SXB: support rom loader as system fcode

platforms/W65C816SXB/platform-config.inc

@@ -1 +1,5 @@
+; Should we inclide the romloader in $SXB-ROMLDR
+.define romloader_as_word 0
 
+; Should we instead put it in the FCode to install at startup?
+.define romloader_at_init 1

platforms/W65C816SXB/platform-lib.s

@@ -260,12 +260,28 @@ wait:     phx                   ; note 8-bit mode!
           jmp   _sf_success
 .endproc
 
-.proc     _sf_fcode             ; none for now
+.proc     _sf_fcode
+.if include_fcode
+          ldy   #.loword(list)
+          lda   #.hiword(list)
+.else
           lda   #$0000
           tay
+.endif
           plx
           jsr   _pushay
           jmp   _sf_success
+.if include_fcode
+list:
+  .if romloader_at_init
+          .dword romldr
+  .endif
+          .dword 0
+  .if romloader_at_init
+romldr:   PLATFORM_INCBIN "fcode/romloader.fc"
+  .endif
+.endif
+
 .endproc
 
 ; SXB really can't do this when ROM is banked out.  Maybe restart Forth instead?

platforms/W65C816SXB/platform-words.s

@@ -44,7 +44,7 @@ dword     dCPU_HZ,"$CPU_HZ"
           FCONSTANT cpu_clk
 eword
 
-.if include_fcode ; SXB stuff, should do different
+.if include_fcode && romloader_as_word ; SXB stuff, should do different
 dword     SXB_ROMLDR,"$SXB-ROMLDR"
           ENTER
           ONLIT :+