Compared to an internal card solution, like Martin I/O card, it offers portability and it is not capable of DMX Full-Duplex operation.
DMXADP is ready to operate and is simply connected to the PC (notebook or desktop) without the requirement to open the case. Multiple DMXADP's may be installed if the PC has multiple LPT ports, up to a maximum of three. For laptops, additional LPT ports may be added with PCMCIA Parallel Port cards (referral information for PC-Card manufacturers available by Digimedia, see More Information section).
The interconnection is shown here (for a Main System Console application):

The most common applications of DMXADP are listed in the following. Refer to Martin ProSceniumDMX Application Page for more details.