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OA47

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Joined: 11/04/2012
Location: Australia
Posts: 926

Posted: 02:36am 21 Oct 2023

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I am trying to chase a consistent error in one of my projects. Basically an F4 mite is sending out serial data to a radio unit and waits for a reply from the targeted remote radio unit. If a reply is not received after 5 attempts the mmbasic will raise an alarm code and continue operation. The alarm codes are collected by a VBasic program along with other monitoring tasks and logged to the PC HDD.
Here is a selection of error logs over a couple of days.

08/10/2023 13:45:57 081023 130159 Transmission Alarm RTU09

09/10/2023 14:45:51 091023 140159 Transmission Alarm RTU09

09/10/2023 15:45:51 091023 150159 Transmission Alarm RTU09

09/10/2023 17:45:51 091023 170159 Transmission Alarm RTU09

09/10/2023 22:46:00 091023 220210 Transmission Alarm RTU10

10/10/2023 13:45:13 101023 130126 Transmission Alarm RTU10

11/10/2023 15:45:41 111023 150200 Transmission Alarm RTU09

16/10/2023 17:45:16 161023 170200 Transmission Alarm RTU09

17/10/2023 16:45:11 171023 160200 Transmission Alarm RTU09

17/10/2023 17:45:10 171023 170200 Transmission Alarm RTU09

The logs show the PC date & time, the mmbasic date & time and the error created.

I am suspicious of coincidences in that these errors are logged when the PC clock is around 45 minutes past the hour but as the mmbasic clock is not synchronized with the PC clock it does not share that time and it is mmbasic that creates the alarm.

Does anyone have any thoughts why this would be happening?

Geoffg

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Joined: 06/06/2011
Location: Australia
Posts: 3194

Posted: 03:25am 21 Oct 2023

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Typically mysterious problems with the serial interface are the result of not realising that both send and receive are buffered.

Your description does not provide enough information but, for example, when you send the serial data to the remote radio unit it will be be buffered and sent out while your program continues. If your program then immediately looks for a response you will receive nothing because the radio unit will still be receiving the data being sent to it.

Geoff

Geoff Graham - http://geoffg.net

OA47

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Joined: 11/04/2012
Location: Australia
Posts: 926

Posted: 04:42am 21 Oct 2023

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Thanks Geoff, I am fairly certain that the RS232 port is functioning ok. Heres the code that handles the send and receive of the radio message.

Sub SendMsg
For I = 1 To Retry
On Error Skip
Open "COM1:9600" As #1 'Re-Open port to LoRa Radio Unit
Print #1, Msg$ 'Send out to Radio
Do
Loop Until Lof(#1)=1024 'Wait until Tx Buffer is clear
DbMsg$ = "Radio output:" + Msg$+" #"+Str$(I) : DbPrnt

StartTime=Timer
Do

Loop Until Timer > StartTime + TxTime OR Loc(#1) > 12
RCMsg$=""
If Loc(#1) > 12 Then 'At least 12 characters in Rx Buffer
Pause 100 'Allow time for the rest of the message
RCMsg$=Input$(80,#1) 'Have reply
' Strip out the LINE FEED character from reply
If Left$(RCMsg$,1)=Chr$(10) Then RCMsg$=Right$(RCMsg$,Len(RCMsg$)-1)
If Right$(RCMsg$,Len(RCMsg$)-1) = Chr$(10) Then
RCMsg$=Left$(RCMsg$,Len(RCMsg$)-1)
EndIf
If Left$(RCMsg$,3)="RTU" Then 'Check Reply is from targeted RTU
'Check for Pressure reply
If Mid$(RCMsg$,4,2)= Mid$(Msg$,2,2) Then RCMsg$=Left$(RCMsg$,12)
'Check for probe reply
If Mid$(RCMsg$,6,2)= Mid$(Msg$,2,2) Then RCMsg$=RCMsg$
Else
RCMsg$="?"+ RCMsg$
EndIf
DbMsg$= "Reply:" + RCMsg$ :DbPrnt
Close #1
LkForMsg
On Error Skip
Open "COM1:9600" As #1 'Re-Open port to LoRa Radio Unit
Exit For
Else
DbMsg$= Str$(TxTime/1000) + " Sec Timeout RTU"
If Left$(RCMsg$,3)="RTU" Then
DbMsg$ = DbMSG$ + Mid$(RCMsg$,4,2)
Else
DbMsg$ = DbMsg$ + Mid$(Msg$,2,2)
EndIf
DbMsg$ = DbMsg$ + " #"+Str$(I)
DbPrnt
EndIf

'Set alarm condition for remote
If I = Retry Then
DbMsg$= "Transmission Alarm RTU"+ Mid$(Msg$,2,2):DbPrnt
AlarmOn
EndIf
Next I
EndIf
End Sub

I am thinking that I will have to forensically examine the timing of the SendMsg sub.

Regards
Graeme (OA47)

JohnS
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Joined: 18/11/2011
Location: United Kingdom
Posts: 3802

Posted: 06:35am 21 Oct 2023

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The EndIf just before the End Sub looks odd. Unmatched? Misplaced?

The logic about LF chars is ... unusual.

John

OA47

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Joined: 11/04/2012
Location: Australia
Posts: 926

Posted: 07:02am 21 Oct 2023

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John, I think you are right about that last end if. The logic for the removal of the LF char is to test for a missed one at the start of the message and the definite one at the end of the message. I had to do this to accommodate the Visual Basic software.
Graeme (OA47)

lizby
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Joined: 17/05/2016
Location: United States
Posts: 3150

Posted: 12:41pm 21 Oct 2023

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Well-spotted re ENDIF.

More consistent formatting discipline might help to reveal such inconsistencies as the dangling ENDIF, i.e., indent after SUB, FOR, DO, IF until the closing command is reached (unless the entire command is on a single line).

PicoMite, Armmite F4, SensorKits, MMBasic Hardware, Games, etc. on fruitoftheshed

JohnS
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Joined: 18/11/2011
Location: United Kingdom
Posts: 3802

Posted: 01:31pm 21 Oct 2023

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I didn't count, just happened to see it - if it's dangling does the program work if it's fixed?

John

OA47

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Joined: 11/04/2012
Location: Australia
Posts: 926

Posted: 01:22am 22 Oct 2023

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I just checked the running software and that EndIf is not in the sub. I must have somehow added it when I cut and pasted into the post. I will synchronize the clocks and see if any other pattern occurs in the error codes.

OA47

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