diff --git a/ui/ui_dbg.h b/ui/ui_dbg.h
index 98d23f67..d3a1c1c0 100644
--- a/ui/ui_dbg.h
+++ b/ui/ui_dbg.h
@@ -1449,9 +1449,9 @@ void _ui_dbg_draw_regs(ui_dbg_t* win) {
         char f_str[9] = {
             (c->f & Z80_SF) ? 'S':'-',
             (c->f & Z80_ZF) ? 'Z':'-',
-            (c->f & Z80_YF) ? 'X':'-',
+            (c->f & Z80_YF) ? 'Y':'-',
             (c->f & Z80_HF) ? 'H':'-',
-            (c->f & Z80_XF) ? 'Y':'-',
+            (c->f & Z80_XF) ? 'X':'-',
             (c->f & Z80_VF) ? 'V':'-',
             (c->f & Z80_NF) ? 'N':'-',
             (c->f & Z80_CF) ? 'C':'-',
diff --git a/ui/ui_z80.h b/ui/ui_z80.h
index d24e28c2..ab8787d1 100644
--- a/ui/ui_z80.h
+++ b/ui/ui_z80.h
@@ -8,11 +8,11 @@
     ~~~C
     #define CHIPS_UI_IMPL
     ~~~
-    before you include this file in *one* C++ file to create the 
+    before you include this file in *one* C++ file to create the
     implementation.
 
     Optionally provide the following macros with your own implementation
-    
+
     ~~~C
     CHIPS_ASSERT(c)
     ~~~
@@ -47,7 +47,7 @@
         2. Altered source versions must be plainly marked as such, and must not
         be misrepresented as being the original software.
         3. This notice may not be removed or altered from any source
-        distribution. 
+        distribution.
 #*/
 #include <stdint.h>
 #include <stdbool.h>
@@ -134,9 +134,9 @@ static void _ui_z80_regs(ui_z80_t* win) {
     char f_str[9] = {
         (f & Z80_SF) ? 'S':'-',
         (f & Z80_ZF) ? 'Z':'-',
-        (f & Z80_YF) ? 'X':'-',
+        (f & Z80_YF) ? 'Y':'-',
         (f & Z80_HF) ? 'H':'-',
-        (f & Z80_XF) ? 'Y':'-',
+        (f & Z80_XF) ? 'X':'-',
         (f & Z80_VF) ? 'V':'-',
         (f & Z80_NF) ? 'N':'-',
         (f & Z80_CF) ? 'C':'-',