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--- en:pfw:dht22 [2025-04-26 10:07] – [Numerical representation of the measured values] mka
+++ en:pfw:dht22 [2025-04-26 16:16] (current) – [Numerical representation of the measured values] mka
@@ Line 91: / Line 91: @@
 === Temperature ===
-Die nächsten 16-Bit sind die Temperatur in zehntel Grad Celsius.
+The next 16 bits are the temperature in tenths of a degree Celsius. Temperatures from zero degrees and higher can be processed directly using the 16-bit noForth; they correspond to a positive integer.
-Temperaturen ab null Grad und höher können mit dem 16-Bit noForth unmittelbar verarbeitet werden, sie entsprechen einer positiven ganzen Zahl.
-Das Vorzeichen wird vorangestellt. Die ganzen Grad werden links vom Dezcimalpunkt, die Zehntel rechts davon abgebildet. Die Einheit °C wird angegeben.
+Temperatures below zero degrees are represented by the DHT22 as follows: The MSB of the 16-bits is set, but otherwise the temperature is specified as a positive integer. This number format //does not correspond// to the two's complement of noForth. Here, the MSB must first be evaluated to determine the sign. The sign is prepended for output. The measured value can then be further processed as a positive integer.  Whole degrees are displayed to the left of the decimal point, tenths to the right. The unit °C is specified.
 <code>
 : .tmp ( tmp -- )
@@ Line 109: / Line 106: @@
   ;
  </code>
+  * This is already included in the following source code.\\
+  * And here you can see how this was discovered: [[en:pfw:dht22tmpformat|The temperature format of the DHT22]]
@@ Line 115: / Line 115: @@
 [[en:pfw:dht22-msp430g2553-noforth|DHT22 with Launchpad MSP430G2553 and noForth]]
-This program was used to test DHT22 modules before installation. The DHT22 modules were tested for functionality at room temperature, pre-sorted in this way, and then frozen in a bag of moist sand in the freezer and tested again. One module displayed incorrect temperature values in frost conditions. The display of negative values did not comply with the specifications.
+This program was used to test DHT22 modules before installation. The DHT22 modules were tested for functionality at room temperature, pre-sorted in this way, and then frozen in a bag of moist sand in the freezer and tested again. One module displayed incorrect temperature values in frost conditions, the display of negative values did not comply with the specifications.
 ==== More information on the MSP430G2553 ====
@@ Line 136: / Line 136: @@
 To work with the embedded noForth system I use //e4thcom// by Manfred Mahlow.
 https://wiki.forth-ev.de/doku.php/projects:e4thcom
+Sometimes I also use Windows and Teraterm, for example, to log longer MCU outputs to a file. I also prefer it for testing parts of the source code using copy and paste.
 === Logic Analyser ===