diff --git a/asminc/atari.inc b/asminc/atari.inc
index 29159a177..9de8e3daa 100644
--- a/asminc/atari.inc
+++ b/asminc/atari.inc
@@ -44,9 +44,34 @@ CLOSE   = $0C           ;close
 STATIS  = $0D           ;status
 SPECIL  = $0E           ;special
 
-; Special Entry Command Equates
+; DOS IOCB command codes
 
-; Screen Commands
+RENAME  = $20           ;rename disk file
+DELETE  = $21           ;delete disk file
+LOCKFL  = $23           ;lock file (set to read-only)
+UNLOCK  = $24           ;unlock file
+POINT   = $25           ;point sector
+NOTE    = $26           ;note sector
+GETFL	= $27		;get file length
+CHDIR_MYDOS	= $29	;change directory (MyDOS)
+MKDIR	= $2A		;make directory (MyDOS/SpartaDOS)
+CHDIR_SPDOS	= $2C	;change directory (SpartaDOS)
+FORMAT  = $FE           ;format
+
+GETCWD	= $30		;get current directory (MyDOS/SpartaDOS)
+
+; Special Entry Command Equates
+; DOS Commands
+; Command line table, Index values for (DOSVEC),Y -- COMTAB
+; Compatible with OS/A+, DOS XL and SpartaDOS
+
+COMTAB  = 0             ;DOS entry jump vector
+ZCRNAME = 3             ;file name crunch routine jump vector
+BUFOFF  = 10            ;next parameter buffer offset
+COMFNAM = 33            ;destination buffer for crunch routine
+LBUF    = 63            ;command line input buffer
+
+; Screen IOCB Commands
 
 DRAWLN  = $11           ;draw line
 FILLIN  = $12           ;draw line with right fill
@@ -710,6 +735,9 @@ FPSCR1  = $05EC         ;6-byte floating point temporary
 
 ;LBFEND = $05FF         ;##old## END OF LBUFF
 
+
+DOS     = $0700
+
 ;-------------------------------------------------------------------------
 ; Cartridge Address Equates
 ;-------------------------------------------------------------------------
@@ -1022,29 +1050,6 @@ STOPLN  = $BA           ;2-byte stopped line number
 ERRSAVE = $C3           ;1-byte error code
 PTABW   = $C9           ;1-byte tab width
 
-;-------------------------------------------------------------------------
-; DOS
-;-------------------------------------------------------------------------
-
-DOS     = $0700
-
-RENAME  = $20           ;RENAME DISK FILE
-DELETE  = $21           ;DELETE DISK FILE
-LOCKFL  = $23           ;LOCK FILE TO READ ONLY
-UNLOCK  = $24           ;UNLOCK LOCKED FILE
-POINT   = $25           ;POINT SECTOR
-NOTE    = $26           ;NOTE SECTOR
-FORMAT  = $FE           ;FORMAT
-
-; Command line table, Index values for (DOSVEC),Y -- COMTAB
-; Compatible with OS/A+, DOS XL and SpartaDOS
-
-COMTAB  = 0             ;DOS entry jump vector
-ZCRNAME = 3             ;file name crunch routine jump vector
-BUFOFF  = 10            ;next parameter buffer offset
-COMFNAM = 33            ;destination buffer for crunch routine
-LBUF    = 63            ;command line input buffer
-
 ;-------------------------------------------------------------------------
 ; ATASCII CHARACTER DEFS
 ;-------------------------------------------------------------------------
diff --git a/libsrc/atari/initcwd.s b/libsrc/atari/initcwd.s
index 19df6a5a4..d7b574314 100644
--- a/libsrc/atari/initcwd.s
+++ b/libsrc/atari/initcwd.s
@@ -11,7 +11,7 @@
 
         jsr     findfreeiocb
         bne     oserr
-        lda     #48
+        lda     #GETCWD
         sta     ICCOM,x
         lda     #<__cwd
         sta     ICBLL,x
diff --git a/libsrc/atari/lseek.s b/libsrc/atari/lseek.s
index bf934294c..889976f5b 100644
--- a/libsrc/atari/lseek.s
+++ b/libsrc/atari/lseek.s
@@ -68,7 +68,7 @@ iocberr:jsr     incsp6
 
 ; SEEK_CUR
 cur:    ldx     tmp3
-        lda     #38             ; NOTE
+        lda     #NOTE
         sta     ICCOM,x
         jsr     CIOV            ; read it
         bmi     xxerr
@@ -84,7 +84,7 @@ l01:    lda     ICAX3,x         ; low byte of position
 
 ; SEEK_END
 end:    ldx     tmp3
-        lda     #39             ; get file size
+        lda     #GETFL
         sta     ICCOM,x
         jsr     CIOV
         bpl     l01
@@ -126,7 +126,7 @@ ret:    jsr     incsp6
 .if 0
         ; return exactly the position DOS has
         ldx     tmp3
-        lda     #38             ; NOTE
+        lda     #NOTE
         sta     ICCOM,x
         jsr     CIOV            ; read it
         bmi     xxerr
@@ -168,7 +168,7 @@ seek:   jsr     ldax0sp         ; get lower word of new offset
         sta     ICAX4,x
         lda     ptr4
         sta     ICAX5,x
-        lda     #37             ;POINT
+        lda     #POINT
         sta     ICCOM,x
         jsr     CIOV
         bpl     ret
@@ -201,7 +201,7 @@ chk_supp:
         cmp     #$40
         bcs     supp1           ; SD-X (ver 4.xx) supports seeking on all disks
         ldx     tmp3            ; iocb to use
-        lda     #39             ; get file size
+        lda     #GETFL
         sta     ICCOM,x
         jsr     CIOV
         bmi     notsupp         ; error code ? should be 168 (invalid command)
diff --git a/libsrc/atari/syschdir.s b/libsrc/atari/syschdir.s
index 9fc45edbd..16cb3a1fe 100644
--- a/libsrc/atari/syschdir.s
+++ b/libsrc/atari/syschdir.s
@@ -58,9 +58,9 @@ ucok1:
         lda     __dos_type
         cmp     #SPARTADOS
         beq     :+
-        lda     #41
+        lda     #CHDIR_MYDOS
         .byte   $2C             ; BIT <abs>
-:       lda     #44
+:       lda     #CHDIR_SPDOS
         sta     ICCOM,x
         lda     #0
         sta     ICAX1,x
diff --git a/libsrc/atari/sysmkdir.s b/libsrc/atari/sysmkdir.s
index de3252ced..56a068757 100644
--- a/libsrc/atari/sysmkdir.s
+++ b/libsrc/atari/sysmkdir.s
@@ -61,7 +61,7 @@ ucok1:
         sta     ICBAH,y
         tya
         tax
-        lda     #42
+        lda     #MKDIR
         sta     ICCOM,x
         lda     #8
         sta     ICAX1,x