Invalid CRC or Not enough bits

[xrmb]

First of all the code works pretty well and I can easily work around the issue! But sometimes I get random errors like "Invalid CRC" or "Not enough bits". I get what is going on there in the code, I just dont know if it is an issue with my hardware, some timing issue or a sensor issue.

Is that normal?

Thanks in advance.

$dht22 -p 71 -d 1000

Humidity: 44.1 %
Temperature: 29.2 *C
Humidity: 44.0 %
Temperature: 29.2 *C
Humidity: 44.0 %
Temperature: 29.1 *C
Humidity: 44.0 %
Temperature: 29.1 *C
Invalid CRC
Not enough bits: 0
Not enough bits: 0
Not enough bits: 0
Humidity: 44.0 %
Temperature: 29.1 *C
Humidity: 43.9 %
Temperature: 29.1 *C
Humidity: 44.0 %
Temperature: 29.1 *C
Not enough bits: 39
Not enough bits: 0
Not enough bits: 0
Not enough bits: 0
Humidity: 44.0 %
Temperature: 29.1 *C

[ayufan]

It is run in userspace and sometimes kernel switches context and you then fail to read the data.

…

On Tue, Jul 25, 2017 at 2:28 AM, xrmb ***@***.***> wrote: First of all the code works pretty well and I can easily work around the issue! But sometimes I get random errors like "Invalid CRC" or "Not enough bits". I get what is going on there in the code, I just dont know if it is an issue with my hardware, some timing issue or a sensor issue. Is that normal? Thanks in advance. $dht22 -p 71 -d 1000 Humidity: 44.1 % Temperature: 29.2 *C Humidity: 44.0 % Temperature: 29.2 *C Humidity: 44.0 % Temperature: 29.1 *C Humidity: 44.0 % Temperature: 29.1 *C Invalid CRC Not enough bits: 0 Not enough bits: 0 Not enough bits: 0 Humidity: 44.0 % Temperature: 29.1 *C Humidity: 43.9 % Temperature: 29.1 *C Humidity: 44.0 % Temperature: 29.1 *C Not enough bits: 39 Not enough bits: 0 Not enough bits: 0 Not enough bits: 0 Humidity: 44.0 % Temperature: 29.1 *C — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#2>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ACTpQem1BhL4v4DzU_6o_2OzTqKifSD0ks5sRTavgaJpZM4Oh69d> .

[xrmb]

Would running parts of the code in a "critical section" to avoid context switches solve it? Or would that block to long?