diff --git a/src/AppleIISd.inc b/src/AppleIISd.inc
index 6736e65..99d9f6b 100644
--- a/src/AppleIISd.inc
+++ b/src/AppleIISd.inc
@@ -28,17 +28,16 @@ BLOCKNUM    :=    $46         ; block number
 
 
 ; Smartport
-SMPARAM     :=    $48         ; parameter count
-SMUNIT      :=    $49         ; unit number
-SMBUFF      :=    $4A         ; buffer pointer
-SMSTAT      :=    $4B         ; status / control code
-SMBLOCK     :=    $4C         ; block number
-SMCOUNT     :=    $4D         ; byte count
-SMADDR      :=    $4E         ; address for read
+SMPARAMLIST :=    $48         ; parameter list
+SMCMDLIST   :=    $4A         ; command list
+SMCSCODE    :=    $AC
+
+SMZPAREA    =     SMPARAMLIST
+SMZPSIZE    =     SMCSCODE-SMZPAREA+1
+SMCMD       =     DCMD
 
 
-
-; Ram equates
+; Ram equates, access with SLOT offset
 R30         :=    $0478
 R31         :=    $04F8
 R32         :=    $0578
diff --git a/src/AppleIISd.s b/src/AppleIISd.s
index 51e3f31..e3aff44 100644
--- a/src/AppleIISd.s
+++ b/src/AppleIISd.s
@@ -36,7 +36,7 @@
 
             .segment "SLOTID"
             .byt   $0         ; not extended, no SCSI, no RAM
-            .dbyt  $0         ; use status call
+            .word  $0000      ; use status call
             .byt   $97        ; Status bits
             .byt   <DRIVER    ; LSB of driver
 
@@ -53,8 +53,8 @@
             LDX   #$20
             LDX   #$00
             LDX   #$03
-;            LDX   #$00        ; is Smartport controller
-            LDX   #$3C
+            LDX   #$00        ; is Smartport controller
+;            LDX   #$3C
 
             SEI               ; find slot
             JSR   KNOWNRTS
@@ -82,6 +82,9 @@
 ;            INY
 ;            BPL   @DRAW
 
+;            LDA   #197      
+;            JSR   $FCA8       ; wait for 100 ms
+
 @OAPPLE:    BIT   OAPPLE      ; check for OA key
             BPL   @INIT       ; and skip boot if pressed
 
diff --git a/src/Smartport.s b/src/Smartport.s
index 4d74b13..4df19c7 100644
--- a/src/Smartport.s
+++ b/src/Smartport.s
@@ -20,21 +20,126 @@
 
 ;*******************************
 ;
-; Status request
-; $43    Unit number DSSS000
-; $44-45 Unused
-; $46-47 Unused
+; Smartport command dispatcher
+;
+; $42-$47 MLI input locations
+; X Slot*16
+; Y Slot
 ;
 ; C Clear - No error
 ;   Set   - Error
 ; A $00   - No error
-;   $2B   - Card write protected
-;   $2F   - No card inserted
-; X       - Blocks avail (low byte)
-; Y       - Blocks avail (high byte)
+;   $01   - Unknown command
 ;
 ;*******************************
 
-SMARTPORT:  PLA               ; pull return address
-            TAY
-         
\ No newline at end of file
+SMARTPORT:  LDY   #SMZPSIZE-1   ; save zeropage area for Smarport
+@SAVEZP:    LDA   SMZPAREA,Y
+            PHA
+            DEY
+            BPL   @SAVEZP
+
+            TSX                 ; get parameter list pointer
+            LDA   $101+SMZPSIZE,X
+            STA   SMPARAMLIST
+            CLC
+            ADC   #3            ; adjust return address
+            STA   $101+SMZPSIZE,X
+            LDA   $102+SMZPSIZE,X
+            STA   SMPARAMLIST+1
+            ADC   #0
+            STA   $102+SMZPSIZE,X
+
+            LDY   #1            ; get command code
+            LDA   (SMPARAMLIST),Y 
+            STA   SMCMD
+            INY
+            LDA   (SMPARAMLIST),Y
+            TAX
+            INY
+            LDA   (SMPARAMLIST),Y
+            STA   SMPARAMLIST+1 ; TODO: why overwrite, again?
+            STX   SMPARAMLIST
+
+            LDA   #ERR_BADCMD   ; suspect bad command
+            LDX   SMCMD
+            CPX   #$09+1        ; command too large
+            BCS   @END
+
+            LDA   (SMPARAMLIST) ; parameter count
+            CMP   REQPARAMCOUNT,X
+            BNE   @COUNTMISMATCH
+
+            LDY   #1            ; get drive number
+            LDA   (SMPARAMLIST),Y
+            LDY   SLOT
+            STA   DRVNUM,Y
+
+            TXA
+            ASL   A             ; shift for use or word addresses
+            TAX
+            JSR   @JMPSPCOMMAND
+            BCS   @END          ; jump on error
+            LDA   #NO_ERR
+
+@END:       TAX                 ; save retval
+            LDY   #0            ; restore zeropage
+@RESTZP:    PLA
+            STA   SMZPAREA,Y
+            INY
+            CPY   #SMZPSIZE
+            BCC   @RESTZP
+
+            TXA
+            LDY   #2            ; highbyte of # bytes transferred
+            LDY   #0            ; low byte of # bytes transferred
+            CMP   #1            ; C=1 if A != NO_ERR
+            RTS
+
+@COUNTMISMATCH:
+            LDA   #ERR_BADPCNT
+            BRA   @END
+            
+@JMPSPCOMMAND:                  ; use offset from cmd*2
+            JMP   (SPDISPATCH,X)
+            
+
+
+; Required parameter counts for the commands
+REQPARAMCOUNT:
+            .byt 3              ; 0 = status
+            .byt 3              ; 1 = read block
+            .byt 3              ; 2 = write block
+            .byt 1              ; 3 = format
+            .byt 3              ; 4 = control
+            .byt 1              ; 5 = init
+            .byt 1              ; 6 = open
+            .byt 1              ; 7 = close
+            .byt 4              ; 8 = read char
+            .byt 4              ; 9 = write char
+
+; Command jump table
+SPDISPATCH:
+            .word SMSTATUS
+            .word SMREADBLOCK
+            .word SMWRITEBLOCK
+            .word SMFORMAT
+            .word SMCONTROL
+            .word SMINIT
+            .word SMOPEN
+            .word SMCLOSE
+            .word SMREADCHAR
+            .word SMWRITECHAR
+
+
+
+SMSTATUS:
+SMREADBLOCK:
+SMWRITEBLOCK:
+SMFORMAT:
+SMCONTROL:
+SMINIT:
+SMOPEN:
+SMCLOSE:
+SMREADCHAR:
+SMWRITECHAR:
\ No newline at end of file