decode battery voltage

[air-quality] / ble-mijia.sh

diff --git a/ble-mijia.sh b/ble-mijia.sh
index 9659e29..908d63f 100755 (executable)
--- a/ble-mijia.sh
+++ b/ble-mijia.sh
@@ -2,8 +2,11 @@
 mac=A4:C1:38:90:DC:63
 test ! -z "$1" && mac=$1
 
+# based on https://ndimension.design.blog/2021/12/16/reading-data-from-xiaomi-mi-temperature-and-humidity-monitor-2-lywsd03mmc/
+# find sensor with: sudo hcitool lescan
+# A4:C1:38:D8:3F:9C LYWSD03MMC
 
 gatttool -b $mac --char-write-req --handle='0x0038' --value="0100" --listen | \
-       awk 'BEGIN { OFS=","; ORS="\n" } /value:/ { print "temperature=" strtonum("0x"$7$6) / 100, "humidity=" strtonum("0x"$8), "a=" strtonum("0x"$9), "b="strtonum("0x"$10) ; fflush() }' | \
+       awk 'BEGIN { OFS=","; ORS="\n" } /value:/ { print "temperature=" strtonum("0x"$7$6) / 100, "humidity=" strtonum("0x"$8), "battery=" strtonum("0x"$10$9) / 1000 ; fflush() }' | \
        xargs -i curl --silent -XPOST 'http://10.60.0.92:8086/write?consistency=any&db=rot13' --data-binary "mijia,dc=trnjanska,mac=$mac {}"