I found a breakdown of the $ULTW string format. It's built up in four byte HEX strings:
Header = $ULTW (this identifies the report as a Ultimeter Weather Station) *All values are reported in hex format* Field #1, 0000 = Wind Speed Peak over last 5 min. ( reported as 0.1 kph increments) Field #2, 0000 = Wind Direction of Wind Speed Peak (0-255) Field #3, 01FF = Current Outdoor Temp (reported as 0.1 deg F increments) i.e. 01FF = 511 decimal * 0.1 = 51.1 deg F Field #4, 0004 = Rain Long Term Total (reported in 0.01 in. increments) 0.04 inches in this example Field #5, 27C7 = Current Barometer (reported in 0.1 mbar increments) 27C7 = 10183 decimal = 1018.3 Field #6, 0002 = Barometer Delta Value(reported in 0.1 mbar increments) Field #7, CCD3 = Barometer Corr. Factor(LSW) Field #8, 0001 = Barometer Corr. Factor(MSW) Field #9, 026E = Current Outdoor Humidity (reported in 0.1% increments) You know the drill now... Field #10, 003A = 10. Date (day of year since January 1) 58 decimal in this case... it was February 28th, 30 + 28 for Jan and Feb. Field #11, 050F = Time (minute of day) 1295 in this case after conversion to decimal. Field #12, 0004 = Today's Rain Total (reported as 0.01 inch increments)* 0.04 inches in this example Field #13, 0000 = 1 Minute Wind Speed Average (reported in 0.1kph increments)* Example: $ULTW0000000001FF000427C70002CCD30001026E003A050F00040000 Jason K4APR On Wednesday, August 31, 2022 at 8:17:37 AM UTC-4 [email protected] wrote: > > Your comment is hugely helpful; it points out that formatting is already > > done. But that's fully-baked APRS format, not format to be read by a > > device that translates Ultimeter to APRS. Maybe that would help the OP > > though as it may be possible to send AX.25 frames instead? > > Are you saying that WeeWX is already creating AX.25 frames with the $UTLW > format? If so and it's KISS, then that's exactly what I need to feed to a > TNC for the station. In a perfect world, that's exactly what I would > need. WeeWX brings in the data from the AcuRite, formats it to $UTLW, > builds the KISS AX.25 frame and spits it out either via USB (/ttyAMA0 or > whatever) or through the UART pins to a serial interface. > > Jason K4APR > > On Wednesday, August 31, 2022 at 7:21:54 AM UTC-4 Greg Troxel wrote: > >> >> Susan Mackay <[email protected]> writes: >> >> > Looking at my weewx.conf file at the 'StdRESTfull' and 'CWOP' sections, >> I >> > have 'enable' set to the, the 'station' is my callsign and the >> 'passcode' >> > is my APRS passcode. >> > IIRC that was all that I needed to do. It is all documented in the >> Weewx >> > user guide. My weather data appears on the 'aprs.fi' site. >> >> There are two parts to APRS: >> >> transmitting messages over Amateur Radio >> >> sending those messages to the "APRS Internet System", abbreviated >> APRS-IS >> >> The second can happen by an "igate" which receives messages by radio and >> forwards them, or by someone sending direct to APRS-IS nodes over the >> Internet. >> >> I think the OP wants to send messages by radio. >> >> Your comment is hugely helpful; it points out that formatting is already >> done. But that's fully-baked APRS format, not format to be read by a >> device that translates Ultimeter to APRS. Maybe that would help the OP >> though as it may be possible to send AX.25 frames instead? >> >> Greg, N1DAM >> > -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/weewx-user/a1c66824-5362-4cbb-9a66-16cf4290ea71n%40googlegroups.com.
