A spectrometer application of time resolved method spectroscopy has been used in many times of experiment on physical of atomic, molecule and ionized plasma behavior. This paper is completed to make experimental work easier in reading and processing of datum. Using PC and interfaces can make signal convert to digital signals and it can save for long time in a very popular magnetic media. So, we can recall specific signal datum to re analyze or compare with new datum. Beside that, the spectrum of any saved datum can be printed many times.This half automatic spectrometer consists of:- Delay and Gating time,- Sample and Hold.- Analog to Digital Conversion ( ADC ).This design consists some modules of software that have been written in C language, and have compiled by a Borlan C compiler.