The basic code here hard to explain -
9000-9010 is the list of actions, which uses A as a variable.
9100-9115 is the objects.
9100 datame,1,1,0,0 - this is object #1 or the player location
first 1 is the room location, second number is 1=untakable 0=takable
third number is the object it is inside or being carried by. if the player is carrying it the value will be 1
if it is 0, it is not carried or in container
last number 0=not a container or surface 1=open container 2=closed 3=surface (can put things 'on' it.)
9200-9219 room titles and linkers for north,south,east,west,up, and down.