Direct memory access (DMA) computer interface for an optical multichannel analyzer

Abstract

A computer interface for a PARC model 1205A Optical Multichannel Analyzer (OMA) is described. This interface uses the output from the OMA’s internal analog-to-digital converter rather than the usual parallel I/O facility. The ADC output is transmitted from the OMA to the computer over a single 75-Ω coax cable. Since the data obtained from each OMA scan may be stored in the computer memory, extremely versatile processing algorithms may be used, and normal OMA operation is not affected. The software used is also described.