Dir cleanup

src/writefloppy.asm

@@ -0,0 +1,32 @@
+BITS 16
+CPU 8086
+
+start:
+
+; sp and all segment registers need to be saved
+push bp             ; and we also save bp (??)
+push es
+mov bp, sp          ; we'll need that to access parameters
+
+xor dx, dx          ; drive 0, head 0
+mov es, dx          ; es = 0
+
+mov bx, 0xf000      ; store the read sector there
+mov ax, 0x0301      ; write, 1 sector
+
+; params: cylinder, head, sector, out
+mov si, [bp+14]
+mov ch, [si]
+mov si, [bp+12]
+mov dh, [si]
+mov si, [bp+10]
+mov cl, [si]
+
+int 0x13
+
+mov si, [bp+8]
+mov [si], ax
+
+pop es
+pop bp
+retf 8              ; 2x the number of parameters on the stack