On Tue, 30 Mar 2021 23:29:16 -0700 (PDT), in gmane.comp.hardware.beagleboard.user set_ <functt-re5jqeeqqe8avxtiumw...@public.gmane.org> wrote:
>Hello, > >Adafruit_BBIO has some type of example plus the library has its >source: >https://github.com/adafruit/adafruit-beaglebone-io-python/tree/master/Adafruit_BBIO#usage > The eQEP is a different creature from eCAP. eQEP is to read quadrature encoded inputs (rotary knobs producing two step waveforms in which the changes between the two identifies which direction the knob is rotating, and how far it has been turned). From the BBB TRM (SPRUH73P) """ 15.4.1 Introduction A single track of slots patterns the periphery of an incremental encoder disk, as shown in Figure 15-130. These slots create an alternating pattern of dark and light lines. The disk count is defined as the number of dark/light line pairs that occur per revolution (lines per revolution). As a rule, a second track is added to generate a signal that occurs once per revolution (index signal: QEPI), which can be used to indicate an absolute position. Encoder manufacturers identify the index pulse using different terms such as index, marker, home position, and zero reference. """ eCAP is, as the TRM describes it """ 15.3.1.1 Purpose of the Peripheral Uses for eCAP include: • Sample rate measurements of audio inputs • Speed measurements of rotating machinery (for example, toothed sprockets sensed via Hall sensors) • Elapsed time measurements between position sensor pulses • Period and duty cycle measurements of pulse train signals • Decoding current or voltage amplitude derived from duty cycle encoded current/voltage sensors """ >On Monday, March 29, 2021 at 3:14:59 PM UTC-5 >papelhi...-re5jqeeqqe8avxtiumw...@public.gmane.org wrote: > >> Someone has made this functionality works? Can be via sysfs, via PRU >> program handling the register, via CPU program handling the registers, or >> any other method? >> >> If yes, can give me an example or the environment details? >> So far the best I've located is some 7 years old: https://linux-arm-kernel.infradead.narkive.com/zeEA4MIa/patch-v3-0-6-iio-pulse-capture-support-for-ti-ecap It appears your question was asked some two years ago at: https://github.com/adafruit/adafruit-beaglebone-io-python/issues/306 {which sort of implies the previous effort was never really completed} -- Dennis L Bieber -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/9j696g9rfqqlvs2bq0g7784ea2n3urnlt8%404ax.com.
