diff --git a/board/sandbox/README.sandbox b/board/sandbox/README.sandbox
index 0f59da4..9b09404 100644
--- a/board/sandbox/README.sandbox
+++ b/board/sandbox/README.sandbox
@@ -422,7 +422,19 @@
 Note that many of these tests are implemented as commands which you can
 run natively on your board if desired (and enabled).
 
-It would be useful to have a central script to run all of these.
+To run all tests use "make check".
+
+
+Memory Map
+----------
+
+Sandbox has its own emulated memory starting at 0. Here are some of the things
+that are mapped into that memory:
+
+      0   CONFIG_SYS_FDT_LOAD_ADDR   Device tree
+   e000   CONFIG_BLOBLIST_ADDR       Blob list
+  10000   CONFIG_MALLOC_F_ADDR       Early memory allocation
+
 
 --
 Simon Glass <sjg@chromium.org>