diff --git a/apple2/apple2gs/bus/sp_control.asm b/apple2/apple2gs/bus/sp_control.asm
index 9ed931e..4ab67e2 100644
--- a/apple2/apple2gs/bus/sp_control.asm
+++ b/apple2/apple2gs/bus/sp_control.asm
@@ -25,6 +25,7 @@ error           equ 5
                 plb
 
                 lda     #SP_CONTROL_PARAM_COUNT
+                ldy     #SP_PAYLOAD_SIZE        cmdlist offset
                 short   m
                 sta     [fwdata_ptr],y
                 long    m