Add christmas edition

christmas/AdAstra/src/hardware_access/eeprom/eeprom.c

@@ -0,0 +1,75 @@
+#include "eeprom.h"
+
+#include <stdbool.h>
+#include <avr/interrupt.h>
+#include <avr/eeprom.h>
+
+#include "bitwise.h"
+
+
+uint8_t memory[STORAGE_SIZE] EEMEM;
+
+static volatile struct {
+	uint8_t* buffer;
+	uint8_t positon;
+	bool isWriting;
+	OnEEPROMFinished onFinished;
+} eeprom;
+
+uint8_t loadByteEEPROM(uint8_t* address) {
+	while(getBit(EECR, EEPE)) {}
+	
+	EEAR = (uint16_t)address;
+	setBit(EECR, EERE);
+	return EEDR;
+}
+
+uint8_t loadSavedByteEEPROM(uint8_t address) {
+	return loadByteEEPROM(memory + address);
+}
+
+uint16_t loadWordEEPROM(uint16_t const* address) {
+	uint16_t high = ((uint16_t)loadByteEEPROM((uint8_t*)address + 1)) << 8;
+	uint16_t low = (uint16_t)loadByteEEPROM((uint8_t*)address);
+	return high | low;
+}
+
+static inline void saveByteEEPROM(uint8_t* address, uint8_t byte) {
+	if (byte != loadByteEEPROM(address)) {
+		EEDR = byte;
+		setBit(EECR, EEMPE);
+		setBit(EECR, EEPE);
+	}
+}
+
+void enableWritingEEPROM() {
+	modifyBit(EECR, EERIE, eeprom.isWriting);
+}
+
+void disableWritingEEPROM() {
+	clearBit(EECR, EERIE);		// clear eeprom ready interrupt enable
+}
+
+bool asyncWriteEEPROM(uint8_t* buffer, OnEEPROMFinished onFinished) {
+	if (eeprom.isWriting) {
+		return false;
+	}
+
+	eeprom.buffer = buffer;
+	eeprom.onFinished = onFinished;
+	eeprom.positon = 0;
+	eeprom.isWriting = true;
+	setBit(EECR, EERIE);	// set eeprom ready interrupt
+
+	return true;
+}
+
+ISR(EE_RDY_vect) {	
+	saveByteEEPROM(memory + eeprom.positon, eeprom.buffer[eeprom.positon]);
+	
+	if (++eeprom.positon == STORAGE_SIZE) {
+		clearBit(EECR, EERIE);
+		eeprom.isWriting = false;
+		eeprom.onFinished(eeprom.buffer);
+	}
+}