LeafLabs Garden » User Favorites: drinkdhmo

LeafLabs Garden » User Favorites: drinkdhmo 582 A place to share, learn, and grow... en-US Fri, 22 Jan 2016 00:22:57 +0000 http://bbpress.org/?v=1.0.2 <![CDATA[Search]]> q http://forums.leaflabs.com/search.php nickbike on "hardware quadrature decoding issues" http://forums.leaflabs.com/topic.php?id=110#post-10492 Fri, 04 May 2012 21:45:38 +0000 nickbike 10492@http://forums.leaflabs.com/ I know this post is old, but I have the same request as josiah47. Can some please post a little more code? Maybe something that requests the encoder count and prints to the screen once a second. Thanks! josiah47 on "hardware quadrature decoding issues" http://forums.leaflabs.com/topic.php?id=110#post-4910 Tue, 31 May 2011 12:02:10 +0000 josiah47 4910@http://forums.leaflabs.com/ drinkdhmo, can you provide the model of the encoder you are using and maybe even the full code for the quadrature encoding? or at least just the encoding parts. Thanks drinkdhmo on "hardware quadrature decoding issues" http://forums.leaflabs.com/topic.php?id=110#post-668 Tue, 03 Aug 2010 16:53:04 +0000 drinkdhmo 668@http://forums.leaflabs.com/ Thank you bnewbold!!! That link helped me find a post that showed me the proper register settings to get full (4x) quadrature decoding. Here is the code I used to set up the timer: <pre><code>Timer* encoderTimer; encoderTimer = (Timer*)TIMER4_BASE; encoderTimer->CCMR1 = 0xF1F1; encoderTimer->CCMR2 = 0x0000; encoderTimer->CCER = 0x0011; encoderTimer->SMCR = 0x0003; encoderTimer->CR1 = 0x0001; encoderTimer->CR2 = 0x0000; encoderTimer->PSC = 0x0000; encoderTimer->CNT = 0x0000; //reset the counter before we use it</code></pre> The encoder CHa and CHb pins are connected to Maple pins 5 and 9 respectively. Here is where I found the post that steered me in the right direction: <a href="https://my.st.com/public/STe2ecommunities/mcu/Lists/ARM%20CortexM3%20STM32/Flat.aspx?RootFolder=https%3a%2f%2fmy.st.com%2fpublic%2fSTe2ecommunities%2fmcu%2fLists%2fARM%20CortexM3%20STM32%2fEncoder%20interface%205793&FolderCTID=0x01200200770978C69A1141439FE559EB459D758000626BE2B829C32145B9EB5739142DC17E&currentviews=615" rel="nofollow">https://my.st.com/public/STe2ecommunities/mcu/Lists/ARM%20CortexM3%20STM32/Flat.aspx?RootFolder=https%3a%2f%2fmy.st.com%2fpublic%2fSTe2ecommunities%2fmcu%2fLists%2fARM%20CortexM3%20STM32%2fEncoder%20interface%205793&FolderCTID=0x01200200770978C69A1141439FE559EB459D758000626BE2B829C32145B9EB5739142DC17E&currentviews=615</a> bnewbold on "hardware quadrature decoding issues" http://forums.leaflabs.com/topic.php?id=110#post-663 Tue, 03 Aug 2010 00:27:28 +0000 bnewbold 663@http://forums.leaflabs.com/ Hey drinkhmo! Sorry we didn't get back to you faster... I don't have a quad encoder in hand so I can't test your code on the bench. I also don't see an application note which is too bad. It does look like others have gotten quad encoder inputs working on STM32s, so it should be possible (<a href="https://my.st.com/public/STe2ecommunities/mcu/Lists/ARM%20CortexM3%20STM32/Flat.aspx?RootFolder=/public/STe2ecommunities/mcu/Lists/ARM%20CortexM3%20STM32/Extend%20Quadrature%20Encoder%2016-bit%20register&FolderCTID=0x01200200770978C69A1141439FE559EB459D758000626BE2B829C32145B9EB5739142DC17E&currentviews=157" rel="nofollow">https://my.st.com/public/STe2ecommunities/mcu/Lists/ARM%20CortexM3%20STM32/Flat.aspx?RootFolder=/public/STe2ecommunities/mcu/Lists/ARM%20CortexM3%20STM32/Extend%20Quadrature%20Encoder%2016-bit%20register&FolderCTID=0x01200200770978C69A1141439FE559EB459D758000626BE2B829C32145B9EB5739142DC17E&currentviews=157</a> ). If you're still stuck I can poke through your full code and see if you have any typos. drinkdhmo on "hardware quadrature decoding issues" http://forums.leaflabs.com/topic.php?id=110#post-629 Tue, 27 Jul 2010 13:07:25 +0000 drinkdhmo 629@http://forums.leaflabs.com/ I am using the Maple to read a quadrature encoder. I followed the instructions in the STM Reference Manual on pages 360-362 and got things working. I can hook up an encoder to channels 1 and 2 of a timer (timer 4 in my case) and the counter is able to count the pulses from the encoder. This works very well, except that I need 4x decoding, and it appears that I can only get 1x (TIM4_SMCR:SMS=001) and 2x (TIM4_SMCR:SMS=011) decoding, meaning that the counter is only clocking on rising edges. However, the Reference Manual implies that it is possible to clock on rising and falling edges (see Figure 134). Here is my code that I use to set up the timer: <pre><code>Timer* encoderTimer; encoderTimer = (Timer*)TIMER4_BASE; encoderTimer->CCMR1 |= 0x0001; //CC1S=01 encoderTimer->CCMR1 &= ~(0x0002); encoderTimer->CCMR1 |= 0x0100; //CC2S=01 encoderTimer->CCMR1 &= ~(0x0200); encoderTimer->CCER &= ~(0x0002); //CC1P=0 encoderTimer->CCER &= ~(0x0020); //CC2P=0 encoderTimer->SMCR |= 0x0003; //SMS=011 encoderTimer->SMCR &= ~(0x0004); encoderTimer->SMCR &= ~(0x0F00); //no filter encoderTimer->CR1 |= 0x0001; //CEN=1 encoderTimer->CNT = 0x0000; //reset the counter before we use it</code></pre>