DHT11の安定性

LCDディスプレイ上に表示させているときは気にならなかったが、一晩データ収集してみると失敗している結果が１か所あった。


pi@rasp3b:/usr/local/sbin $ sudo sqlite3 /tmp/logging.db
SQLite version 3.8.7.1 2014-10-29 13:59:56
Enter ".help" for usage hints.
sqlite> select * from temperatures;
2017-09-09 00:30|raspi3b|46698|27857|1009870|55397|27700|1011630|28000|64000
2017-09-09 00:40|raspi3b|46698|27898|1009886|55673|27800|1011770|29000|66000
2017-09-09 00:50|raspi3b|47236|27919|1009790|55778|27800|1011690|29000|66000
2017-09-09 01:00|raspi3b|48312|27662|1009804|57366|27300|1011700|28000|67000
2017-09-09 01:10|raspi3b|48312|27924|1009851|57148|27800|1011770|29000|66000
2017-09-09 01:20|raspi3b|49388|28058|1009970|57124|28000|1011810|29000|65000
2017-09-09 01:30|raspi3b|49925|28161|1010194|58101|28100|1012090|29000|67000
2017-09-09 01:40|raspi3b|49388|28289|1010121|58818|28200|1011980|29000|68000
2017-09-09 01:50|raspi3b|47774|28274|1010148|58566|28200|1012090|29000|68000
2017-09-09 02:00|raspi3b|47236|28305|1010330|58538|28200|1012280|29000|68000
2017-09-09 02:10|raspi3b|47236|28279|1010521|58392|28100|1012400|29000|68000
2017-09-09 02:20|raspi3b|47236|28294|1010495|58695|28100|1012360|29000|68000
2017-09-09 02:30|raspi3b|47236|28300|1010321|58351|28200|1012200|29000|67000
2017-09-09 02:40|raspi3b|49388|28264|1010444|58251|28200|1012290|29000|67000
2017-09-09 02:50|raspi3b|49388|28238|1010505|58092|28200|1012430|29000|67000
2017-09-09 03:00|raspi3b|47774|27991|1010692|57780|27800|1012530|29000|68000
2017-09-09 03:10|raspi3b|47236|27960|1010823|57890|27800|1012710|29000|68000
2017-09-09 03:20|raspi3b|46160|27929|1010824|57987|27800|1012730|29000|68000
2017-09-09 03:30|raspi3b|46160|27898|1010877|57946|27700|1012780|29000|68000
2017-09-09 03:40|raspi3b|47236|27883|1011085|57992|27800|1012930|29000|67000
2017-09-09 03:50|raspi3b|48312|27837|1011034|57460|27700|1012940|29000|66000
2017-09-09 04:00|raspi3b|49388|27528|1011118|58479|27500|1012910|28000|67000
2017-09-09 04:10|raspi3b|49388|27667|1011115|58222|27600|1012930|29000|67000
2017-09-09 04:20|raspi3b|49388|27698|1011193|58381|27700|1013020|29000|67000
2017-09-09 04:30|raspi3b|49388|27718|1011358|58649|27700|1013160|29000|67000
2017-09-09 04:40|raspi3b|49388|27728|1011349|58761|27700|1013140|29000|67000
2017-09-09 04:50|raspi3b|49388|27703|1011592|58328|27700|1013370|29000|67000
2017-09-09 05:00|raspi3b|49388|27590|1011638|57911|27700|1013450|29000|66000
2017-09-09 05:10|raspi3b|49388|27548|1011777|57816|27700|1013640|29000|66000
2017-09-09 05:20|raspi3b|49388|27481|1011770|57633|27600|1013640|29000|66000
2017-09-09 05:30|raspi3b|49388|27425|1011831|57642|27600|1013700|29000|66000
2017-09-09 05:40|raspi3b|49388|27394|1011962|57484|27500|1013860|29000|65000
2017-09-09 05:50|raspi3b|49388|27363|1012041|57250|27500|1013830|29000|65000
2017-09-09 06:00|raspi3b|49388|27301|1012172|57096|27400|1013960|29000|65000
2017-09-09 06:10|raspi3b|49388|27229|1012207|56780|27400|1014060|28000|64000
2017-09-09 06:20|raspi3b|49388|27229|1012311|56494|27300|1014150|28000|64000
2017-09-09 06:30|raspi3b|49388|27209|1012459|56331|27300|1014220|28000|64000
2017-09-09 06:40|raspi3b|49388|27193|1012486|56115|27300|1014330|28000|63000
2017-09-09 06:50|raspi3b|49388|27193|1012616|56348|27300|1014380|28000|64000
2017-09-09 07:00|raspi3b|49388|27219|1012503|56314|27300|1014350|28000|64000
2017-09-09 07:10|raspi3b|49388|27209|1012615|56278|27300|1014430|28000|64000
2017-09-09 07:20|raspi3b|49388|27214|1012650|56354|27300|1014530|28000|64000
2017-09-09 07:30|raspi3b|49388|27214|1012520|56366|27300|1014380|28000|63000
2017-09-09 07:40|raspi3b|49388|27183|1012572|56289|27300|1014460|28000|64000
2017-09-09 07:50|raspi3b|49388|27199|1012702|56429|27300|1014620|28000|64000
2017-09-09 08:00|raspi3b|49388|27240|1012771|56454|27300|1014650|28000|64000
2017-09-09 08:10|raspi3b|49388|27296|1012814|56252|27400|1014640|29000|64000
2017-09-09 08:20|raspi3b|49388|27281|1012866|55216|27400|1014780|29000|63000
2017-09-09 08:30|raspi3b|49388|27271|1013135|54348|27400|1014910|28000|62000
2017-09-09 08:40|raspi3b|49925|27307|1013039|54018|27400|1014910|29000|62000
2017-09-09 08:50|raspi3b|49388|27363|1013264|54200|27400|1014990|29000|62000
2017-09-09 09:00|raspi3b|49388|27430|1013168|53905|27500|1015050|29000|62000
2017-09-09 09:10|raspi3b|49388|27481|1013228|53376|27500|1015080|29000|61000
2017-09-09 09:20|raspi3b|49925|27518|1013236|53436|27600|1015080|29000|61000
2017-09-09 09:30|raspi3b|49388|27569|1013218|53128|27700|1015020|29000|61000
2017-09-09 09:40|raspi3b|49388|27605|1013070|53089|27700|1014910|0|0
2017-09-09 09:50|raspi3b|49925|27682|1013095|53155|27800|1014930|29000|61000
2017-09-09 10:00|raspi3b|49925|27713|1013095|52678|27800|1014930|29000|60000
2017-09-09 10:10|raspi3b|49925|27790|1013120|52365|27900|1014960|29000|60000
2017-09-09 10:20|raspi3b|50464|27852|1013145|52035|27900|1014950|29000|60000
2017-09-09 10:30|raspi3b|49925|27950|1012995|51285|28000|1014920|29000|59000
2017-09-09 10:40|raspi3b|49925|28022|1012986|50663|28100|1014880|29000|57000
2017-09-09 10:50|raspi3b|49925|28089|1012889|51306|28200|1014830|29000|58000
sqlite>

これでもスクリプト的には5回リトライさせているのに失敗した模様。
まぁDHT11は比較サンプル的な意味で動かしているだけなので落ち着いたら外しちゃうからいいか…