Changes for page RS485-LN – RS485 to LoRaWAN Converter User Manual

Last modified by Karry Zhuang on 2025/03/06 16:34

From version < 35.3 >

edited by Xiaoling
on 2022/06/02 15:44

To version < 35.1 >

edited by Xiaoling
on 2022/06/02 15:36

Change comment: Uploaded new attachment "image-20220602153621-3.png", version {1}

Raw
Rendered

Summary

Page properties (1 modified, 0 added, 0 removed)

Details

Page properties

Content

@@ -314,36 +314,77 @@
  === 3.3.3 Configure read commands for each sampling ===
  (((
--During each sampling, we need confirm what commands we need to send to the RS485 sensors to read data. After the RS485 sensors send back the value, it normally include some bytes and we only need a few from them for a shorten payload.
++RS485-BL is a battery powered device; it will sleep most of time. And wake up on each period and read RS485 / TTL sensor data and uplink.
++)))
++(((
++During each sampling, we need to confirm what commands we need to send to the sensors to read data. After the RS485/TTL sensors send back the value, it normally includes some bytes and we only need a few from them for a shorten payload.
++)))
++
++(((
  To save the LoRaWAN network bandwidth, we might need to read data from different sensors and combine their valid value into a short payload.
++)))
++(((
  This section describes how to achieve above goals.
++)))
--During each sampling, the RS485-LN can support 15 commands to read sensors. And combine the return to one or several uplink payloads.
++(((
++During each sampling, the RS485-BL can support 15 commands to read sensors. And combine the return to one or several uplink payloads.
++)))
++(((
++**Command from RS485-BL to Sensor:**
++)))
--**Each RS485 commands include two parts:**
++(((
++RS485-BL can send out pre-set max 15 strings via **AT+COMMAD1**, **ATCOMMAND2**,…, to **AT+COMMANDF** . All commands are of same grammar.
++)))
--~1. What commands RS485-LN will send to the RS485 sensors. There are total 15 commands from **AT+COMMAD1**, **ATCOMMAND2**,…, to **AT+COMMANDF**. All commands are of same grammar.
++(((
++**Handle return from sensors to RS485-BL**:
++)))
--2. How to get wanted value the from RS485 sensors returns from by 1). There are total 15 AT Commands to handle the return, commands are **AT+DATACUT1**,**AT+DATACUT2**,…, **AT+DATACUTF** corresponding to the commands from 1). All commands are of same grammar.
++(((
++After RS485-BL send out a string to sensor, RS485-BL will wait for the return from RS485 or TTL sensor. And user can specify how to handle the return, by **AT+DATACUT or AT+SEARCH commands**
++)))
--3. Some RS485 device might has longer delay on reply, so user can use AT+CMDDL to set the timeout for getting reply after the RS485 command is sent. For example
++* (((
++**AT+DATACUT**
++)))
--**AT+CMDDL1=1000** to send the open time to 1000ms
++(((
++When the return value from sensor have fix length and we know which position the valid value we should get, we can use AT+DATACUT command.
++)))
++* (((
++**AT+SEARCH**
++)))
++(((
++When the return value from sensor is dynamic length and we are not sure which bytes the valid data is, instead, we know what value the valid value following. We can use AT+SEARCH to search the valid value in the return string.
++)))
++
++(((
++**Define wait timeout:**
++)))
++
++(((
++Some RS485 device might has longer delay on reply, so user can use AT+CMDDL to set the timeout for getting reply after the RS485 command is sent. For example, AT+CMDDL1=1000 to send the open time to 1000ms
++)))
++
++(((
  After we got the valid value from each RS485 commands, we need to combine them together with the command **AT+DATAUP**.
++)))
++**Examples:**
  Below are examples for the how above AT Commands works.
++**AT+COMMANDx : **This command will be sent to RS485/TTL devices during each sampling, Max command length is 14 bytes. The grammar is:
--**AT+COMMANDx : **This command will be sent to RS485 devices during each sampling, Max command length is 14 bytes. The grammar is:
--
--(% border="1" style="background-color:#4bacc6; color:white; width:499px" %)
--|(% style="width:496px" %)(((
++(% border="1" class="table-bordered" %)
++|(((
  **AT+COMMANDx=xx xx xx xx xx xx xx xx xx xx xx xx,m**
  **xx xx xx xx xx xx xx xx xx xx xx xx: The RS485 command to be sent**
@@ -351,42 +351,90 @@
  **m: 0: no CRC, 1: add CRC-16/MODBUS in the end of this command**
  )))
++(((
  For example, if we have a RS485 sensor. The command to get sensor value is: 01 03 0B B8 00 02 46 0A. Where 01 03 0B B8 00 02 is the Modbus command to read the register 0B B8 where stored the sensor value. The 46 0A is the CRC-16/MODBUS which calculate manually.
++)))
--In the RS485-LN, we should use this command AT+COMMAND1=01 03 0B B8 00 02,1 for the same.
++(((
++In the RS485-BL, we should use this command AT+COMMAND1=01 03 0B B8 00 02,1 for the same.
++)))
++(((
++**AT+SEARCHx**: This command defines how to handle the return from AT+COMMANDx.
++)))
++(% border="1" class="table-bordered" %)
++|(((
++**AT+SEARCHx=aa,xx xx xx xx xx**
++
++* **aa: 1: prefix match mode; 2: prefix and suffix match mode**
++* **xx xx xx xx xx: match string. Max 5 bytes for prefix and 5 bytes for suffix**
++
++
++)))
++
++**Examples:**
++
++~1. For a return string from AT+COMMAND1: 16 0c 1e 56 34 2e 30 58 5f 36 41 30 31 00 49
++
++If we set AT+SEARCH1=1,1E 56 34.      (max 5 bytes for prefix)
++
++The valid data will be all bytes after 1E 56 34 , so it is (% style="background-color:yellow" %)** 2e 30 58 5f 36 41 30 31 00 49**
++
++[[image:1653269403619-508.png]]
++
++2. For a return string from AT+COMMAND1:  16 0c 1e 56 34 2e 30 58 5f 36 41 30 31 00 49
++
++If we set AT+SEARCH1=2, 1E 56 34+31 00 49
++
++Device will search the bytes between 1E 56 34 and 31 00 49. So it is (% style="background-color:yellow" %)** 2e 30 58 5f 36 41 30**
++
++[[image:1653269438444-278.png]]
++
  **AT+DATACUTx : **This command defines how to handle the return from AT+COMMANDx, max return length is 45 bytes.
--(% border="1" style="background-color:#4bacc6; color:white; width:725px" %)
--|(% style="width:722px" %)(((
++|(((
  **AT+DATACUTx=a,b,c**
  * **a: length for the return of AT+COMMAND**
  * **b:1: grab valid value by byte, max 6 bytes. 2: grab valid value by bytes section, max 3 sections.**
--* **c: define the position for valid value.  **
++* **c: define the position for valid value.  **
  )))
++Examples:
--**Examples:**
--
  * Grab bytes:
--[[image:image-20220602153621-1.png]]
++[[image:1653269551753-223.png||height="311" width="717"]]
--
  * Grab a section.
--[[image:image-20220602153621-2.png]]
++[[image:1653269568276-930.png||height="325" width="718"]]
--
  * Grab different sections.
--[[image:image-20220602153621-3.png]]
++[[image:1653269593172-426.png||height="303" width="725"]]
--
--)))
++(% style="color:red" %)**Note:**
++AT+SEARCHx and AT+DATACUTx can be used together, if both commands are set, RS485-BL will first process AT+SEARCHx on the return string and get a temporary string, and then process AT+DATACUTx on this temporary string to get the final payload. In this case, AT+DATACUTx need to set to format AT+DATACUTx=0,xx,xx where the return bytes set to 0.
++
++Example:
++
++(% style="color:red" %)AT+COMMAND1=11 01 1E D0,0
++
++(% style="color:red" %)AT+SEARCH1=1,1E 56 34
++
++(% style="color:red" %)AT+DATACUT1=0,2,1~~5
++
++(% style="color:red" %)Return string from AT+COMMAND1: 16 0c 1e 56 34 2e 30 58 5f 36 41 30 31 00 49
++
++(% style="color:red" %)String after SEARCH command: 2e 30 58 5f 36 41 30 31 00 49
++
++(% style="color:red" %)Valid payload after DataCUT command: 2e 30 58 5f 36
++
++[[image:1653269618463-608.png]]
++
  === 3.3.4 Compose the uplink payload ===
  (((

Changes for page RS485-LN – RS485 to LoRaWAN Converter User Manual

Summary

Details

Applications

Navigation