diff --git a/tests/psoc6/flash.py b/tests/psoc6/flash.py
index fdac69bb855bd..b75771af4e67f 100644
--- a/tests/psoc6/flash.py
+++ b/tests/psoc6/flash.py
@@ -7,6 +7,7 @@
 os.umount("/")
 
 test_string = "This is a test string."
+long_test_string = "This is a very long string. And as a long string that it is, it is only getting longer and longer and the string goes. How long shall it be? Well, not really sure, but let´s try it like this."
 print(test_string)
 
 # first priority is always LFS2 filesystem as it is the default
@@ -37,6 +38,17 @@
         print("Test successful")
     f.close()
 
+    # open a file and do some operation
+    f = open("/flash/test_lfs2_2.txt", "w")
+    f.write(long_test_string)
+    f.close()
+
+    # read back the contents
+    f = open("/flash/test_lfs2_2.txt", "r")
+    if f.read() == long_test_string:
+        print("Test successful")
+    f.close()
+
 if "VfsFat" in dir(os):
     # create a FAT fs and mount it, else format and mount it
     try:
@@ -57,3 +69,14 @@
     if f.read() == test_string:
         print("Test successful")
     f.close()
+
+    # open a file and do some operation
+    f = open("/flash/test_fat_2.txt", "w")
+    f.write(long_test_string)
+    f.close()
+
+    # read back the contents
+    f = open("/flash/test_fat_2.txt", "r")
+    if f.read() == long_test_string:
+        print("Test successful")
+    f.close()
diff --git a/tests/psoc6/flash.py.exp b/tests/psoc6/flash.py.exp
index ebf73f8bf0104..fe356ae4991d4 100644
--- a/tests/psoc6/flash.py.exp
+++ b/tests/psoc6/flash.py.exp
@@ -1,2 +1,3 @@
 This is a test string.
 Test successful
+Test successful