行数制限で見にくいですが、こんなのは?
@BGSYM:DATA "ABCDEF"
@BGNO:DATA 183,184,185,215,216,217
@MAP:DATA "ABC CBA","DEF FDA"
RESTORE @BGICN:READ BGSYM$
DIM BGNO[LEN(BGSYM$)]:COPY BGNO,@BGNO
RESTORE @MAP
FOR Y=0 TO 1
READ A$
FOR X=0 TO LEN(A$)-1
N=INSTR(BGSYM$,A$[X])
IF N>=0 THEN BGPUT 0,X,Y,BGNO[N] ELSE BGPUT 0,X,Y,0
NEXT
NEXT