I'm looking to log data for four RS-232 serial devices that will burst data (CR/LF terminated ASCII strings) at 1 Hz for 10 seconds every XX minutes, where XX is probably 15. On each serial device, I can specify data rate (1 Hz), burst size (10 samples), and burst interval (15 min = 900 s). The devices are not synchronized.
Inelegant solution: Starting wtih just one sensor, I scan continuously a 1 Hz and test the value NBytesReturned from SerialInRecord. (NBytesReturned is guaranteed to be >= 42 if the sensor has valid output.) So, I conditionally CallTable based on the value of NBytesReturned.
The nice thing about this is that I don't have to change any code should I change the burst interval on any device.
This works reliably, I think I can do the same trick in the Main program with the other devices inside the same Scan loop. But is there a more elegant solution?
-- Eric
DataTable (EcoTriplet,1,-1) 'Set table size to # of records, or -1 to autoallocate.
Sample (1,Chl470,Long)
Sample (1,Beta700,Long)
Sample (1,FDOM,Long)
Sample (1,RawString,String)
EndTable
'Define Subroutines
'Sub
'EnterSub instructions here
'EndSub
'Main Program
BeginProg
SerialOpen (PortEco,19200,0,0,200,0)
Scan (1,Sec,3,0)
'Each Eco record is a tab-delimited string of 42-48 bytes plus :
'99/99/99 99:99:99 695 xx38 700 xx49 460 xx41 999
SerialInRecord (PortEco,RawString,&h0A,0,&h0D,NBytesReturned,01)
'Get counts for each measurement by splitingt string at tabs CHR(09)
SplitStr (SplitStrings(1),RawString,CHR(09),9,5)
Chl470=SplitStrings(4) 'xx38, where xx are additional digits
Beta700=SplitStrings(6) 'xx49
FDOM=SplitStrings(8) 'xx41
'Update table
If NBytesReturned >= 42 Then
CallTable EcoTriplet
EndIf
NextScan
EndProg