problem with communication at midnight

[mtajkov]

do my port through which communication with the controller (ADAM 4000). several times per second the controller sends a request (WRITECOMM (nCommIzl, "$ 02" + "6" + chr (13))) I get a response from him

function BytesAtPort( nCommIzl )

local cBufIzl := Replicate(Chr(255),1024)

ReadComm( nCommIzl, @cBufIzl ) // <<<<---- program will lock here

cBufIzl:=StrTran(cBufIzl,Chr(255),'')

if mCont=.t.
LogFile( dF, {"Response controller: " + cBufIzl } )
endif

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log file:


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07/19/12 23:59:58: Response controller:! 001F00
07/19/12 23:59:58: Response controller:! 001F00
07/19/12 23:59:58: Response controller:! 001F00
07/19/12 23:59:58: Response controller:! 001F00
07/19/12 23:59:59: Response controller:! 001F00
07/19/12 23:59:59: Response controller:! 001F00
07/19/12 23:59:59: Response controller:! 001F00
07/19/12 23:59:59: Response controller:! 001F00
07/19/12 23:59:59: Response controller:! 001F00

The problem is that communication stops at 23:59:59. Why?

Note that the controller does not have its clock!