From 0116e1c7fc1cfe469f24b1c3aa8b964f8b768455 Mon Sep 17 00:00:00 2001
From: Simon Doppler <dopsi@dopsi.ch>
Date: Mon, 19 Aug 2019 11:16:43 +0200
Subject: [PATCH 01/10] return true if the output value was changed

See #3
---
 src/circuit.rs                              | 6 ++----
 src/lib.rs                                  | 2 +-
 src/models/gates/mod.rs                     | 8 ++++++--
 src/models/gates/mux.rs                     | 6 +++++-
 src/models/gates/tri.rs                     | 5 ++++-
 src/models/rtlib/arithmic/add.rs            | 5 ++++-
 src/models/rtlib/arithmic/twoscomplement.rs | 4 +++-
 src/models/rtlib/memory/rom.rs              | 5 ++++-
 src/port/mod.rs                             | 2 +-
 src/signal.rs                               | 6 +++++-
 10 files changed, 35 insertions(+), 14 deletions(-)

diff --git a/src/circuit.rs b/src/circuit.rs
index 115c50f..32d3446 100644
--- a/src/circuit.rs
+++ b/src/circuit.rs
@@ -6,10 +6,8 @@ pub struct Circuit {
 }
 
 impl Circuit {
-    pub fn tick(&mut self) {
-        for u in &mut self.updater {
-            u.update();
-        }
+    pub fn tick(&mut self) -> bool {
+        self.updater.iter_mut().fold(false, |acc, u| acc | u.update())
     }
 
     pub fn add_updater<T: Updateable + Clone + 'static>(&mut self, updater: &T) {
diff --git a/src/lib.rs b/src/lib.rs
index 22d3fe2..8ed5183 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -106,5 +106,5 @@ pub trait Updateable {
     /// When this trait function is called you should perform any action necessary to update the
     /// struct, e.g. reading input values and updating output values. These changes should be
     /// instant.
-    fn update(&mut self);
+    fn update(&mut self) -> bool;
 }
diff --git a/src/models/gates/mod.rs b/src/models/gates/mod.rs
index f81f9b1..288d86b 100644
--- a/src/models/gates/mod.rs
+++ b/src/models/gates/mod.rs
@@ -25,8 +25,10 @@ macro_rules! create_simple_1i1o_gate {
         }
 
         impl Updateable for $name {
-            fn update(&mut self) {
+            fn update(&mut self) -> bool {
+                let old_value = self.z.inner.value.read().unwrap().clone();
                 self.z.replace($func(self.a.value()));
+                old_value != *self.z.inner.value.read().unwrap()
             }
         }
 
@@ -57,8 +59,10 @@ macro_rules! create_simple_2i1o_gate {
         }
 
         impl Updateable for $name {
-            fn update(&mut self) {
+            fn update(&mut self) -> bool {
+                let old_value = self.z.inner.value.read().unwrap().clone();
                 self.z.replace($func(self.a.value(), self.b.value()));
+                old_value != *self.z.inner.value.read().unwrap()
             }
         }
 
diff --git a/src/models/gates/mux.rs b/src/models/gates/mux.rs
index df35f08..20a1290 100644
--- a/src/models/gates/mux.rs
+++ b/src/models/gates/mux.rs
@@ -67,7 +67,9 @@ pub struct Mux {
 }
 
 impl Updateable for Mux {
-    fn update(&mut self) {
+    fn update(&mut self) -> bool {
+        //let old_value = self.z.inner;
+        let old_value = self.z.inner.value.read().unwrap().clone();
         self.z.replace(if self.s.value().is_1H() {
             self.b.value()
         } else if self.s.value().is_0L() {
@@ -75,6 +77,8 @@ impl Updateable for Mux {
         } else {
             Ieee1164::_X
         });
+
+        old_value != *self.z.inner.value.read().unwrap()
     }
 }
 
diff --git a/src/models/gates/tri.rs b/src/models/gates/tri.rs
index db5e084..15dd446 100644
--- a/src/models/gates/tri.rs
+++ b/src/models/gates/tri.rs
@@ -19,7 +19,8 @@ pub struct TriBuffer {
 }
 
 impl Updateable for TriBuffer {
-    fn update(&mut self) {
+    fn update(&mut self) -> bool {
+        let old_value = self.z.inner.value.read().unwrap().clone();
         self.z.replace(if self.s.value().is_1H() {
             self.a.value()
         } else if self.s.value().is_0L() {
@@ -27,6 +28,8 @@ impl Updateable for TriBuffer {
         } else {
             Ieee1164::_X
         });
+
+        old_value != *self.z.inner.value.read().unwrap()
     }
 }
 
diff --git a/src/models/rtlib/arithmic/add.rs b/src/models/rtlib/arithmic/add.rs
index 6c85a18..f294120 100644
--- a/src/models/rtlib/arithmic/add.rs
+++ b/src/models/rtlib/arithmic/add.rs
@@ -17,7 +17,8 @@ pub struct Add {
 }
 
 impl Updateable for Add {
-    fn update(&mut self) {
+    fn update(&mut self) -> bool {
+        let old_value = self.s.inner.value.read().unwrap().clone();
         let a = self.a.value();
         let b = self.b.value();
         self.s.with_value_mut(|v| match (a.as_u128(), b.as_u128()) {
@@ -26,5 +27,7 @@ impl Updateable for Add {
                 .unwrap(),
             _ => v.set_all_to(Ieee1164::_U),
         });
+
+        old_value != *self.s.inner.value.read().unwrap()
     }
 }
diff --git a/src/models/rtlib/arithmic/twoscomplement.rs b/src/models/rtlib/arithmic/twoscomplement.rs
index dcded09..0cde0a4 100644
--- a/src/models/rtlib/arithmic/twoscomplement.rs
+++ b/src/models/rtlib/arithmic/twoscomplement.rs
@@ -11,8 +11,10 @@ pub struct TwosComplement {
 }
 
 impl Updateable for TwosComplement {
-    fn update(&mut self) {
+    fn update(&mut self) -> bool {
+        let old_value = self.y.inner.value.read().unwrap().clone();
         let a = self.a.value();
         self.y.with_value_mut(|y| *y = (!a).incr());
+        old_value != *self.y.inner.value.read().unwrap()
     }
 }
diff --git a/src/models/rtlib/memory/rom.rs b/src/models/rtlib/memory/rom.rs
index 385ffd9..f291115 100644
--- a/src/models/rtlib/memory/rom.rs
+++ b/src/models/rtlib/memory/rom.rs
@@ -82,8 +82,9 @@ impl fmt::Debug for Rom1kx8 {
 }
 
 impl Updateable for Rom1kx8 {
-    fn update(&mut self) {
+    fn update(&mut self) -> bool {
         println!("ROM Update");
+        let old_value = self.data.inner.value.read().unwrap().clone();
         let ncs = self.n_chip_select.value();
         let noe = self.n_output_enable.value();
         let data = if let Some(addr) = self.addr.value().as_u128() {
@@ -105,6 +106,8 @@ impl Updateable for Rom1kx8 {
                 f.set_all_to(Ieee1164::_X);
             }
         });
+
+        old_value != *self.data.inner.value.read().unwrap()
     }
 }
 
diff --git a/src/port/mod.rs b/src/port/mod.rs
index da59788..b2c8b37 100644
--- a/src/port/mod.rs
+++ b/src/port/mod.rs
@@ -13,6 +13,6 @@ pub use self::pport::Port;
 
 #[derive(Debug)]
 pub(crate) struct InnerPort<T> {
-    value: RwLock<T>,
+    pub value: RwLock<T>,
     signal: WeakSignal<T>,
 }
diff --git a/src/signal.rs b/src/signal.rs
index c8775f1..4683e23 100644
--- a/src/signal.rs
+++ b/src/signal.rs
@@ -200,9 +200,11 @@ where
     for<'a> &'a T: Resolve<&'a T, Output = T>,
     T: Clone + std::fmt::Debug,
 {
-    fn update(&mut self) {
+    fn update(&mut self) -> bool {
         self.remove_expired_portconnector();
 
+        let old_value = self.inner.output_ports.read().unwrap().clone();
+
         let in_guard = self.inner.input_ports.write().unwrap();
         let mut iter = in_guard.iter();
 
@@ -229,6 +231,8 @@ where
                 .iter_mut()
                 .for_each(|p| p.set_value(r.clone()));
         }
+
+        old_value != *self.inner.output_ports.read().unwrap()
     }
 }
 

From 1e5e68bdd495053d07ff0a7fb88e46667dbb045e Mon Sep 17 00:00:00 2001
From: Simon Doppler <dopsi@dopsi.ch>
Date: Mon, 19 Aug 2019 11:19:54 +0200
Subject: [PATCH 02/10] document changes (return true if value changed)

---
 src/lib.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/lib.rs b/src/lib.rs
index 8ed5183..26bf393 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -106,5 +106,7 @@ pub trait Updateable {
     /// When this trait function is called you should perform any action necessary to update the
     /// struct, e.g. reading input values and updating output values. These changes should be
     /// instant.
+    ///
+    /// Returns `true` if the output value of the updatable object was changed.
     fn update(&mut self) -> bool;
 }

From 5bc1634e2d417c10b3e9343ac4f8b3185d9a53c6 Mon Sep 17 00:00:00 2001
From: Simon Doppler <dopsi@dopsi.ch>
Date: Mon, 19 Aug 2019 13:13:55 +0200
Subject: [PATCH 03/10] reuse old values from replace

---
 src/models/gates/mod.rs | 6 ++----
 src/models/gates/mux.rs | 4 +---
 src/models/gates/tri.rs | 3 +--
 3 files changed, 4 insertions(+), 9 deletions(-)

diff --git a/src/models/gates/mod.rs b/src/models/gates/mod.rs
index 288d86b..9a7ab11 100644
--- a/src/models/gates/mod.rs
+++ b/src/models/gates/mod.rs
@@ -26,8 +26,7 @@ macro_rules! create_simple_1i1o_gate {
 
         impl Updateable for $name {
             fn update(&mut self) -> bool {
-                let old_value = self.z.inner.value.read().unwrap().clone();
-                self.z.replace($func(self.a.value()));
+                let old_value = self.z.replace($func(self.a.value()));
                 old_value != *self.z.inner.value.read().unwrap()
             }
         }
@@ -60,8 +59,7 @@ macro_rules! create_simple_2i1o_gate {
 
         impl Updateable for $name {
             fn update(&mut self) -> bool {
-                let old_value = self.z.inner.value.read().unwrap().clone();
-                self.z.replace($func(self.a.value(), self.b.value()));
+                let old_value = self.z.replace($func(self.a.value(), self.b.value()));
                 old_value != *self.z.inner.value.read().unwrap()
             }
         }
diff --git a/src/models/gates/mux.rs b/src/models/gates/mux.rs
index 20a1290..929d9f8 100644
--- a/src/models/gates/mux.rs
+++ b/src/models/gates/mux.rs
@@ -68,9 +68,7 @@ pub struct Mux {
 
 impl Updateable for Mux {
     fn update(&mut self) -> bool {
-        //let old_value = self.z.inner;
-        let old_value = self.z.inner.value.read().unwrap().clone();
-        self.z.replace(if self.s.value().is_1H() {
+        let old_value = self.z.replace(if self.s.value().is_1H() {
             self.b.value()
         } else if self.s.value().is_0L() {
             self.a.value()
diff --git a/src/models/gates/tri.rs b/src/models/gates/tri.rs
index 15dd446..408e9c2 100644
--- a/src/models/gates/tri.rs
+++ b/src/models/gates/tri.rs
@@ -20,8 +20,7 @@ pub struct TriBuffer {
 
 impl Updateable for TriBuffer {
     fn update(&mut self) -> bool {
-        let old_value = self.z.inner.value.read().unwrap().clone();
-        self.z.replace(if self.s.value().is_1H() {
+        let old_value =  self.z.replace(if self.s.value().is_1H() {
             self.a.value()
         } else if self.s.value().is_0L() {
             Ieee1164::_Z

From 7abd8b576ea7385162c90b74209a5c4ea9ebe3e1 Mon Sep 17 00:00:00 2001
From: Simon Doppler <dopsi@dopsi.ch>
Date: Mon, 19 Aug 2019 12:47:50 +0200
Subject: [PATCH 04/10] document circuit

---
 src/circuit.rs | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/src/circuit.rs b/src/circuit.rs
index 32d3446..b70c017 100644
--- a/src/circuit.rs
+++ b/src/circuit.rs
@@ -1,15 +1,47 @@
 use crate::Updateable;
 
+/// A `Circuit` is a combination of connected logic elements
+///
+/// A `Circuit` holds references of [`Updateable`](Updateable) structs
+/// ([`Port`](crate::port::Port), ...), which are updated on every call of
+/// tick.
 #[derive(Default)]
 pub struct Circuit {
     updater: Vec<Box<dyn Updateable>>,
 }
 
 impl Circuit {
+    /// The clock tick function
+    /// This function propagates the logic values by one Updateable element.
+    ///
+    /// Returns `true` as long as at least one element's output value has changed in the circuit.
+    ///
+    /// ```
+    /// let mut circuit = Circuit::default();
+    /// /* Configure updaters */
+    ///
+    /// let mut clock_cycles = 0_u32;
+    /// while circuit.tick() && clock_cycles < 100 { // 100 is a arbitrary value, to avoid looping if we have an oscillating circuit
+    ///     clock_cycles += 1;
+    /// }
+    /// ```
     pub fn tick(&mut self) -> bool {
         self.updater.iter_mut().fold(false, |acc, u| acc | u.update())
     }
 
+    /// Add an [`Updateable`](Updateable) to the `Circuit`
+    ///
+    /// ```
+    /// let mut sig = Signal::default();
+    /// // Configure signal here
+    ///
+    /// let or = OrGate::default(); // Gates do not need to be mutable
+    /// // Connect gate here
+    ///
+    /// let mut circuit = Circuit::default();
+    /// circuit.add_updater(&sig);
+    /// circuit.add_updater(&or);
+    /// ```
     pub fn add_updater<T: Updateable + Clone + 'static>(&mut self, updater: &T) {
         self.updater.push(Box::new(updater.clone()))
     }

From f94cdf9cc06605aa0d917e7111a39432a80c3b16 Mon Sep 17 00:00:00 2001
From: Simon Doppler <dopsi@dopsi.ch>
Date: Mon, 19 Aug 2019 13:39:10 +0200
Subject: [PATCH 05/10] Circuit::tick() is not a clock tick

---
 src/circuit.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/circuit.rs b/src/circuit.rs
index b70c017..510d66f 100644
--- a/src/circuit.rs
+++ b/src/circuit.rs
@@ -11,7 +11,7 @@ pub struct Circuit {
 }
 
 impl Circuit {
-    /// The clock tick function
+    /// The update tick function
     /// This function propagates the logic values by one Updateable element.
     ///
     /// Returns `true` as long as at least one element's output value has changed in the circuit.

From c37724593052f04355962fdfd677ff0a454c5cb9 Mon Sep 17 00:00:00 2001
From: Simon Doppler <dopsi@dopsi.ch>
Date: Mon, 19 Aug 2019 13:39:42 +0200
Subject: [PATCH 06/10] update fulladder example to use the tick return value

---
 examples/fulladder.rs | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/examples/fulladder.rs b/examples/fulladder.rs
index b89e775..51ea16e 100644
--- a/examples/fulladder.rs
+++ b/examples/fulladder.rs
@@ -110,17 +110,29 @@ fn main() {
         y.replace(triple[1]);
         c.replace(triple[2]);
 
-        for _ in 0..3 {
-            circuit.tick();
+        let mut cycle_count = 0_u32;
+        while circuit.tick() && cycle_count < 10_u32 {
+            cycle_count += 1;
         }
 
+        // If the number of required ticks is known, it is possible to use
+        // a loop with a fixed number of iterations
+        // ```
+        // for _ in 0..3 {
+        //     circuit.tick();
+        // }
+        // ```
+
+        cycle_count += 1; // To get the correct number of cycles
+
         println!(
-            "{} + {} + {} = {}{}",
+            "{} + {} + {} = {}{} (used {} cycles to reach a stable circuit)",
             triple[0],
             triple[1],
             triple[2],
             cout.value(),
-            s.value()
+            s.value(),
+            cycle_count
         );
         assert_eq!(triple[3], s.value());
         assert_eq!(triple[4], cout.value());

From 40ae49c442b3c363644fdfdea1468aa8a1df9240 Mon Sep 17 00:00:00 2001
From: Simon Doppler <dopsi@dopsi.ch>
Date: Mon, 19 Aug 2019 14:01:33 +0200
Subject: [PATCH 07/10] add missing imports

---
 src/circuit.rs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/circuit.rs b/src/circuit.rs
index 510d66f..1b983b0 100644
--- a/src/circuit.rs
+++ b/src/circuit.rs
@@ -17,6 +17,9 @@ impl Circuit {
     /// Returns `true` as long as at least one element's output value has changed in the circuit.
     ///
     /// ```
+    /// use logical::{Circuit, Signal};
+    /// use logical::models::gates::OrGate;
+    ///
     /// let mut circuit = Circuit::default();
     /// /* Configure updaters */
     ///
@@ -32,7 +35,10 @@ impl Circuit {
     /// Add an [`Updateable`](Updateable) to the `Circuit`
     ///
     /// ```
-    /// let mut sig = Signal::default();
+    /// use logical::{Circuit, Signal, Ieee1164};
+    /// use logical::models::gates::OrGate;
+    ///
+    /// let mut sig: logical::Signal<Ieee1164> = Signal::default();
     /// // Configure signal here
     ///
     /// let or = OrGate::default(); // Gates do not need to be mutable

From 9b5e9aadedd2dabe34e038aa99e057c9c22d93eb Mon Sep 17 00:00:00 2001
From: Simon Doppler <dopsi@dopsi.ch>
Date: Mon, 19 Aug 2019 16:45:14 +0200
Subject: [PATCH 08/10] use PortConnector instead of exposing inner port

---
 src/models/gates/mod.rs                     | 10 ++++++----
 src/models/gates/mux.rs                     |  8 +++++---
 src/models/gates/tri.rs                     |  7 ++++---
 src/models/rtlib/arithmic/add.rs            |  5 +++--
 src/models/rtlib/arithmic/twoscomplement.rs |  6 ++++--
 src/models/rtlib/memory/rom.rs              |  5 +++--
 src/port/mod.rs                             |  2 +-
 7 files changed, 26 insertions(+), 17 deletions(-)

diff --git a/src/models/gates/mod.rs b/src/models/gates/mod.rs
index 9a7ab11..85b69cf 100644
--- a/src/models/gates/mod.rs
+++ b/src/models/gates/mod.rs
@@ -26,8 +26,9 @@ macro_rules! create_simple_1i1o_gate {
 
         impl Updateable for $name {
             fn update(&mut self) -> bool {
-                let old_value = self.z.replace($func(self.a.value()));
-                old_value != *self.z.inner.value.read().unwrap()
+                let new_value = $func(self.a.value());
+                let old_value = self.z.replace(new_value);
+                old_value != new_value
             }
         }
 
@@ -59,8 +60,9 @@ macro_rules! create_simple_2i1o_gate {
 
         impl Updateable for $name {
             fn update(&mut self) -> bool {
-                let old_value = self.z.replace($func(self.a.value(), self.b.value()));
-                old_value != *self.z.inner.value.read().unwrap()
+                let new_value = $func(self.a.value(), self.b.value());
+                let old_value = self.z.replace(new_value);
+                old_value != new_value
             }
         }
 
diff --git a/src/models/gates/mux.rs b/src/models/gates/mux.rs
index 929d9f8..ef76e0a 100644
--- a/src/models/gates/mux.rs
+++ b/src/models/gates/mux.rs
@@ -68,15 +68,17 @@ pub struct Mux {
 
 impl Updateable for Mux {
     fn update(&mut self) -> bool {
-        let old_value = self.z.replace(if self.s.value().is_1H() {
+        let new_value = if self.s.value().is_1H() {
             self.b.value()
         } else if self.s.value().is_0L() {
             self.a.value()
         } else {
             Ieee1164::_X
-        });
+        };
 
-        old_value != *self.z.inner.value.read().unwrap()
+        let old_value = self.z.replace(new_value);
+
+        old_value != new_value
     }
 }
 
diff --git a/src/models/gates/tri.rs b/src/models/gates/tri.rs
index 408e9c2..165873e 100644
--- a/src/models/gates/tri.rs
+++ b/src/models/gates/tri.rs
@@ -20,15 +20,16 @@ pub struct TriBuffer {
 
 impl Updateable for TriBuffer {
     fn update(&mut self) -> bool {
-        let old_value =  self.z.replace(if self.s.value().is_1H() {
+        let new_value = if self.s.value().is_1H() {
             self.a.value()
         } else if self.s.value().is_0L() {
             Ieee1164::_Z
         } else {
             Ieee1164::_X
-        });
+        };
+        let old_value =  self.z.replace(new_value);
 
-        old_value != *self.z.inner.value.read().unwrap()
+        old_value != new_value
     }
 }
 
diff --git a/src/models/rtlib/arithmic/add.rs b/src/models/rtlib/arithmic/add.rs
index f294120..b2da060 100644
--- a/src/models/rtlib/arithmic/add.rs
+++ b/src/models/rtlib/arithmic/add.rs
@@ -1,6 +1,7 @@
 use crate::direction::{Input, Output};
 use crate::logicbit::mask_from_width;
 use crate::{Ieee1164, LogicVector, Port, Updateable};
+use crate::port::PortConnector;
 
 /// This models an actual adder that will add up both inputs.
 ///
@@ -18,7 +19,7 @@ pub struct Add {
 
 impl Updateable for Add {
     fn update(&mut self) -> bool {
-        let old_value = self.s.inner.value.read().unwrap().clone();
+        let old_value = PortConnector::from(self.s.clone()).value();
         let a = self.a.value();
         let b = self.b.value();
         self.s.with_value_mut(|v| match (a.as_u128(), b.as_u128()) {
@@ -28,6 +29,6 @@ impl Updateable for Add {
             _ => v.set_all_to(Ieee1164::_U),
         });
 
-        old_value != *self.s.inner.value.read().unwrap()
+        old_value != PortConnector::from(self.s.clone()).value()
     }
 }
diff --git a/src/models/rtlib/arithmic/twoscomplement.rs b/src/models/rtlib/arithmic/twoscomplement.rs
index 0cde0a4..7ca51c4 100644
--- a/src/models/rtlib/arithmic/twoscomplement.rs
+++ b/src/models/rtlib/arithmic/twoscomplement.rs
@@ -1,6 +1,8 @@
 use crate::direction::{Input, Output};
 use crate::{LogicVector, Port, Updateable};
 
+use crate::port::PortConnector;
+
 /// Computes the two's complement of the applied value.
 #[derive(Debug)]
 pub struct TwosComplement {
@@ -12,9 +14,9 @@ pub struct TwosComplement {
 
 impl Updateable for TwosComplement {
     fn update(&mut self) -> bool {
-        let old_value = self.y.inner.value.read().unwrap().clone();
+        let old_value = PortConnector::from(self.y.clone()).value();
         let a = self.a.value();
         self.y.with_value_mut(|y| *y = (!a).incr());
-        old_value != *self.y.inner.value.read().unwrap()
+        old_value != PortConnector::from(self.y.clone()).value()
     }
 }
diff --git a/src/models/rtlib/memory/rom.rs b/src/models/rtlib/memory/rom.rs
index f291115..5c4d220 100644
--- a/src/models/rtlib/memory/rom.rs
+++ b/src/models/rtlib/memory/rom.rs
@@ -3,6 +3,7 @@ use std::iter::FromIterator;
 
 use crate::direction::{Input, Output};
 use crate::{Ieee1164, LogicVector, Port, Updateable};
+use crate::port::PortConnector;
 
 /// This struct represents a Read-only-memory with a size of 1kB (1024 bytes).
 ///
@@ -84,7 +85,7 @@ impl fmt::Debug for Rom1kx8 {
 impl Updateable for Rom1kx8 {
     fn update(&mut self) -> bool {
         println!("ROM Update");
-        let old_value = self.data.inner.value.read().unwrap().clone();
+        let old_value = PortConnector::from(self.data.clone()).value();
         let ncs = self.n_chip_select.value();
         let noe = self.n_output_enable.value();
         let data = if let Some(addr) = self.addr.value().as_u128() {
@@ -107,7 +108,7 @@ impl Updateable for Rom1kx8 {
             }
         });
 
-        old_value != *self.data.inner.value.read().unwrap()
+        old_value != PortConnector::from(self.data.clone()).value()
     }
 }
 
diff --git a/src/port/mod.rs b/src/port/mod.rs
index b2c8b37..da59788 100644
--- a/src/port/mod.rs
+++ b/src/port/mod.rs
@@ -13,6 +13,6 @@ pub use self::pport::Port;
 
 #[derive(Debug)]
 pub(crate) struct InnerPort<T> {
-    pub value: RwLock<T>,
+    value: RwLock<T>,
     signal: WeakSignal<T>,
 }

From 64432d175bc739f94cf53a6b27722adf39982141 Mon Sep 17 00:00:00 2001
From: Simon Doppler <dopsi@dopsi.ch>
Date: Mon, 19 Aug 2019 16:45:38 +0200
Subject: [PATCH 09/10] clear up example

---
 examples/fulladder.rs | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/examples/fulladder.rs b/examples/fulladder.rs
index 51ea16e..c31b741 100644
--- a/examples/fulladder.rs
+++ b/examples/fulladder.rs
@@ -110,8 +110,8 @@ fn main() {
         y.replace(triple[1]);
         c.replace(triple[2]);
 
-        let mut cycle_count = 0_u32;
-        while circuit.tick() && cycle_count < 10_u32 {
+        let mut cycle_count = 1;
+        while circuit.tick() && cycle_count < 11 {
             cycle_count += 1;
         }
 
@@ -123,8 +123,6 @@ fn main() {
         // }
         // ```
 
-        cycle_count += 1; // To get the correct number of cycles
-
         println!(
             "{} + {} + {} = {}{} (used {} cycles to reach a stable circuit)",
             triple[0],

From 803c1f297efd59060dc93e1c76af7777fa66db0e Mon Sep 17 00:00:00 2001
From: Simon Doppler <dopsi@dopsi.ch>
Date: Mon, 19 Aug 2019 16:49:03 +0200
Subject: [PATCH 10/10] remove suffix in documentation

---
 src/circuit.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/circuit.rs b/src/circuit.rs
index 1b983b0..d99dbc0 100644
--- a/src/circuit.rs
+++ b/src/circuit.rs
@@ -23,7 +23,7 @@ impl Circuit {
     /// let mut circuit = Circuit::default();
     /// /* Configure updaters */
     ///
-    /// let mut clock_cycles = 0_u32;
+    /// let mut clock_cycles = 0;
     /// while circuit.tick() && clock_cycles < 100 { // 100 is a arbitrary value, to avoid looping if we have an oscillating circuit
     ///     clock_cycles += 1;
     /// }