From 9232e55563c0dd7394d6691725a6fad8d4bd85b1 Mon Sep 17 00:00:00 2001
From: Alex Voinea <voinea.dragos.alexandru@gmail.com>
Date: Wed, 4 Aug 2021 11:06:00 +0300
Subject: [PATCH] millis interrupt

---
 src/hal/CMakeLists.txt   |  1 +
 src/hal/avr/timers.cpp   | 17 +++++++++++++++++
 src/hal/timers.h         | 26 +++++++++++++++++++++++---
 src/main.cpp             |  4 ++++
 src/modules/timebase.cpp | 11 +++++++++++
 src/modules/timebase.h   |  3 ++-
 6 files changed, 58 insertions(+), 4 deletions(-)
 create mode 100644 src/hal/avr/timers.cpp

diff --git a/src/hal/CMakeLists.txt b/src/hal/CMakeLists.txt
index 169c0a8..04c4602 100644
--- a/src/hal/CMakeLists.txt
+++ b/src/hal/CMakeLists.txt
@@ -4,6 +4,7 @@ target_sources(
           avr/usart.cpp
           avr/shr16.cpp
           avr/eeprom.cpp
+          avr/timers.cpp
           avr/tmc2130.cpp
           adc.cpp
           avr/spi.cpp
diff --git a/src/hal/avr/timers.cpp b/src/hal/avr/timers.cpp
new file mode 100644
index 0000000..495e217
--- /dev/null
+++ b/src/hal/avr/timers.cpp
@@ -0,0 +1,17 @@
+#include "../timers.h"
+
+namespace hal {
+namespace timers {
+
+void Configure_CTC8(const uint8_t timer, Tim8bit_TypeDef *const htim8, Tim8bit_CTC_config *const conf) {
+    TIMSK[timer] = 0; //clear all interrupt sources
+    htim8->TCCRxA = (1 << 1); //WGM=2 (CTC)
+    htim8->TCCRxB = conf->cs; //CS = bits from conf (<<0)
+    htim8->OCRxA = conf->ocra; //set the TOP value from config
+    htim8->TCNTx = 0; //initialize timer to 0
+    TIFR[timer] = 0xFF; //clear all interrupt flags
+    TIMSK[timer] = (1 << 1); //enable OCIExA
+}
+
+}
+}
diff --git a/src/hal/timers.h b/src/hal/timers.h
index 6a39a55..b9ebe5b 100644
--- a/src/hal/timers.h
+++ b/src/hal/timers.h
@@ -1,13 +1,33 @@
 #pragma once
+#include <avr/io.h>
 
+#define TIMER0 ((hal::timers::Tim8bit_TypeDef *)&TCCR0A)
 namespace hal {
 
 /// Hardware Abstraction Layer for the CPU's internal timers
 namespace timers {
 
-void ConfigureTimer(uint8_t timer /* some config struct */);
-void StartTimer(uint8_t timer);
-void StopTimer(uint8_t timer);
+// void ConfigureTimer(uint8_t timer /* some config struct */);
+// void StartTimer(uint8_t timer);
+// void StopTimer(uint8_t timer);
+
+struct Tim8bit_TypeDef {
+    volatile uint8_t TCCRxA;
+    volatile uint8_t TCCRxB;
+    volatile uint8_t TCNTx;
+    volatile uint8_t OCRxA;
+    volatile uint8_t OCRxB;
+};
+
+constexpr volatile uint8_t *TIFR = &TIFR0;
+constexpr volatile uint8_t *TIMSK = &TIMSK0;
+
+struct Tim8bit_CTC_config {
+    uint8_t cs : 3; ///clock source as per datasheet. It is not consistent between timer types
+    uint8_t ocra; ///compare value for TOP
+};
+
+void Configure_CTC8(const uint8_t timer, Tim8bit_TypeDef *const htim8, Tim8bit_CTC_config *const conf);
 
 } // namespace cpu
 } // namespace hal
diff --git a/src/main.cpp b/src/main.cpp
index aa8e2eb..c233c7b 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -18,6 +18,7 @@
 #include "modules/protocol.h"
 #include "modules/selector.h"
 #include "modules/user_input.h"
+#include "modules/timebase.h"
 
 #include "logic/command_base.h"
 #include "logic/cut_filament.h"
@@ -38,6 +39,7 @@ namespace ml = modules::leds;
 namespace ms = modules::selector;
 namespace mg = modules::globals;
 namespace mu = modules::user_input;
+namespace mt = modules::time;
 
 namespace hu = hal::usart;
 
@@ -101,6 +103,8 @@ void setup() {
 
     cpu::Init();
 
+    mt::timebase.Init();
+
     mg::globals.Init();
 
     // watchdog init
diff --git a/src/modules/timebase.cpp b/src/modules/timebase.cpp
index 3db6852..edf2a27 100644
--- a/src/modules/timebase.cpp
+++ b/src/modules/timebase.cpp
@@ -1,5 +1,6 @@
 #include "timebase.h"
 #include "../hal/timers.h"
+#include <avr/interrupt.h>
 
 namespace modules {
 namespace time {
@@ -7,9 +8,15 @@ namespace time {
 Timebase timebase;
 
 void Timebase::Init() {
+    hal::timers::Tim8bit_CTC_config tim8ctc_conf = {
+        .cs = 3, // ck/64
+        .ocra = 250 - 1,
+    };
+    hal::timers::Configure_CTC8(0, TIMER0, &tim8ctc_conf);
 }
 
 void Timebase::Isr() {
+    ms++;
 }
 
 uint16_t Timebase::Millis() const {
@@ -18,3 +25,7 @@ uint16_t Timebase::Millis() const {
 
 } // namespace time
 } // namespace modules
+
+ISR(TIMER0_COMPA_vect) {
+    modules::time::timebase.Isr();
+}
diff --git a/src/modules/timebase.h b/src/modules/timebase.h
index 0241e42..61b6790 100644
--- a/src/modules/timebase.h
+++ b/src/modules/timebase.h
@@ -21,9 +21,10 @@ public:
     ///  (usually the start of the firmware)
     uint16_t Millis() const;
 
+    void Isr();
+
 private:
     uint16_t ms;
-    static void Isr();
 };
 
 /// The one and only instance of Selector in the FW