1 files changed, 69 insertions, 0 deletions
diff --git a/init_low.s b/init_low.s
new file mode 100644
index 0000000..bd7f329
--- /dev/null
+++ b/init_low.s
@@ -0,0 +1,69 @@
+/*
+https://github.com/dwelch67/stm32_samples
+http://stackoverflow.com/questions/9565921/cortex-m3-initialisation
+*/
+
+.syntax unified
+.cpu cortex-m3
+.thumb
+
+.section .isr_vectors
+
+.global vectors
+vectors:
+stacktop: .word 0x20001000
+.word _Reset_Handler
+.word NMI_Handler
+.word HardFault_Handler
+.word MemManage_Handler
+.word BusFault_Handler
+.word UsageFault_Handler
+.word halt
+.word halt
+.word halt
+.word halt
+.word halt
+.word halt
+.word halt
+.word halt
+.word halt
+
+/* VERY significant */
+.section .text
+
+.thumb_func
+.global _Reset_Handler
+_Reset_Handler:
+    bl init_high
+    b halt
+
+.thumb_func
+.global halt
+halt:
+    b .
+
+.thumb_func
+NMI_Handler:
+    b halt
+
+.thumb_func
+HardFault_Handler:
+    tst lr, #4
+    ite eq
+    mrseq r0, msp
+    mrsne r0, psp
+    b HardFault_Handler_C
+
+.thumb_func
+MemManage_Handler:
+    b halt
+
+.thumb_func
+BusFault_Handler:
+    b halt
+
+.thumb_func
+UsageFault_Handler:
+    b halt
+
+.end