This work reports the design and integration of a custom digital signal processor (DSP) system into a pulsed quantum cascade laser (QCL) based trace gas sensor to improve its portability, robustness and operating performance. Specifically, this work describes the implementation of a custom prototype DSP data acquisition/system controller based on the Texas Instruments TMS320F2812 for embedded control and processing. In addition, the sensor incorporates oversampling by taking advantage of the high speed conversion capabilities of the analog-to-digital converter (ADC) which is embedded in the DSP. A carbon monoxide (CO) sensor employing a thermoelectrically (TE) cooled, pulsed 4.6 µm distributed feedback (DFB) QCL as a mid-infrared radiation source is used to evaluate the performance characteristics of such a DSP controlled spectroscopic gas sensor.