A microcomputer-controlled multichannel programmable pattern generator

Abstract

In this paper the design of a single-board, microcomputer-controlled, digital pattern generator is discussed. The generator provides eight synchronous, TTL-compatible, NRZ channels. The controller is a 6s02-based Rockwell AIM 65 microcomputer. The generator master clock frequency is 10 MHz, but a single vector can be delayed from 100 ns to 99 000 s. Programmable delays avoid wasting memory in applications requiring short bursts of data followed by long steady-state conditions. Memory depth per channel is 100. The operational speed of the generator is independent of that of the controller. An interactive menu-driven program supports entry and editing of vectors for the sequence. After the sequence is transferred to the generator board the generator can be started/reset locally or by remote. The generator can be configured in the burst or continuous modes.Some attractive features of the design are simplicity of design, low cost, flexibility for expansion of the number of channels/memory deptp er channel, conversion into an arbitrary waveform generator, ap~h cation as a square-wave function generator from 5 JLHz to 5 MHz with programmable duty cycle, and seven supporting channels for trigger (with delay step of 100 ns or more). The generator has been applied in the characterization of nonvolatile semiconductor memory transistors which is an example of different delays between adjacent vectors by several orders of magnitude.

Microcomputer-based pulse stimulator

“…In principle, there are two kinds of microcomputer-based stimula- tars. One is a pattern generator that uses a digital-to-analog converter to generate the am&g v&age or cm%ent (Cavigtia et al, 1983;Roy et al-, 1987). The purpose of a pattern or waveform generator is usually for the simulation of biomedical signals (Kahn, 1989) or other special applications such as selective block (Jaw et al, 1991).…”