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Changes for page 05 Lua Script

Last modified by Devin Chen on 2025/03/04 14:07
From version 21.3
edited by Hunter
on 2022/12/14 11:39
Change comment: There is no comment for this version
To version 25.1
edited by Hunter
on 2023/03/01 12:04
Change comment: There is no comment for this version

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... ... @@ -90,7 +90,7 @@
90 90  
91 91  This example shows how to parse value from subscribing MQTT topic. Get the value and calculate the average value for group F1, F2, F3 and F4. The testing topic name is "testtopic/test/no1/123456".
92 92  
93 -Download link
93 +[[Download link>>https://ftp.we-con.com.cn/Download/WIKI/PI%20HMI/Demo/Lua%20Script/MQTT%20JSON%20parse.zip]]
94 94  
95 95  And the subscribed content is like following:
96 96  
... ... @@ -227,4 +227,16 @@
227 227  (% style="text-align:center" %)
228 228  [[image:MQTTJSONparsefunction.png]]
229 229  
230 += **11 High-Low Byte Switch** =
231 +
232 +Main function is like following:
233 +
234 +{{code language="lua"}}
235 +local lowByte = val & 0x00ff
236 +local shiftHigh = lowByte << 8
237 +local highByte = val & 0xff00
238 +local shiftLow = highByte >> 8
239 +local newVal = shiftHigh|shiftLow
240 +{{/code}}
241 +
230 230