From 94653e5c8ccf9b70e913cc00c114e2cffe623fe0 Mon Sep 17 00:00:00 2001
From: Irmen de Jong <irmen@razorvine.net>
Date: Mon, 24 Feb 2025 23:07:51 +0100
Subject: [PATCH] possible workaround for SMC issue that could make
 sys.reset_system() and sys.poweroff_system() not work properly

---
 compiler/res/prog8lib/cx16/syslib.p8 | 13 +++++++++----
 docs/source/todo.rst                 |  1 -
 examples/test.p8                     | 12 +++---------
 3 files changed, 12 insertions(+), 14 deletions(-)

diff --git a/compiler/res/prog8lib/cx16/syslib.p8 b/compiler/res/prog8lib/cx16/syslib.p8
index 5af03be38..f34a0bb61 100644
--- a/compiler/res/prog8lib/cx16/syslib.p8
+++ b/compiler/res/prog8lib/cx16/syslib.p8
@@ -1363,7 +1363,7 @@ _continue   iny
 
     sub poweroff_system() {
         ; -- use the SMC to shutdown the computer
-        void cx16.i2c_write_byte($42, $01, $00)
+        sys.poweroff_system()
     }
 
     sub set_led_state(bool on) {
@@ -1530,16 +1530,21 @@ asmsub  set_rasterline(uword line @AY) {
         ; (note: this is an asmsub on purpose! don't change into a normal sub)
         %asm {{
             sei
-            ldx #$42
+-           ldx #$42
             ldy #2
             lda #0
-            jmp  cx16.i2c_write_byte
+            jsr  cx16.i2c_write_byte
+            bra  -      ; to work around an issue where the routine does not in fact immediately reset the system
+            ; !notreached!
         }}
     }
 
     sub poweroff_system() {
         ; use the SMC to shutdown the computer
-        void cx16.i2c_write_byte($42, $01, $00)
+        ; in a loop for the event where the shutdown command does not in fact immediately shutdown the system
+        repeat {
+            void cx16.i2c_write_byte($42, $01, $00)
+        }
     }
 
     asmsub wait(uword jiffies @AY) clobbers(X) {
diff --git a/docs/source/todo.rst b/docs/source/todo.rst
index 0f1084904..8a3b7c746 100644
--- a/docs/source/todo.rst
+++ b/docs/source/todo.rst
@@ -37,7 +37,6 @@ Future Things and Ideas
 
 IR/VM
 -----
-- can onetimeInitializationNumericValue be removed from IRStStaticVariable?
 - getting it in shape for code generation...: the IR file should be able to encode every detail about a prog8 program (the VM doesn't have to actually be able to run all of it though!)
 - fix call() return value handling
 - proper code gen for the CALLI instruction and that it (optionally) returns a word value that needs to be assigned to a reg
diff --git a/examples/test.p8 b/examples/test.p8
index a449030de..32fee936d 100644
--- a/examples/test.p8
+++ b/examples/test.p8
@@ -3,16 +3,10 @@
 %option no_sysinit, romable
 
 main {
-    ubyte[100] @shared array1
-    ubyte[100] @shared array2 = [42] *100
-
     sub start() {
-        uword @shared pointer = $4000
-        ubyte @shared size = 42
-
-        for cx16.r0L in 5 to size {
-            @(pointer)++
-            @(pointer)--
+        repeat {
+            if cbm.GETIN2()==27
+                sys.poweroff_system()
         }
     }
 }