-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 6/7/2013 1:31 PM, David Bagby wrote: > Hi, > > We (Steve Stallings and I) would like to let you know about a > gadget we’re expecting to bring to Wichita: The K9 SmorgasBoard.
Looks like a great board, and something folks here have been asking for. Just a few comments: In writing and testing my PRU code, the difference between using any random GPIO pin for a task and using a direct PRU output pin is not really that great. Yes, writing to the GPIO ports is a bit slower than the direct output, with greater latency from the write to the output showing up and more jitter, but when outputs are being updated by a PRU task that is cycling every 1-10 uS, having about 100 nS additional latency and a few 10s of nS of extra jitter isn't so bad. For software step-gen, I don't think it matters which I/O pins you pick. My existing code is totally flexible on I/O pin assignment, you can pick any GPIO from any of the 4 banks, and any native PRU output pin, all by changing a hal parameter for that pin. So you can use anything I've written to date with your board as long as you craft an appropriate device tree overlay to get the pin muxing setup. I don't have anything (yet) that talks to any SoC hardware besides the PRU and GPIO (ie: ADC, I2C, PWM, SPI, etc), and I don't even think TI has drivers for the encoders (at least I didn't see them in the device-tree overlay for the counters, where I would have expected them to show up). Some of this is easily handled by user-mode code (ie: ADC, I2C), but HAL drivers for PWM and the encoders is currently left as an exercise for the reader. If I get my 3D stuff going, however, you could probably talk me into helping! :) If you have any specific pinouts setup already, I can help with crafting a hal_pru_generic configuration that will match up with your board. The HAL configuration is _hopefully_ easy to understand, but there's currently no documentation beyond the source code (it's on the list, and will get done prior to the next SD card image release). Keep us posted! - -- Charles Steinkuehler [email protected] -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (MingW32) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iEYEARECAAYFAlGyL64ACgkQLywbqEHdNFyrqACgrcUPVciBKIBZp0D9zwT+nHQm bkUAoKoeWKrDJxP3qslXyo008okkYtlE =yveN -----END PGP SIGNATURE----- ------------------------------------------------------------------------------ How ServiceNow helps IT people transform IT departments: 1. A cloud service to automate IT design, transition and operations 2. Dashboards that offer high-level views of enterprise services 3. A single system of record for all IT processes http://p.sf.net/sfu/servicenow-d2d-j _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
