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authorNao Pross <naopross@thearcway.org>2018-10-30 11:41:24 +0100
committerNao Pross <naopross@thearcway.org>2018-10-30 11:41:24 +0100
commit43be150dc6e84f6f6eeb071cd3cdb7fc21125d60 (patch)
tree541fd3d690c1bdfd7b68d684029a400b80f4aa06 /sw-old/z80/tests/usart/crt0.s
parentAdd datasheets for ATmega328 and 74LS259 (diff)
downloadz80uPC-43be150dc6e84f6f6eeb071cd3cdb7fc21125d60.tar.gz
z80uPC-43be150dc6e84f6f6eeb071cd3cdb7fc21125d60.zip
Move sw to sw-old and hw to hw-altium, add kicad files
Diffstat (limited to 'sw-old/z80/tests/usart/crt0.s')
-rw-r--r--sw-old/z80/tests/usart/crt0.s38
1 files changed, 38 insertions, 0 deletions
diff --git a/sw-old/z80/tests/usart/crt0.s b/sw-old/z80/tests/usart/crt0.s
new file mode 100644
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--- /dev/null
+++ b/sw-old/z80/tests/usart/crt0.s
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+ .module crt0
+ .area _HEADER (ABS)
+
+;; Reset vectors
+ .org 0
+ jp init
+
+ .org 0x38 ; the instruction 0xff (not written) resets to this location
+ jp init
+
+;; main code
+ .org 0x100
+ .globl _main
+
+init:
+ ;; Set stack pointer directly above top of memory.
+ ld sp,#0xffff
+
+ ;; Start of the program
+ call _main
+ jp _exit
+
+_exit:
+ halt
+ ; jp _exit
+
+;; Ordering of segments for the linker.
+ .area _HOME
+ .area _CODE
+ .area _INITIALIZER
+ .area _GSINIT
+ .area _GSFINAL
+
+ .area _DATA
+ .area _INITIALIZED
+ .area _BSEG
+ .area _BSS
+ .area _HEAP