6 0 ▁ ▁c , ▁s ▁ <0x09> <0x09> S AD ▁ <0x09> Split ▁add ▁ 6 4 ▁ ▁c , ▁s ▁ <0x09> <0x09> ADD ▁ <0x09> Add ▁ 7 0 ▁ ▁c , ▁s ▁ <0x09> <0x09> SS U ▁ <0x09> Split ▁subtract ▁ 7 4 ▁ ▁c , ▁s ▁ <0x09> <0x09> SUB ▁ <0x09> Sub t ract ▁ ▁Special ▁features ▁of ▁the ▁D - 1 7 B ▁computer ▁include ▁flag ▁store , ▁split - word ▁arithmetic , ▁and ▁minim ized ▁access ▁timing . ▁Flag ▁store ▁provides ▁the ▁cap ability ▁of ▁storing ▁the ▁present ▁contents ▁of ▁the ▁accum ulator ▁while ▁executing ▁the ▁next ▁Inst ruction . ▁Split - word ▁arithmetic ▁is ▁used ▁in ▁performing ▁arithmetic ▁operations ▁on ▁both ▁hal ves ▁of ▁a ▁split ▁word ▁at ▁the ▁same ▁time . ▁A ▁split ▁word ▁on ▁the ▁D - 1 7 B ▁consists ▁of ▁ 1 1 ▁bits . ▁Min im ized ▁access ▁timing ▁is ▁the ▁placing ▁of ▁instructions ▁and ▁data ▁in ▁memory ▁so ▁that ▁they ▁are ▁available ▁with ▁minimum ▁delay ▁from ▁the ▁disk ▁memory . ▁ ▁Gu id ance ▁software ▁Aut on et ics ▁was ▁the ▁associate ▁contract or ▁for ▁the ▁Min ut eman ▁( MM ) ▁guidance ▁system , ▁which ▁included ▁the ▁flight ▁and ▁pre launch ▁software . ▁This ▁software ▁was ▁program med ▁in ▁assembly ▁language ▁into ▁a ▁D 1 7 ▁disk ▁computer . ▁TR W ▁provided ▁the ▁guidance ▁equations ▁that ▁Aut on et ics ▁program med ▁and ▁was ▁also ▁responsible ▁for ▁the ▁ver ification ▁of ▁the ▁flight ▁software . ▁When