From 747a528c2721004f1f87352f1fbb94cb61db2c42 Mon Sep 17 00:00:00 2001
From: Franco Colmenarez <info@francoacg.com>
Date: Thu, 11 Nov 2021 10:29:00 -0500
Subject: [PATCH] Little tweak to timer

---
 src/render.rs |  2 ++
 src/timer.rs  | 10 ++++++++--
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/render.rs b/src/render.rs
index 1067bb4..d945b3d 100644
--- a/src/render.rs
+++ b/src/render.rs
@@ -39,6 +39,8 @@ pub fn start_eventloop() {
     let mut emulator = Emulator::new();
 
     event_loop.run(move |event, _, control_flow| {
+        *control_flow = ControlFlow::Wait;
+
         // Handle input events
         if input.update(&event) {
             // Close events
diff --git a/src/timer.rs b/src/timer.rs
index 8502807..0068221 100644
--- a/src/timer.rs
+++ b/src/timer.rs
@@ -13,6 +13,8 @@ pub const TIMER_CONTROL_ADDRESS: u16          = 0xFF07;
 pub struct Timer {
     divider: u16,
     prev_result: bool,
+    is_enabled: bool,
+    control: u8,
 }
 
 impl Timer {
@@ -20,7 +22,9 @@ impl Timer {
     pub fn new() -> Self {
         Self {
             divider: 0,
+            control: 0,
             prev_result: false,
+            is_enabled: false,
         }
     }
 
@@ -30,6 +34,8 @@ impl Timer {
     }
     
     pub fn do_cycles(&mut self, bus: &mut Bus, cycles: Cycles) {
+        self.is_enabled = Timer::is_timer_enabled(bus);
+        self.control = bus.read(TIMER_CONTROL_ADDRESS);
         let mut count = 0;
         while count < cycles.0 {
             self.cycle(bus);
@@ -41,7 +47,7 @@ impl Timer {
     fn cycle(&mut self, bus: &mut Bus) {
         self.divider = self.divider.wrapping_add(1);
 
-        let result = Timer::is_timer_enabled(bus) && self.get_tima_rate(bus);
+        let result = self.is_enabled && self.get_tima_rate(bus);
 
         if self.prev_result && !result {
             let tima = bus.read(TIMER_COUNTER_ADDRESS).wrapping_add(1);
@@ -61,7 +67,7 @@ impl Timer {
     }
 
     fn get_tima_rate(&self, bus: &Bus) -> bool {
-        let clock_select = bus.read(TIMER_CONTROL_ADDRESS) & 0b0000_0011;
+        let clock_select = self.control & 0b0000_0011;
         match clock_select {
             0b00 => ((self.divider >> 9) & 1) == 1,
             0b01 => ((self.divider >> 3) & 1) == 1,