From ec338fb9300b9aa321b706b457ecaed93cbfb288 Mon Sep 17 00:00:00 2001
From: tkl <tkl@blackfinn.de>
Date: Thu, 26 Dec 2019 10:15:25 +0100
Subject: [PATCH] wip

---
 Makefile   |  13 +++--
 src/main.c | 138 +++++++++++++++++++++++++++++++++++++++++------------
 2 files changed, 113 insertions(+), 38 deletions(-)

diff --git a/Makefile b/Makefile
index dcfc7c3..cc74de3 100644
--- a/Makefile
+++ b/Makefile
@@ -3,16 +3,15 @@ CROSS_COMPILE ?= avr-
 TARGET_FILE ?= avr.elf
 
 MCU = attiny85
-# MCU = atmega8
 
-# C_FLAGS += -Wall -Werror
+C_FLAGS += -Wall -Werror
 C_FLAGS += -Os
 C_FLAGS += -mmcu=$(MCU)
-# C_FLAGS += -ffunction-sections
-# C_FLAGS += -fdata-sections
-# C_FLAGS += -std=c11
-# C_FLAGS += -pedantic
-# C_FLAGS += -pedantic-errors
+C_FLAGS += -ffunction-sections
+C_FLAGS += -fdata-sections
+C_FLAGS += -std=c11
+C_FLAGS += -pedantic
+C_FLAGS += -pedantic-errors
 C_FLAGS += -Iinclude
 
 LD_FLAGS += -mmcu=$(MCU)
diff --git a/src/main.c b/src/main.c
index 9e305d9..deee5fd 100644
--- a/src/main.c
+++ b/src/main.c
@@ -15,25 +15,39 @@
 #define POWER_PIN       3
 #define IGNITION_PIN    4
 
-#define SHUTDOWN_TIME_MS 5000UL
+#define SHUTDOWN_TIME_MS 1000UL * 60
+#define GUARD_TIME_MS 1000UL * 5
 
 #define ignition_on() (PINB & (1 << IGNITION_PIN))
 #define power_on() (PINB & (1 << POWER_PIN))
 
-bool is_shutdown;
-volatile uint32_t tick;
-
 enum power {
     off = 0,
     on
 };
 
+enum state {
+    state_init = 0,
+    state_on,
+    state_shutdown,
+    state_guard,
+    state_off
+};
+
+volatile uint32_t tick;
+uint32_t shutdown_expire, guard_expire;
+
+enum state current_state;
+
 void setup_gpio()
 {
     DDRB = 0xff;
     PORTB = 0;
     DDRB &= ~(1 << IGNITION_PIN);
     PORTB |= (1 << IGNITION_PIN);   // enable pull-up
+    PORTB &= ~(1 << MOSI_PIN);
+    PORTB &= ~(1 << MISO_PIN);
+    PORTB &= ~(1 << SCK_PIN);
 
     GIMSK |= (1 << PCIE);           // Enable Pin Change Interrupts
     PCMSK |= (1 << IGNITION_PIN);   // Use PB4 as interrupt pin
@@ -66,11 +80,88 @@ void switch_power(enum power power)
     }
 }
 
+void handle_state_init()
+{
+    if(ignition_on()) {
+        switch_power(on);
+        PORTB &= ~(1 << MOSI_PIN);
+        PORTB &= ~(1 << MISO_PIN);
+        PORTB &= ~(1 << SCK_PIN);
+        current_state = state_on;
+    } else {
+        shutdown_expire = tick + SHUTDOWN_TIME_MS;
+        PORTB |= (1 << MOSI_PIN);
+        PORTB |= (1 << MISO_PIN);
+        PORTB |= (1 << SCK_PIN);
+        current_state = state_shutdown;
+    }
+}
+
+void handle_state_on()
+{
+    if(!ignition_on()) {
+        shutdown_expire = tick + SHUTDOWN_TIME_MS;
+        PORTB |= (1 << MOSI_PIN);
+        PORTB |= (1 << MISO_PIN);
+        PORTB |= (1 << SCK_PIN);
+        current_state = state_shutdown;
+    }
+}
+
+void handle_state_shutdown()
+{
+    if(shutdown_expire < tick) {
+        if(power_on()) {
+            switch_power(off);
+        }
+        if(ignition_on()) {
+            guard_expire = tick + GUARD_TIME_MS;
+            current_state = state_guard;
+        } else {
+            current_state = state_off;
+            sleep_enable();
+            sleep_cpu();
+            sleep_disable();
+        }
+    }
+}
+
+void handle_state_guard()
+{
+    if(guard_expire < tick) {
+        if(ignition_on()) {
+            switch_power(on);
+            PORTB &= ~(1 << MOSI_PIN);
+            PORTB &= ~(1 << MISO_PIN);
+            PORTB &= ~(1 << SCK_PIN);
+            current_state = state_on;
+        } else {
+            current_state = state_off;
+            sleep_enable();
+            sleep_cpu();
+            sleep_disable();
+        }
+    }
+}
+
+void handle_state_off()
+{
+    if(ignition_on()) {
+        switch_power(on);
+        PORTB &= ~(1 << MOSI_PIN);
+        PORTB &= ~(1 << MISO_PIN);
+        PORTB &= ~(1 << SCK_PIN);
+        current_state = state_on;
+    }
+}
+
 int main(void)
 {
-    uint32_t shutdown_expire = 0;
+    current_state = state_init;
     tick = 0;
-    is_shutdown = false;
+    shutdown_expire = 0;
+    guard_expire = 0;
+
     setup_gpio();
     setup_timer0();
 
@@ -82,31 +173,16 @@ int main(void)
     sei();
 
     while(1) {
-        if(ignition_on()) {
-            if(!power_on()) {
-                switch_power(on);
-                is_shutdown = false;
-            }
-            sleep_enable();
-            sleep_cpu();
-            sleep_disable();
-        } else {
-            if(!is_shutdown) {
-                is_shutdown = true;
-                shutdown_expire = tick + SHUTDOWN_TIME_MS;
-            }
-            else {
-                if(shutdown_expire < tick) {
-                    if(power_on()) {
-                        switch_power(off);
-                    }
-                    // setup_watchdog();
-                    sleep_enable();
-                    sleep_cpu();
-                    sleep_disable();
-                    // wdt_disable();
-                }
-            }
+        if(current_state == state_init) {
+            handle_state_init();
+        } else if(current_state == state_on) {
+            handle_state_on();
+        } else if(current_state == state_shutdown) {
+            handle_state_shutdown();
+        } else if(current_state == state_guard) {
+            handle_state_guard();
+        } else if(current_state == state_off) {
+            handle_state_off();
         }
     }