Fix link_loop writing addresses instead of IDs

kernel/ipc.z80

@@ -52,7 +52,7 @@ ld b, 0
 ret
 
 .global mb_read
-;Reads a meddage from the MB specified in HL,
+;Reads a message from the MB specified in HL,
 ; and returns the pointer in C:DE:HL. 
 ; Returns 0 in B if the mailbox had a message, and 1 if it was full
 mb_read: 
@@ -118,24 +118,22 @@ ld (mb_next_frame_num), bc
 call get_mb_ptr
 push hl
 pop ix
+pop hl
 push hl
-pop iy
+inc hl
+/* push hl */
+/* pop iy */
 link_loop:
-inc iyh
-ld a, iyh
-cp 0xf0
-jp nz, iy_ok
+ld (ix + 0), l
+ld (ix + 1), h
+inc hl
+inc ixh
+ld a, ixh
+cp 0xef
+jp nz, link_loop
+link_loop_done:
 ld (ix + 0), 0
 ld (ix + 1), 0
-jp link_loop_done
-iy_ok:
-push iy
-pop bc
-ld (ix + 0), c
-ld (ix + 1), b
-inc ixh
-jp link_loop
-link_loop_done:
 pop hl
 ld (mb_free_list), hl
 ld bc, (mb_free_list)
@@ -154,9 +152,10 @@ pop ix
 ld a, (ix + 0)
 ld (mb_free_list), a
 ld a, (ix + 1)
-ld (mb_free_list), a
+ld (mb_free_list + 1), a
 ld hl, (temp)
 ret
+
 ; Clobbers A, BC, DE, and IX
 get_mb_ptr:
 ld a, h