1 files changed, 25 insertions, 0 deletions
diff --git a/cpu/os.asm b/cpu/os.asm
new file mode 100644
index 0000000..5d58ff7
--- /dev/null
+++ b/cpu/os.asm
@@ -0,0 +1,25 @@
+.text
+init:
+    li B _clock
+    lw B 0(B)
+    jz B init
+    add D D B
+    push D
+    li A msgtick
+    jal ser_out_msg
+    pop D
+    j init
+
+ser_out_msg:
+    li C _output
+ser_out_msg_loop:
+    lb B 0(A)
+    jz B ser_out_msg_ret
+    sb B 0(C)
+    incri A 1
+    j ser_out_msg_loop
+ser_out_msg_ret:
+    jr RA
+
+msgtick:
+    ascii "Tick!"