diff --git a/libsrc/geos/disk/Makefile b/libsrc/geos/disk/Makefile
index da38f9a30..519dc0bfb 100644
--- a/libsrc/geos/disk/Makefile
+++ b/libsrc/geos/disk/Makefile
@@ -12,7 +12,8 @@ S_OBJS	= blkalloc.o calcblksfree.o changediskdevice.o chkdkgeos.o enterturbo.o e
 	  nxtblkalloc.o opendisk.o purgeturbo.o putblock.o putdirhead.o readblock.o\
 	  readbuff.o setnextfree.o setgeosdisk.o writeblock.o writebuff.o verwriteblock.o\
 	  gettrse.o\
-	  dio_openclose.o dio_cts.o dio_stc.o dio_read.o dio_write.o dio_writev.o
+	  dio_openclose.o dio_cts.o dio_stc.o dio_read.o dio_write.o dio_writev.o\
+	  dio_params.o
 
 all: $(S_OBJS)
 
diff --git a/libsrc/geos/disk/dio_params.s b/libsrc/geos/disk/dio_params.s
index 77ba92732..8d3d0b3ab 100644
--- a/libsrc/geos/disk/dio_params.s
+++ b/libsrc/geos/disk/dio_params.s
@@ -3,11 +3,14 @@
 ; 2.7.2001
 ;
 ; this function is used by dio_read and dio_write to fix parameters (secnum)
-;
+; this function calls SetDevice so that more than one drive can be used at once
 
 	.import		popax,pushax,_dio_log_to_phys
+	.importzp	ptr1
  	.export		dio_params,dio_secnum
-	.include "../inc/geossym.inc"
+	.include 	"../inc/geossym.inc"
+	.include	"../inc/jumptab.inc"
+	.include	"../inc/dio.inc"
 
 .bss
 dio_secnum:	.res 2
@@ -21,6 +24,17 @@ dio_secnum:	.res 2
 	jsr popax
 	sta dio_secnum
 	stx dio_secnum
+
+	jsr popax		; get 3rd parameter
+	jsr pushax		; put it back
+	sta ptr1
+	stx ptr1+1
+	ldy #sst_driveno
+	lda (ptr1),y
+	clc
+	adc #8
+	jsr SetDevice		; setup device, load driver
+
 	lda #<dio_secnum
 	ldx #>dio_secnum
 	jsr pushax