Not sure I am replying properly to preserve the format desired for this page, but your (Dennis B) response definitely deserves a response from me.
On Monday, May 17, 2021 at 12:39:53 PM UTC-5 Dennis Bieber wrote: > On Mon, 17 May 2021 07:50:02 -0700 (PDT), in > gmane.comp.hardware.beagleboard.user Bruce Chidester > <[email protected]> wrote: > >This leaves me with a total memory of 28K. Storing float's I can store > >7,168 values. I would like to capture 20,000 values in about 250ms. > > Capture from what? > > 80 samples/msec... or 80000 per second. If I converted properly, about > 0.0125msec per sample. > > I will be sampling from an ADC up to 1MHz maybe. > > > >The Derek Malloy tutorial on PRU's ( > >http://exploringbeaglebone.com/chapter15/) claims, "a pool of 2,000,000 > >bytes is allocated for the sample data". Things appear to have changed > >since the writing of that tutorial. No more dynamic Device Tree through > UIO > > The tutorial you reference is based upon the FIRST EDITION of the book > "Additional Content for First Edition" (when it was chapter 13). > > Does the second addition contain the updates to the remote proc process? >and PRU's accessed through Remote Proc. Not sure if the architecture > > Device trees are now loaded by u-Boot. If you really want UIO, there is > a device tree for that... By default, current images use the TI > recommended > RPROC/msg system (partly because that is supposed to work with multiple > types of special processor cores -- the BB AI not only has PRU, but DSP > processors). > > Thanks for the DSP lead...that is awesome as well. > Extract from /boot/uEnv.txt: > > ###PRUSS OPTIONS > ###pru_rproc (4.14.x-ti kernel) > #uboot_overlay_pru=/lib/firmware/AM335X-PRU-RPROC-4-14-TI-00A0.dtbo > ###pru_rproc (4.19.x-ti kernel) > uboot_overlay_pru=/lib/firmware/AM335X-PRU-RPROC-4-19-TI-00A0.dtbo > ###pru_uio (4.14.x-ti, 4.19.x-ti & mainline/bone kernel) > #uboot_overlay_pru=/lib/firmware/AM335X-PRU-UIO-00A0.dtbo > ### > > You would have to uncomment the UIO line, and comment out the active > RPROC line (only one mode allowed at a time); then reboot. > > This is awesome and definitely gives me something to work with > >changed as well. This makes most of the printed material out of date > >concerning PRU's and it's painful to figure out what is current and not. > I > >would love to have these 2,000,000 bytes available in the new > architecture. > > Note that those bytes are allocated in the DDR RAM. There is no > hardware change. > > Glad to know the HW did not change. > > >Needing help with the addressing, and some code samples would be > excellent. > >Hoping someone out there can help me get it. > > > > Might https://github.com/pgmmpk/bbb_pru_adc be of use? Note that the > maximum speed for that code is 15KHz, or just 1/5th of your 80KHz desire. > > > > I'll take a look > -- > 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/b1cdec6f-2b99-4d31-9eea-d537339c6cecn%40googlegroups.com.
