Differences

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--- helvar [2023/05/21 17:38] – emozolyak
+++ helvar [2023/09/22 14:33] (current) – emozolyak
@@ Line 39: / Line 39: @@
 PARTIAL_ETX = '$'
 FULL_ETX    = '#'
 function onScanStart ()
     now = os.time()
@@ Line 47: / Line 47: @@
    addDevice{name = "CMD",     shift = 0, base = 10, xtraFields = {} }
 end
 function readRegister (reg, device, unitId)
     if (not readBuffer) then
         readBuffer = 'no data'
     end
+    return readBuffer
-    return readBuffer -- will be assinged in writeRegister
 end
 function writeRegister (reg, device, unitId, newValue)
-    sendString_(newValue) -- expects string to be written externally
+   sendString_(newValue) -- expects string to be written externally
    local buf = {}
+   local tryCount = 0
    repeat
+       tryCount = tryCount + 1 ; DEBUG('tryCount = ' .. tryCount)
        local currentFrame = readUntil(PARTIAL_ETX, FULL_ETX)
-       local lastChar
        if currentFrame then
            table.insert(buf, currentFrame)
            lastChar = currentFrame[#currentFrame]
        end
+    until (lastChar == FULL_ETX or tryCount > 3)
-   until (not lastChar or (lastChar == FULL_ETX))
-   if (#buf > 0) then
+    if (lastChar == FULL_ETX) then
-        for i, row in ipairs (buf) do
+        readBuffer = buf
-            readBuffer[i] = table.concat(row)
+        return true
-        end
+    end
-        readBuffer = table.concat(readBuffer)
-   end
+    readBuffer = 'read bad data!'
+    return true
-   return true
 end
 -------------------------- Helpers --------------------------
 function sendString_(s) -- new sendString version
     local sendBuf = {}
@@ Line 94: / Line 92: @@
     sendBytes(sendBuf)
 end
 function readUntil(endByte1, endByte2) -- read input buffer untils endByte(s) or timeout
+    DEBUG("Entered readUntil.")
     local ONE_BYTE = 1
-    local buf = {}
+    local buf, rb = {}, nil
     repeat
-        local rb = readBytes(ONE_BYTE)
+        rb = readBytes(ONE_BYTE)
         if rb then
-            rb = rb[ONE_BYTE]
+            rb = rb[ONE_BYTE]          ; DEBUG('read byte: ' .. string.char(rb))
             table.insert(buf, rb)
         end
     until (not rb or (rb == endByte1 or rb == endByte2))
-    return ((#buf >= ONE_BYTE) and buf) or false
+    DEBUG("Exit on rb = " .. tostring(rb) )
+    DEBUG('buf = ' .. table.concat(buf, ' '))
+    if (#buf > 0) and (buf[#buf] == endByte1 or buf[#buf] == endByte2) then
+        DEBUG('Got right frame : ') return buf
+    else
+        DEBUG('Got wrong frame : ') ; return false
+    end
 end
 </code>