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palcal

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Joined: 12/10/2011
Location: Australia
Posts: 1993

Posted: 12:31am 07 Apr 2019

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@ TassyJim

Do
If Loc(#1)<>0 Then
D$=Input$(1,#1)
Weather$=Weather$+D$ ' Weather$ contains all the data
EndIf
Loop Until D$=Chr$(13)
D$="" 'clear end of line flag
Close #1
Print "Weather$ ";Weather$
Print Len(Weather$)
If Asc(Weather$)<32 Then Weather$=Mid$(Weather$,2,13)
OutTemp$=Left$(Weather$,2)+"`" 'split up Weather$ to regain data
OutHum$=Mid$(Weather$,3,2)+"%"
Rain$=Mid$(Weather$,5,3)
RY$=Mid$(Weather$,8,3)
RYear$=Right$(Weather$,3)
Rainfall$=Rain$+" "+RY$+" "+RYear$
Weather$="" 'clear Weather$

This is the code, I don't see what else I can do to clear the buffer.Edited by palcal 2019-04-08

"It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all"

TassyJim

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Joined: 07/08/2011
Location: Australia
Posts: 6283

Posted: 01:35am 07 Apr 2019

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This should clear any left over characters in the system.

pause 20
junk$=Input$(Loc(#1),#1)

An alternative way to capture the data:

If Loc(#1)<>0 Then
pause 100 ' wait long enough for all text to arrive. Time depends on baud rate
Weather$==Input$(Loc(#1,#1) ' grab everything
' Weather$ contains all the data
EndIf
...

RYear$=Mid$(Weather$,11,3)

In both cases, the PAUSE time depends on the number of characters and the baud rate.
The values given are probably way too high (but longer than needed works OK)

Jim

VK7JH
MMedit

palcal

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Joined: 12/10/2011
Location: Australia
Posts: 1993

Posted: 02:59am 07 Apr 2019

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@ TassyJim.

Thanks I think that has fixed it.Edited by palcal 2019-04-08

"It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all"

Turbo46

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Joined: 24/12/2017
Location: Australia
Posts: 1642

Posted: 06:31am 07 Apr 2019

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Palcal,

I don't know if this helps but it works for me:

Quote '
OPEN "Com1:9600,,RxMsg,5" AS #1
'
' Receive the master's message
SUB RxMsg
RXD$ =""
Cnt = 0
DO
IF LOC(#1)<>0 THEN
RXD$ = RXD$ + INPUT$(1,#1)
Cnt = 0
ELSE
PAUSE 5 ' Wait longer than 1 character
Cnt = Cnt + 1
ENDIF
LOOP UNTIL Cnt = 2
END SUB
'
' Send the Response message
SUB TxMsg
PRINT #1, TXD$;
END SUB
'

It's part of a Modbus slave. The messages are variable in length and can end in any character (ie. a CRC). The end of the message is detected by waiting for a period of more that two character lengths with no character being received.

The message is received in an interrupt routine - it's a bit long but the slave has nothing else to do until the master tells it what to do anyway.

Bill

Keep safe. Live long and prosper.

palcal

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Joined: 12/10/2011
Location: Australia
Posts: 1993

Posted: 07:05am 07 Apr 2019

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Thanks for that Bill but my code is working OK now, I have saved your code and will keep it in mind.

"It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all"

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