SyncWrite performs a synchronous write of the value, quality and timestamp information for all items either in the group or, if it is not nil, in the parameter aItemList.
The result will be True on successful execution, otherwise False. The function runs to completion before returning because the values are written directly to the physical device. So the function should not return until it is verified that the device has actually accepted or rejected the data. Writing to the device is not affected by the Active state of the group or item.