pjkim 22 Posted August 23, 2012 Share Posted August 23, 2012 Trying to figure out interrupts from GPIO pins. I think I found an error in one of the figs for the 2802x (tms320f28027.pdf Revised Jul 2012). If I understand the function of XINT#CR and XINT#CTR where # is 1 to 3, the number should match to XINT#. In the figure, they do not. Another question. Am I correct in understanding that only three GPIO pins at a time can cause interrupts? I want to attach 4 quadrature encoders as inputs. Will I have to poll these rather than use interrupts? Quote Link to post Share on other sites
TI_Trey 38 Posted August 24, 2012 Share Posted August 24, 2012 Pjkim, Yes the diagram is incorrect. It should be XINT1CR/XINT1CTR...etc. Yes, you are correct. Only 3 GPIOs at any given time can be used to create an interrupt, but you may select any 3 GPIOs. You may want to look at using the capture module. You could add a little external hardware to figure out the direction and then just use one of the quadrature signals piped into the capture to figure out rotations/velocity etc. There is only one channel though, so you'll probably need to use external interrupts and the capture. Trey Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.