AGET81
         PLA
         STA   RETADR
         PLA
         STA   RETADR+1
         PLA
         STA   :IDX
         PLA
         STA   ADDR1
         PLA
         STA   ADDR1+1
         LDA   #0
         STA   :IDX+1
         LDY   #1
         LDA   (ADDR1),Y
         STA   :ESIZE
         STA   RETLEN
         LDY   #0
         LDA   #0
         TAY
         STY   SCRATCH
         BEQ   :ENTLP
:DOADD
         CLC
         ADC   :IDX
         TAX
         TYA
         ADC   SCRATCH
         TAY
         TXA
:LP
         ASL   :IDX
         ROL   SCRATCH
:ENTLP
         LSR   :ESIZE
         BCS   :DOADD
         BNE   :LP
         STX   :IDX
         STY   :IDX+1
         CLC
         LDA   #2
         ADC   :IDX
         STA   :RES
         LDA   #0
         ADC   :IDX+1
         STA   :RES+1
         CLC
         LDA   :RES
         ADC   ADDR1
         STA   :RES
         LDA   :RES+1
         ADC   ADDR1+1
         STA   :RES+1
         LDY   #0
         LDA   :RES
         STA   ADDR1
         LDA   :RES+1
         STA   ADDR1+1
:LDLOOP
         LDA   (ADDR1),Y
         STA   RETURN,Y
         INY
         CPY   RETLEN
         BCC   :LDLOOP
         BEQ   :LDLOOP
         LDA   RETADR+1
         PHA
         LDA   RETADR
         PHA
         LDY   :RES
         LDX   :RES+1
         LDA   RETLEN
         RTS
:RES     DS    2
:IDX     DS    2
:ESIZE   DS    1