diff --git a/cfg/atmos.cfg b/cfg/atmos.cfg
index 5bb61bb26..a1f935efa 100644
--- a/cfg/atmos.cfg
+++ b/cfg/atmos.cfg
@@ -23,8 +23,8 @@ SEGMENTS {
     RODATA:   load = RAM,     type = ro;
     INIT:     load = RAM,     type = ro,  define = yes, optional = yes;
     DATA:     load = RAM,     type = rw;
-    ZPSAVE1:  load = RAM,     type = rw,  define = yes;
-    ZPSAVE2:  load = RAM,     type = bss;
+    ZPSAVE1:  load = RAM,     type = rw,  define = yes; # ZPSAVE1, ZPSAVE2 must be together
+    ZPSAVE2:  load = RAM,     type = bss;               # see "libsrc/atmos/crt0.s"
     BSS:      load = RAM,     type = bss, define = yes;
 }
 FEATURES {
diff --git a/libsrc/atmos/crt0.s b/libsrc/atmos/crt0.s
index ecbc00391..61f40cc9a 100644
--- a/libsrc/atmos/crt0.s
+++ b/libsrc/atmos/crt0.s
@@ -92,6 +92,9 @@ zpsave:
 
         .byte   0
 
+; The segments "ZPSAVE1" and "ZPSAVE2" always must be together.
+; They create a single object (the zpsave buffer).
+
 .segment        "ZPSAVE2"
 
         .res    zpspace - 1