procedure AbreGaveta;
var
Gav : TextFile;
begin
try
try
AssignFile(Gav,'USB001');
{$I-}
REWRITE(Gav);
{$I+}
if IOResult = 0 then
begin
WRITE(Gav,Chr(27)+Chr(112)+Chr(0)+Chr(4)+Chr(4));
end;
except
raise Exception.Create(' Error al abrir gaveta ');
end;
finally
CloseFile(Gav);
end;
end;