WRITE	 MACRO DCB?,0,RBN?,RBA=?,RBN=&3
	 AIF   /&LABEL$$=/ .GO
&LABEL$$ EQU   *
.GO	 AIF   &1=(.REG1
	 LA    2,&1
	 AGO   .RBA
.REG1	 AIF   &1=(2).RBA
	 LR    2,&1
.RBA	 AIF   &RBA=?.RBN
	 AIF   &RBA=(.REG2
	 AIF   &RBA<A.RBAABS
	 MVC   36(4,2),&RBA
	 AGO   .AREA
.REG2	 ST    &RBA,36(0,2)
	 AGO   .AREA
.RBAABS  MVC   36(4,2),=F'&RBA'
	 AGO   .AREA
.RBN	 AIF   &RBN=(.REG3
	 AIF   &RBN<A.RBNABS
	 L     1,&RBN
	 AGO   .MULT
.REG3	 LR    1,&RBN
	 AGO   .MULT
.RBNABS  L     1,=F'&RBN'
.MULT	 MH    1,18(0,2)
	 ST    1,36(0,2)
.AREA	 AIF   &2=(.REG4
	 LA    1,&2
	 AGO   .SVC
.REG4	 AIF   &2=(1).SVC
	 LR    1,&2
.SVC	 SVC   4