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→Binwalk / Binvis -
==Examine Firmware -==
===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 [https://github.com/ReFirmLabs/binwalk Binwalk], which I *think* is more suited to SOC work (at least, I think Binwalk is able to find files and systems within bin images, which this firmware does not contain) Anyway Binwalk was able to provide an informative image showing the entropy of the file - low entropy = low chance of corruption or encryption.
=== Binvis - ===I also had a look at [https://binvis.io/ Binvis]. Binvis makes for a stunning visual representation, regardless of anything else at all. I love it. It was fun to see the strings represented in coloured pixels. Also, very apparent to see in Binvis, are the firmware banks. [[File:Binwalk entropy image.png|left|thumb|Binwalk entropy image looking good - encouraging at least]][[File:DIF-AT BINVIS.png|alt=binvis.io|center|thumb|BINVIS The little 'white line defined' area is where the pointer is viewing]][[File:Binwalk entropy image.png|thumb|Binwalk entropy image looking good - encouraging at least|alt=|none]]
===Firmware Banks -===
This firmware is banked and split. This is to facilitate DFU - the device can be firmware updated by the user while still maintaining stable OS. Then switch a flag to change/denote active bank.
Probably some of these are the as yet un-mapped SRAM, and Alesis IC addresses. I've added peripheral mapping for the SCI. I'm learning a lot as I go! Also maybe the Alesis ASIC remaps certain memory addresses at run time? (more research has shown that this is likely). These images show the mirrored banked addresses - some lead to empty regions (maybe ram?) and some have near identical code (version differences?) and some have different data (bytes table for strings) [[File:DIF-ATBanked ROM2.png.png|thumb|DIF-AT firmware showing mirrored 'blank' bank location. |alt=]][[File:DIFAT Bank Example.png|alt=DIF-AT firmware with mirrored bank -near identical addressing much higher in ROM region|thumb|DIF-AT firmware with mirrored bank - almost identical addressing just much higher in ROM region|none]]
== Firmware Strings - ==
Alright we've heard enough about them; here is the list - '''''strings -n 6 INTEL_HEX_DIF_AT_LH28F400BVE@TSOP48_byte_swapped.bin'''''
{| class="wikitable sortable"