Merged my changes

There you have it!

emunand/emuCodeo3ds.s

@@ -0,0 +1,50 @@
+.nds
+
+sdmmc equ 0x434D4453	;dummy
+
+.create "emunand.bin", 0x0801A4C0
+.org 0x0801A4C0
+.arm
+nand_sd:
+    ; Original code that still needs to be executed.
+    mov r4, r0
+    mov r5, r1
+    mov r7, r2
+    mov r6, r3
+    ; End.
+
+    ; If we're already trying to access the SD, return.
+    ldr r2, [r0, #4]
+    ldr r1, =sdmmc
+    cmp r2, r1
+    beq nand_sd_ret
+
+    str r1, [r0, #4]  ; Set object to be SD
+    ldr r2, [r0, #8]  ; Get sector to read
+    cmp r2, #0  ; For GW compatibility, see if we're trying to read the ncsd header (sector 0)
+
+    ldr r3, =nand_offset
+    ldr r3, [r3]
+    add r2, r3  ; Add the offset to the NAND in the SD.
+
+    ldreq r3, =ncsd_header_offset
+    ldreq r3, [r3]
+    addeq r2, r3  ; If we're reading the ncsd header, add the offset of that sector.
+
+    str r2, [r0, #8]  ; Store sector to read
+
+    nand_sd_ret:
+        ; Restore registers.
+        mov r1, r5
+        mov r2, r7
+        mov r3, r6
+
+        ; Return 4 bytes behind where we got called,
+        ;   due to the offset of this function being stored there.
+        mov r0, lr
+        add r0, #4
+        bx r0
+.pool
+nand_offset:		.ascii "NAND"       ; for rednand this should be 1
+ncsd_header_offset:	.ascii "NCSD"       ; depends on nand manufacturer + emunand type (GW/RED)
+.close