :lol:
by ahull
Thu Nov 23, 2017 1:06 am
Forum: Projects
Topic: Complete dashboard for an old car
Replies: 12
Views: 230

Re: Complete dashboard for an old car

Here is a similar (arguably better) idea using two mosfets. http://www.mosaic-industries.com/embedded-systems/microcontroller-projects/electronic-circuits/push-button-switch-turn-on/microcontroller-latching-on-off The description of how it works should give you a few ideas. My idea is a little simpl...
by ahull
Wed Nov 22, 2017 9:01 pm
Forum: Projects
Topic: Complete dashboard for an old car
Replies: 12
Views: 230

Re: Complete dashboard for an old car

You could use a relay and a couple of optoisolators in parallel. The ignition switches on one optoisolator, this provides power to the relay coil, the relay then provides power to the 5V PSU/regulator for the STM, which in turn on power up, switches on optoisolator 2 which is parallel with optoisola...
by ahull
Wed Nov 22, 2017 2:43 am
Forum: Projects
Topic: Complete dashboard for an old car
Replies: 12
Views: 230

Re: Complete dashboard for an old car

I suspect you will need a capacitor of a few hundred uF to run the STM for sufficient time after the 12V goes down. You will also need some form of brownout detection on the 12V line (you may get away with polling a simple voltage divider from an analog input) so you know the power has gone. The siz...
by ahull
Fri Nov 17, 2017 2:01 am
Forum: Off topic
Topic: "New" "Multimeter"
Replies: 12
Views: 457

Re: "New" "Multimeter"

Very nice.. Complete with original user manual I see. :D