Roland DIF-AT: Difference between revisions

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==Extract Firmware==

At some point in the repair attempt, I heard a strange flapping sound from the NOR Flash as I moved the device around. ALL of the pins 25 - 48 had detached from the PCB with zero damage to the traces or pins. I surmise that this was the original failure point of the device - dry joints on the Flash chip.

After I desoldered the other half using hot air, I could proceed to read out the contents -

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=== TL48 Programmer- ===

I used a TL48 programmer with a 48pin TTSOP to read the NOR Flash firmware contents -

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The strings are very interesting indeed. Not just a standard 'version' or 'release date' string - they are command strings!

As this device has no screen, a low level diagnostic routine is inferred from their discovery. Looking closely at the last string or two, I was worried that it might be corrupted as there are some missing letters in the string - (ADAT Sync port di onnected and Dectected rather than Detected).

[[File:DIF AT FLASH SETTINGS.png|thumb|T48 programmer settings and dump - note the very interesting strings!]]

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=== Binwalk / Binvis ===

I slowed down a bit here because I had no idea how to actually load the file I'd dumped to look at it. First I used Binwalk, which isn't so well suited to this task. Anyway he was able to provide a nice image showing the entropy of the file - low entropy = low chance of corruption or encryption.

I also had a look in Binvis. Binvis makes for a stunning visual representation even if its not useful in any other way. It was fun to see the strings represented in coloured pixels.

@@ Line 92: / Line 92: @@
 <br />
 ==Extract Firmware==
+At some point in the repair attempt, I heard a strange flapping sound from the NOR Flash as I moved the device around.  ALL of the pins 25 - 48 had detached from the PCB with zero damage to the traces or pins.  I surmise that this was the original failure point of the device - dry joints on the Flash chip.
+After I desoldered the other half using hot air, I could proceed to read out the contents -
+<br />
+=== TL48 Programmer- ===
 I used a TL48 programmer with a 48pin TTSOP to read the NOR Flash firmware contents -
@@ Line 102: / Line 109: @@
 The strings are very interesting indeed.  Not just a standard 'version' or 'release date' string - they are command strings!
 As this device has no screen, a low level diagnostic routine is inferred from their discovery.  Looking closely at the last string or two, I was worried that it might be corrupted as there are some missing letters in the string - (ADAT Sync   port di  onnected and Dectected rather than Detected).
 [[File:DIF AT FLASH SETTINGS.png|thumb|T48 programmer settings and dump - note the very interesting strings!]]
+<br />
+=== Binwalk / Binvis ===
+I slowed down a bit here because I had no idea how to actually load the file I'd dumped to look at it.  First I used Binwalk, which isn't so well suited to this task.  Anyway he was able to provide a nice image showing the entropy of the file - low entropy = low chance of corruption or encryption.
+I also had a look in Binvis.  Binvis makes for a stunning visual representation even if its not useful in any other way.  It was fun to see the strings represented in coloured pixels.