My setup is weewx 5.1.0 on a 4 GB RPI-4 on bookworm talking to a Davis Envoy with the USB data logger. The Davis hardware is about one year old, current firmware. My station isn't up yet, so the Envoy isn't receiving any data but it is reporting inside temp, humidity, and barometer so I can tell weewx is receiving loop packets. Using John Kline's suggestion, I modified the vantage.py driver as he suggested and that appears to be a useful "light weight" recovery mechanism for the short (always zero bytes) loop packets. About every 15 minutes, I see a block of the "ShortReadIOError" exceptions. Each block of exceptions corresponds to approximately 36 or so loop packets. A few packets with the block are received w/o any retries. Then there will be 15 minutes of error free reception. The RPI journal log doesn't show any RPI OS activity when a block of the ShortReadIOError exceptions starts. The USB cable is fine as DMP and DMPAFT commands work fine w/o errors. It's like my Envoy gets stupid every 15 minutes. This seems quite consistent. Save for the exceptions, everything seems to be working.
This behavior has me suspecting my Envoy more than my RPI. I wonder if the lack of receiving any ISS data causes the Envoy to "do something" about every 15 minutes that interferes with executing LOOP or LPS commands. On Wednesday, May 25, 2022 at 7:45:30 AM UTC-6 WindnFog wrote: > A powered hub makes it just as bad, and possibly worse, Tom. But, with > your "more forgiving" Vantage driver, it is far better than before. So I > am quite willing to live with it as it is. > > As mentioned in the same thread, I removed my cron job that calls a > program, and I'm using the tags you recommended based on the NOAA > generation template. That's a far better approach. > > - Paul VE1DX > On Wednesday, May 18, 2022 at 9:38:17 PM UTC-3 Graham Eddy wrote: > >> i reported earlier that i got a burst of weewx restarts by vantage driver >> when my extra vp2 station (wireless temp) battery started reporting low (i >> hadn’t noticed until this thread started). tom’s new retry patch not >> applied. this happened a second time recently viz. burst of restart >> activity when extra station reported low battery. nothing to do with power >> supplies or reboots, i am more inclined to point to an envoy or data >> logger/usb firmware bug (they are more than 15yo). >> (it is possible this firmware bug could lead to phantom battery low >> reports; i think more likely they were genuine battery low events driving >> the error) >> >> sadly this extra wireless vp2 station has just been borked - it was under >> water for a week in 2010 floods (i mounted it higher after that :-) but a >> few days ago couldn’t survive 2-3 tonnes of tree branch crushing it on >> rocks. it will be replaced by a much much cheaper ecowitt remote temp probe >> (i run dual vp2/gw1000) >> >> On 19 May 2022, at 1:09 am, Paul Dunphy <foc...@gmail.com> wrote: >> >> Whatever it is, it's related to RPis talking to a Davis Logger via >> USB. I have a couple of powered USB hubs lying around. I can try putting >> one of them on in the next day or so . . . now that you mention it, I never >> had any trouble with an RPi 3. However, it did/does manifest itself on >> three different RPi 4s. I'll report back when I have results using a >> powered hub. >> >> - Paul VE1DX >> >> On 2022-05-18 11:14 a.m., Tom Keffer wrote: >> >> I don't know that it's a "timing issue," but it could certainly be a >> power issue. >> >> The USB power supplies for many RPis can be barely adequate. In >> particular, the RPi 4 uses a lot of power. It doesn't take much for the >> power to sag, resulting in errors. >> >> >> >snip< >> >> -- >> You received this message because you are subscribed to the Google Groups >> "weewx-user" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to weewx-user+...@googlegroups.com. >> >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/weewx-user/9d5bf73c-2c97-fd8b-6a14-06dfbeb751d3%40gmail.com >> >> <https://groups.google.com/d/msgid/weewx-user/9d5bf73c-2c97-fd8b-6a14-06dfbeb751d3%40gmail.com?utm_medium=email&utm_source=footer> >> . >> >> >> -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to weewx-user+unsubscr...@googlegroups.com. To view this discussion visit https://groups.google.com/d/msgid/weewx-user/5174299f-2102-4d06-9d9a-de1ce40ff04an%40googlegroups.com.
