Search found 6 matches

by davidnorman
Thu Apr 07, 2011 7:44 pm
Forum: Projects
Topic: Potato Gun Ignition Spark Controller
Replies: 6
Views: 6254

Re: Potato Gun Ignition Spark Controller

Now have a manual trigger for sparks. Not long until an electronic one exists. Think I am going to have to optoisolate the XMOS board, since there is considerable voltage spikes going into the board, and occasionally it causes it to lock up.
by davidnorman
Thu Apr 07, 2011 7:35 pm
Forum: General Questions
Topic: Several questions about XMOS
Replies: 54
Views: 48037

Re: Several questions about XMOS

I have seen this effect too. It took a while to track down what was happening. At first we thought it was clock retiming across the L2 cores, then we thought it was unknown delays in the channels, but in the end it turned out to be thread scheduling.
by davidnorman
Sun Apr 03, 2011 8:32 pm
Forum: Projects
Topic: Potato Gun Ignition Spark Controller
Replies: 6
Views: 6254

Re: Potato Gun Ignition Spark Controller

<t>I've implemented the charging code and checked into github. It takes about 10 seconds to put 250v into the main cap. You can get a pretty mean spark from that. I've played with a trigger circuit but no joy yet. May have inadvertently broken the trigger transformer while removing from the other fl...
by davidnorman
Thu Mar 31, 2011 1:56 pm
Forum: Projects
Topic: Potato Gun Ignition Spark Controller
Replies: 6
Views: 6254

Re: Potato Gun Ignition Spark Controller

<t>Assembled the capacitor charging prototype circuit. Picture uploaded. Will tune the charging to make sure that it doesn't overcharge. The current transformer was scavenged from a disposable camera, which works at 1.5V, so the 5V USB power source will overcharge the capacitor. I am hoping that I c...
by davidnorman
Thu Mar 24, 2011 9:53 am
Forum: Projects
Topic: Potato Gun Ignition Spark Controller
Replies: 6
Views: 6254

Re: Potato Gun Ignition Spark Controller

<t>Since the shift registers for the LEDs are 5V, and they don't accept 3.3 as a logic input level, I used the pull-up version of the output port driver, and some external pull-up restistors. Thanks Corin for pointing out that the ports have this feature, and thanks trusty 'Programming XC on XMOS De...
by davidnorman
Sun Mar 20, 2011 12:44 pm
Forum: Projects
Topic: Potato Gun Ignition Spark Controller
Replies: 6
Views: 6254

Potato Gun Ignition Spark Controller

<r>Version: 0.1<br/> Status: Just an idea<br/> License: BSD<br/> Download: <URL url="https://github.com/DavidNorman/XC-1-Potato-Cannon">https://github.com/DavidNorman/XC-1-Potato-Cannon</URL><br/> <br/> The digital supervisor for a high current spark generator used for ignition fuel in the combustio...