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+
+Memory Utilization
+=====================
+
+`text` is what ends up in flash (only).
+`data` is initialized variables: need to be storad in flash, then end up in RAM.
+`bss` is uninitialized data: nothing in flash, but does consume RAM.
+
+The `-x --format=sysv` flags to `arm-none-eabi-size` can be helpful.
+
+Debugging
+================
+
+Access all registers:
+
+    (gdb) x/x 0xE000ED14 
+    0xe000ed14:     Cannot access memory at address 0xe000ed14
+    (gdb) 
+    0xe000ed18:     Cannot access memory at address 0xe000ed18
+    (gdb) show mem inaccessible-by-default
+    Unknown memory addresses will be treated as inaccessible.
+    (gdb) set mem inaccessible-by-default off
+    (gdb) x/x 0xE000ED14 
+    0xe000ed14:     0x00000200
+
+Uploading via SWD
+====================
+
+`upload_blackmagic.sh`:
+
+    #!/bin/bash
+    arm-none-eabi-gdb build/stm32f401cc_project.elf < load_blackmagic.gdb
+    sleep 1.0
+
+`load_blackmagic.gdb`:
+
+    target extended-remote /dev/ttyACM0
+    monitor swdp_scan
+    attach 1
+    load
+    quit
+
+References
+=============
+
+Keil Application Note 209: Using Cortex-M3 and Cortex-M4 Fault Exceptions
+
+ARM Cortex-M3 HardFault Status Register Documentation:
+<http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0553a/Cihdjcfc.html>
+
+"STM32/ARM Cortex-M3 HOWTO: Development under Ubuntu (Debian)" (from fun-tech.se:
+<http://fun-tech.se/stm32/)>