The A20 handler is IBM PCmemory manager software[?] providing HMA[?]. XMMs[?] usually provide this functionality. Named after the 21st address line (A20), controlling the access to HMA.
... density is 225.9/km² (584.8/mi²). There are 3,878 housing units at an average density of 177.0/km² (458.2/mi²). The racial makeup of the town is 89.82% ...