diff --git a/internal_filesystem/lib/mpos/main.py b/internal_filesystem/lib/mpos/main.py
index 77401bcd..dc4270d0 100644
--- a/internal_filesystem/lib/mpos/main.py
+++ b/internal_filesystem/lib/mpos/main.py
@@ -110,13 +110,14 @@ def detect_board():
             if single_address_i2c_scan(i2c0, 0x6B): # IMU (plus possibly the Communicator's LANA TNY at 0x38)
                 return "fri3d_2024"
 
-        print("odroid_go ?")
-        if check_pins(0, 13, 27, 39): # this matches too much (also fri3d_2024) so move towards the end
-            return "odroid_go"
+        import machine
+        if machine.unique_id()[0] == 0xdc: # prototype board had: dc:b4:d9:0b:7d:80
+            # or: if single_address_i2c_scan(i2c0, 0x6A): # IMU currently not installed on prototype board
+            return "fri3d_2026"
 
-        print("Fallback to fri3d_2026")
-        # default: if single_address_i2c_scan(i2c0, 0x6A): # IMU but currently not installed
-        return "fri3d_2026"
+        print("odroid_go ?")
+        #if check_pins(0, 13, 27, 39): # not good because it matches other boards (like fri3d_2024 and fri3d_2026)
+        return "odroid_go"
 
 # EXECUTION STARTS HERE