The popularity that certain applications such as mobile telephony or mp3 audio reproduction have gained lately, has made it possible the increase in the number and complexity of embedded systems. Depending on the tradeoffs performance/flexibility/cost, several architectures that range from ASIPs to fullcustom computing machines, based on reconfigurable logic, are being used. Here, what we propose, is a new architecture based on a standard microprocessor whose functionally will be enhanced by a reconfigurable datapath, acting as a customized coprocessor. This architecture not only offers a reasonable tradeoff between cost and performance, but also can be easily exploited through the use of a HW/SW compiler.