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@@ -166,6 +166,48 @@ Define TARGET_IS_TM4C129_RA0 (#define TARGET_IS_TM4C129_RA0) at the beginning of
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+
+== While executing an RTOS program I get a very cryptic and long error message about an exception called `E_hardfault` like below. What shall I do?
+
+----
+ti.sysbios.family.arm.m3.Hwi: line 1095: E_hardFault: FORCED
+ti.sysbios.family.arm.m3.Hwi: line 1172: E_busFault: IMPRECISERR: Delayed Bus Fault, exact addr unknown, address: e000ed38
+Exception occurred in ISR thread at PC = 0x0002f6ec.
+Core 0: Exception occurred in ThreadType_Hwi.
+Hwi name: {unknown-instance-name}, handle: 0x20000408.
+Hwi stack base: 0x2002a3f8.
+Hwi stack size: 0x2000.
+R0 = 0x87200746 R8 = 0x0003b3d4
+R1 = 0x2002c308 R9 = 0xffffffff
+R2 = 0x00000002 R10 = 0xffffffff
+R3 = 0x2002c344 R11 = 0xffffffff
+R4 = 0x0002b51d R12 = 0x2002a388
+R5 = 0x00000000 SP(R13) = 0x2002c308
+R6 = 0x00000001 LR(R14) = 0x0002f6e9
+R7 = 0x00000001 PC(R15) = 0x0002f6ec
+PSR = 0x81000043
+ICSR = 0x00423003
+MMFSR = 0x00
+BFSR = 0x04
+UFSR = 0x0000
+HFSR = 0x40000000
+DFSR = 0x0000000b
+MMAR = 0xe000ed34
+BFAR = 0xe000ed38
+AFSR = 0x00000000
+Terminating execution...
+----
+
+You can basically treat this case as a segmentation fault (segfault) on the PC.
+The most probably reason for the error is that you misused a pointer variable or told RTOS to read from a wrong address (by passing wrong parameters to one of its functions).
+
+Unlike ordinary PC OSes the TI-RTOS gives you much more information in such cases and in theory you can decode all that information by following the instructions in TI's guide on this topic: link:http://www.ti.com/lit/an/spma043/spma043.pdf[Diagnosing Software Faults in Stellaris Microcontrollers].
+
+However, this is usually overkill because you don't need nor want to deal with that much information.
+What you usually need to do is simply fix your pointers by using the debugger.
+Especially check for NULL pointer dereferences!
+
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