Intermediary commit. Nothing's working, everything is broken. Let's start over now...

src/player.cpp

@@ -0,0 +1,99 @@
+// Based on https://github.com/mpflaga/Arduino_Library-vs1053_for_SdFat/blob/master/src/vs1053_SdFat.cpp
+
+#include "player.h"
+#include "spi_master.h"
+
+Player::Player(SDCard* c) {
+	pinMode(XRESET, OUTPUT);
+	digitalWrite(XRESET, HIGH);
+	pinMode(DREQ, INPUT);
+
+	_init();
+}
+
+void Player::_reset() {
+	digitalWrite(XRESET, LOW);
+	delay(50);
+	digitalWrite(XRESET, HIGH);
+	delay(50);
+}
+
+void Player::_init() {
+	SPI.setClockDivider(SPI_CLOCK_DIV16);
+
+	_reset();
+	uint16_t result;
+	for(uint8_t x=0; x<255; x++) {
+		result = _read_register(SCI_MODE, 0, x);
+		if (result != 0) Serial.printf("Try %3d: 0x%04X\n", x, result);
+	}
+	delay(10);
+	/*_read_register(SCI_MODE, SPI_CLOCK_DIV16); // First read fails for some unknown reason...
+	_read_register(SCI_MODE, SPI_CLOCK_DIV16);
+	_read_register(SCI_STATUS, SPI_CLOCK_DIV16);
+
+	_read_register(SCI_STATUS, SPI_CLOCK_DIV16);
+
+
+	_read_register(SCI_MODE, SPI_CLOCK_DIV16);
+	_read_register(SCI_MODE, SPI_CLOCK_DIV16);
+	uint16_t response = _read_register(SCI_MODE, SPI_CLOCK_DIV16);
+	if (response != 0x4800) {
+		Serial.printf("Initialization failed. SCI_MODE was: 0x%04X. Expected: 0x4800\n", response);
+		return;
+	}*/
+	/*_write_register(SCI_CLOCKF, 0x6000); // Set multiplier to 3x
+	delay(10);
+	response = _read_register(SCI_CLOCKF);
+	if (response != 0x6000) {
+		Serial.printf("Initialization failed. SCI_CLOCKF was: 0x%04X. Expected: 0x6000\n", response);
+		return;
+	}*/
+	//Serial.println(result, HEX);
+}
+
+inline void Player::_wait() {
+	delayMicroseconds(100);
+	//Serial.print("Waiting for DREQ...");
+	while(!digitalRead(DREQ));
+	//Serial.printf(" done (%d cycles).\n", i);
+}
+
+uint16_t Player::_read_register(uint8_t address, uint32_t spi_speed, uint16_t t) {
+	Serial.printf("Try %03d, querying register 0x%02X...", t, address);
+	//SPI.setClockDivider(spi_speed);
+	if (t & (1<<1)) _wait();
+	SPIMaster::enable(PIN_VS1053_XCS);
+	if (t & (1<<2)) _wait();
+	//_wait();
+	SPI.transfer(CMD_READ);
+	if (t & (1<<3)) _wait();
+	SPI.transfer(address);
+	if (t & (1<<4)) _wait();
+	uint8_t b1 = SPI.transfer(0xFF);
+	if (t & (1<<5)) _wait();
+	uint8_t b2 = SPI.transfer(0xFF);
+	if (t & (1<<6)) _wait();
+
+	uint16_t result = b1 << 8 | b2;
+	Serial.printf("Response: 0x%02X 0x%02X -> 0x%04X\n", b1, b2, result);
+	if (t & (1<<7)) delay(10);
+
+	//_wait();
+	//SPIMaster::disable();
+
+	return result;
+}
+
+void Player::_write_register(uint8_t address, uint16_t value, uint32_t spi_speed) {
+	Serial.printf("Writing to register 0x%02X...", address);
+	SPI.setClockDivider(spi_speed);
+	SPIMaster::enable(PIN_VS1053_XCS);
+	SPI.transfer(CMD_WRITE);
+	SPI.transfer(address);
+	SPI.transfer(value >> 8);
+	SPI.transfer(value & 0xFF);
+	_wait();
+	SPIMaster::disable();
+	Serial.println(" done.");
+}