I've added and committed my proposed changes to twi.py but I can't push my changes in order to create a PR -- I get this error: remote: Permission to matthewwall/weewx-twi.git denied to <...>; fatal: unable to access 'https://github.com/matthewwall/weewx-twi.git/': The requested URL returned error: 403. Any pointers?
On Thursday, January 19, 2023 at 12:16:36 PM UTC-7 pannetron wrote: > I've left my local twi.py reporting what the station reports as > "barometer". I'm pretty sure the station actually reports a calculated > "altimeter" from its pressure sensor. To review, I calibrated my console > to display local pressure adjusted to my altitude. If I let the driver > report values as "pressure" weewx reports crazy high calculated values for > barometer and altimeter. When I change the twi.py -- or the simulator -- > to report only "altimeter", I get nothing in the barometer and pressure > archive records. My weewx.conf is configure to expect "altimeter" from > hardware and both barometer and pressure from software. Where should I > look to see why weewx is not calculating barometer and pressure from > altimeter? I'm fluent in python. I'd prefer this approach to configuring > the twi.py driver to insert the stations readings into "pressure" and then > having to put a large negative offset in weewx,conf to "correct" the > pressure value. Does the calculation of barometer and pressure from > altimeter require some time span of altimeter values? > > On Monday, January 9, 2023 at 3:21:50 PM UTC-7 Jeff A. D. wrote: > >> Barometer uses outdoor temperature for correction. Indoor pressure for >> all practical purposes is the same as outdoor pressure which is determined >> by the weather. >> >> But again, if the algorithm is the same as for the original VP, then the >> barometer corrections depending on temperature at high altitude are pretty >> meaningless, at least to me. Maybe you would get better readings using a >> more consistent indoor reading, but that's not the way it's meant to work >> and wouldn't give true barometer readings, for whatever they're worth. >> Altimeter is far more meaningful in my opinion, and seems to be what >> stations around here use. >> >> On Monday, January 9, 2023 at 2:44:36 PM UTC-7 pannetron wrote: >> >>> Good catch. No, the station has no input for altitude. And I was wrong >>> about setting the tags in twi.py to "altitude" -- that caused issues with >>> the Belchertown skin I use and the value reported to PWSWeather. I changed >>> the tags to "barometer" and things work okay now but I'm left unsure what >>> errors that may introduce into calculated station pressure and altitude >>> pressure values. That's something I can live with. Seems only a few folks >>> use a TWI station so maybe this is good enough as long as the hack is made >>> known as a caveat? >>> >>> I suspect the station displays and reports "gauge pressure." I manually >>> adjusted the station's barometer calibration for my altitude so the console >>> display is meaningful for comparisons with other stations around me and >>> agrees with my Kestrel 3000. The values reported to CWOP compare very >>> well with neighboring stations. Some day I may play with setting the tags >>> in twi.py back to "pressure" and, as others suggested, use a calibration >>> calculation in weewx.conf to get back to true "gauge pressure". >>> >>> One of my questions remains unanswered: since the barometric sensor is >>> indoors, should SLP adjustments for temperature use indoor or outdoor >>> temperature? >>> >>> BTW, Tom, thanks so much for your replies and work on weeWX!!! >>> >>> Russ >>> >>> On Mon, Jan 9, 2023 at 12:55 PM Tom Keffer <tke...@gmail.com> wrote: >>> >>>> Sounds good. >>>> >>>> Just a reality check: if your instrument emits altimeter pressure, then >>>> there must be a way of setting altitude in the instrument. Hope that's >>>> true. >>>> >>>> On Mon, Jan 9, 2023 at 7:23 AM pannetron <pann...@gmail.com> wrote: >>>> >>>>> Update on a revised twi.py. Changing the genLoopPacket "tags" from >>>>> "pressure" to "altimeter" from values parsed from the station reports >>>>> did >>>>> the trick. After some previous changes from strings to binary strings, >>>>> there was a bug with how wind_dir values were parsed so I fixed that, >>>>> too. >>>>> After a few more days of testing, I'll submit a PR. >>>>> >>>>> On Sunday, January 8, 2023 at 10:45:43 AM UTC-7 pannetron wrote: >>>>> >>>>>> On Sun, Jan 8, 2023 at 4:51 AM Tom Keffer <tke...@gmail.com> wrote: >>>>>> >>>>>>> It sounds like the TWI instrument is emitting "altimeter" or >>>>>>> "barometer", but the driver is labelling it "pressure" (i.e., gauge >>>>>>> pressure). So, weewx feels the need to "correct" it to SLP, resulting >>>>>>> in >>>>>>> your enormous pressures. >>>>>>> >>>>>>> I would recommend filing an issue at the TWI repository >>>>>>> <https://github.com/matthewwall/weewx-twi>. Expect it to take a >>>>>>> while. Matthew is swamped. >>>>>>> >>>>>>> Or, better yet, do a fork and submit a PR. >>>>>>> >>>>>>> Cloned weewx-twi, working on a revised driver. The current driver >>>>>> is populating loop packets with "pressure" while the station reports >>>>>> "altitude"... >>>>>> >>>>> -- >>>>> 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/98794c13-7fe5-4475-b164-439a4c2e08a4n%40googlegroups.com >>>>> >>>>> <https://groups.google.com/d/msgid/weewx-user/98794c13-7fe5-4475-b164-439a4c2e08a4n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>> . >>>>> >>>> -- >>>> >>> You received this message because you are subscribed to a topic in the >>>> Google Groups "weewx-user" group. >>>> To unsubscribe from this topic, visit >>>> https://groups.google.com/d/topic/weewx-user/pwYg9Ywilfw/unsubscribe. >>>> To unsubscribe from this group and all its topics, send an email to >>>> weewx-user+...@googlegroups.com. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/weewx-user/CAPq0zEDJvgZSYothF5%3D8_6RH63CE0YZuek-GBDdsEL052vuf%3Dg%40mail.gmail.com >>>> >>>> <https://groups.google.com/d/msgid/weewx-user/CAPq0zEDJvgZSYothF5%3D8_6RH63CE0YZuek-GBDdsEL052vuf%3Dg%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>> -- You received this message because you are subscribed to the Google Groups "weewx-user" group. 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