Note: While most of these devices can be reached via a range of addresses due to the partial address decoding, code should never use any address other than the canonical one (all 'x'/don't care positions filled by 1's). Otherwise multiple devices will be enabled simultaneously, which is unlikely to be what you want.
{|{{Prettytable|width: 700px; font-size: 2em;}}class="wikitable"|'''!I/O'''||'''!Decoded as'''||'''!Port'''||'''!Read'''||'''!Write'''
|-
|#1C00||%x0xxxx00 xxxxxxxx||[[Dk'tronics Lightpen]] faulty mirror of #BCXX [[CRTC]] Index|| - ||Write