X-Git-Url: https://hackdaworld.org/gitweb/?p=my-code%2Farm.git;a=blobdiff_plain;f=betty%2Fstartup.s;fp=betty%2Fstartup.s;h=bc4ff4177c5c87ca1102cf705f5668c5454ae78b;hp=0000000000000000000000000000000000000000;hb=21b21d3d5c7feb1ece4c8ea3d495e03c502450ea;hpb=cc9a44bee2152e887691958d3580e17ef15810e2

diff --git a/betty/startup.s b/betty/startup.s
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+#
+# startup.s - starup code for the lpc2220
+#
+# author: hackbard@hackdaworld.org
+#
+
+#
+# some definitions
+#
+
+# sram
+
+.equ	sram_size,	(64*1024)
+.equ	sram_addr,	0x40000000
+.equ	sram_top,	(sram_addr+sram_size-4)
+
+# stack
+
+.equ	stack_size,	(2*1024)
+.equ	stack_top,	sram_top
+.equ	stack_limit,	(sram_top-stack_size)
+
+#
+# the startup code
+#
+
+.text
+.arm
+
+	# init stack pointer
+
+	ldr r0, =sram_top
+	mov sp, r0
+	ldr r0, =stack_limit
+	mov sl, r0
+
+	# jump to c code
+
+	adr lr, loop_forever
+	mov r0, #0
+	mov r1, #0
+	ldr r2, =main
+	bx r2
+
+loop_forever:
+	b loop_forever
+