basic implemtation general purpose clock and tinyprintf

[cortex-from-scratch] / start.asm

diff --git a/start.asm b/start.asm
index 294a718..180f9a4 100644 (file)
--- a/start.asm
+++ b/start.asm
@@ -1,4 +1,13 @@
-       .equ STACK_TOP, 0x20000800
+/* (CC-BY-NC-SA) ROBIN KRENS - ROBIN @ ROBINKRENS.NL
+ * 
+ * $LOG$
+ * 2019/7/20 - ROBIN KRENS     
+ * Initial version 
+ * 
+ * $DESCRIPTION$
+ *
+ * */
+       .equ STACK_TOP, 0x20010000 /* placed at 64kB, top of SRAM */
        .text
        .global _start
        .global reset, nmi, hardfault
@@ -27,14 +36,12 @@ hardfault:
        b hardfault
 .global stub
 stub:
-       mov r1, #'z'
-       ldr r0, [r1]
-       bx lr
-       /* ldr R0,=10
+       ldr R0,=10
        mov R1,#0
-       udiv.w R2, R0, R1 */
+       ldc2 11, cr0, [r1, #4]
+       udiv.w R2, R0, R1 
 
        .data
-       .word 'x'
+       .word 'x' 
        .end