http://forums.leaflabs.com/topic.php?id=812 A place to share, learn, and grow... en-US Fri, 22 Jan 2016 00:24:13 +0000 http://bbpress.org/?v=1.0.2 q http://forums.leaflabs.com/search.php http://forums.leaflabs.com/topic.php?id=812#post-4917 Tue, 31 May 2011 17:38:20 +0000 poslathian 4917@http://forums.leaflabs.com/ <p>Also note that auto-reset programming will be disabled when using SerialUSB.end(), requiring the button-mashing perpetual bootloader mode. SerialUSB can be re-enabled, however, with SerialUSB.begin() </p> http://forums.leaflabs.com/topic.php?id=812#post-4916 Tue, 31 May 2011 16:07:50 +0000 mbolivar 4916@http://forums.leaflabs.com/ <p>Jason,</p> <p>Thanks for the updates. Does disabling USB and SysTick (via SerialUSB.end() and systick_disable() respectively) resolve the issue?</p> <p>Also, be aware that micros() and millis() won't work without SysTick. </p> http://forums.leaflabs.com/topic.php?id=812#post-4878 Mon, 30 May 2011 01:02:00 +0000 vonnieda 4878@http://forums.leaflabs.com/ <p>I believe I have tracked this down to either the systick or the USBSerial. I saw another post talking about both of those issuing a high priority interrupt and that seems to be the problem. </p> http://forums.leaflabs.com/topic.php?id=812#post-4874 Sun, 29 May 2011 14:54:34 +0000 vonnieda 4874@http://forums.leaflabs.com/ <p>Forgot to mention, I am using Maple IDE 0.0.10beta on a Maple rev 5. </p> http://forums.leaflabs.com/topic.php?id=812#post-4873 Sun, 29 May 2011 14:49:27 +0000 vonnieda 4873@http://forums.leaflabs.com/ <p>Hi all, I am working on some timer stuff to eventually implement a multi-axis stepper driver. I'm noticing that during the first few seconds of operation I get some weird timer artifacts. </p> <p>Here is a screenshot showing the behavior: <a href="http://dl.dropbox.com/u/19742583/Screen%20shot%202011-05-29%20at%2012.41.46%20PM.png" rel="nofollow">http://dl.dropbox.com/u/19742583/Screen%20shot%202011-05-29%20at%2012.41.46%20PM.png</a></p> <p>And here is the sketch that is running:</p> <pre><code>HardwareTimer timer1(1); // GPIOA_BASE-&gt;ODR |= BIT(3) void setup() { pinMode(0, OUTPUT); digitalWrite(0, LOW); timer1.pause(); timer1.setPrescaleFactor(72); timer1.setChannel1Mode(TIMER_OUTPUT_COMPARE); timer1.setCompare(TIMER_CH1, 1); timer1.setOverflow(0xffff); timer1.attachCompare1Interrupt(handler1); timer1.refresh(); // adding a delay(2000) here causes the weirdness to never happen timer1.resume(); } void handler1() { if (digitalRead(0) == LOW) { digitalWrite(0, HIGH); timer1.setCompare(TIMER_CH1, timer1.getCompare(TIMER_CH1) + 10); } else { digitalWrite(0, LOW); timer1.setCompare(TIMER_CH1, timer1.getCompare(TIMER_CH1) + 60); } } void loop() { }</code></pre> <p>What I am seeing is that about a .25 seconds after startup I seem to miss the interrupt that turns off the output, so the timer does a full cycle (65ms) and then it happens again about 1 second in. After this it is fine and remains stable. If I add a 2000 ms delay before I resume the timer (starting it) this never happens. </p> <p>My guess is that the Maple library is setting something up during the first second of operation, but I have not confirmed that. </p> <p>Does anyone have any ideas as to what might be going on?</p> <p>Thanks,<br /> Jason von Nieda </p>