Visual basic application in computer hardware control and data acquisition
Speech Recognition Technology enables text acquisition via users’ dictation and knowledge gain through system dictation. In this paper the application of speech recognition technology in hardware device control and data acquisition is experimented using Visual Basic and the Speech Application Programming Interface (SAPI) Software Development Kit. To control hardware using Visual Basic, all hardware requests were designed to go through Windows via the printer parallel ports which is accessed and controlled by means of the Printer object. A ULN2003A Relay Driver which contains 7 separate Darlington pairs with common emitters and three modified Transistor- Transistor-Logic circuit (i.e. 74LS365) were used to interface an analog-to-digital converter and the parallel port of the computer. The seven light emitting diodes were driven by the ULN2003A with each pair being rated at 500mA, which can also withstand surges up to 600mA. The proposed speech recognition system enabled data read by the control software to be stored in a file for later use. Also the system was able to reads the system input state via words like “one” which kindle output 1, “four” or “for” for output 4, etc of the different input port to the interfacing hardware device.