1 files changed, 44 insertions, 0 deletions
diff --git a/nuttx/configs/open1788/README.txt b/nuttx/configs/open1788/README.txt
index 59fc1f9d3..167c92f98 100644
--- a/nuttx/configs/open1788/README.txt
+++ b/nuttx/configs/open1788/README.txt
@@ -346,6 +346,50 @@ CONFIGURATION
        load objects twice to account for write failures.  I have not yet
        found a simple foolproof way to reliably get the code into FLASH.
 
+    4. Combining .hex files.  If you plan to use the .hex files with your
+       debugger or FLASH utility, then you may need to combine the two hex
+       files into a single .hex file.  Here is how you can do that.
+
+       a. The 'tail' of the nuttx.hex file should look something like this
+          (with my comments added):
+
+            $ tail nuttx.hex
+            # 00, data records
+            ...
+            :10 9DC0 00 01000000000800006400020100001F0004
+            :10 9DD0 00 3B005A0078009700B500D400F300110151
+            :08 9DE0 00 30014E016D0100008D
+            # 05, Start Linear Address Record
+            :04 0000 05 0800 0419 D2
+            # 01, End Of File record
+            :00 0000 01 FF
+
+          Use an editor such as vi to remove the 05 and 01 records.
+
+       b. The 'head' of the nuttx_user.hex file should look something like
+          this (again with my comments added):
+
+            $ head nuttx_user.hex
+            # 04, Extended Linear Address Record
+            :02 0000 04 0801 F1
+            # 00, data records
+            :10 8000 00 BD89 01084C800108C8110208D01102087E
+            :10 8010 00 0010 00201C1000201C1000203C16002026
+            :10 8020 00 4D80 01085D80010869800108ED83010829
+            ...
+
+          Nothing needs to be done here.  The nuttx_user.hex file should
+          be fine.
+
+       c. Combine the edited nuttx.hex and un-edited nuttx_user.hex
+          file to produce a single combined hex file:
+
+          $ cat nuttx.hex nuttx_user.hex >combined.hex
+
+       Then use the combined.hex file with the to write the FLASH image.
+       If you do this a lot, you will probably want to invest a little time
+       to develop a tool to automate these steps.
+
   nsh
   ---
     Configures the NuttShell (nsh) located at examples/nsh.  The