"Jay West" <jwest at classiccmp.org> wrote: Pretty much. A non-DMA parallel port. Most commonly used for digital data acquisition or as a generic interface to any device with a word you want to put to/from the Unibus. With a little bit of logic level inversion can interface to a parallel printer or plotter. Not high bandwidth, that would use a DMA parallel port like a DR11-W. Occasionally used as inter-CPU communication channel. That's a pretty nifty implementation of 4 DL11's onto a single Unibus board. This the one that's a hex-height board but with a cutout so you can use it in a slot with a Unibus cable on the last two places, right? Tim.