some refactoring,

minor code changes
added a small class for SNESController reading

Platforms.h

@@ -9,9 +9,11 @@
 #define WROOM32_DEVKIT			32
 #define TTGO					33
 
+#define TEENSY_41				41
 
 #define ESP8266		(PLATFORM == WEMOS_D1_MINI) || (PLATFORM == NODE_MCU)
 #define ESP32		(PLATFORM == WROOM32_DEVKIT) || (PLATFORM == TTGO)
+#define TEENSY		(PLATFORM == TEENSY_41)
 
 #ifndef PLATFORM
 	#error "PLATFORM compile time variable not defined"
@@ -29,9 +31,13 @@
 	#define DELAY_US(us)		os_delay_us(us)
 	#define IN_FLASH			ICACHE_FLASH_ATTR
 	
+#elif (TEENSY)
+
+	#pragma message "Using Teensy"
+
 #else
 
-	#error "unsupported platform";
+	#error "Platforms.h: unsupported platform";
 	
 #endif
 

ext/ctrl/SNESController.h

@@ -0,0 +1,122 @@
+#ifndef SNES_CONTROLLER_H
+#define SNES_CONTROLLER_H
+
+#include "../../io/GPIO.h"
+
+
+/** https://fpgalover.com/images/manuals/SNES/time.JPG */
+template <int PIN_LATCH, int PIN_DATA, int PIN_CLK> class SNESController {
+	
+public:
+
+	union State {
+		
+		uint16_t raw;
+		
+		State() : raw(0) {}
+		
+		State(uint16_t raw) : raw(raw) {}
+		
+		struct {
+			
+			uint8_t dummy1 : 1;
+			uint8_t dummy2 : 1;
+			uint8_t dummy3 : 1;
+			uint8_t dummy4 : 1;
+			uint8_t r : 1;
+			uint8_t l : 1;
+			uint8_t x : 1;
+			uint8_t a : 1;
+			
+			uint8_t right : 1;
+			uint8_t left : 1;
+			uint8_t down : 1;
+			uint8_t up : 1;
+			uint8_t start : 1;
+			uint8_t select : 1;
+			uint8_t y : 1;
+			uint8_t b : 1;
+			
+		};
+		
+		bool operator != (const State o) const {return raw != o.raw;}
+		
+		/** write current state into the given 12+1 char* */
+		void toString(char* dst) {
+			dst[ 0] = !r		? 'R' : ' ';
+			dst[ 1] = !l		? 'L' : ' ';
+			dst[ 2] = !x		? 'X' : ' ';
+			dst[ 3] = !a		? 'A' : ' ';
+			dst[ 4] = !right	? 'r' : ' ';
+			dst[ 5] = !left		? 'l' : ' ';
+			dst[ 6] = !down		? 'd' : ' ';
+			dst[ 7] = !up		? 'u' : ' ';
+			dst[ 8] = !start	? 'S' : ' ';
+			dst[ 9] = !select	? 's' : ' ';
+			dst[10] = !y		? 'Y' : ' ';
+			dst[11] = !b		? 'B' : ' ';
+			dst[12] = 0;
+		}
+			
+		
+	};
+
+public:
+
+	/** ctor */
+	SNESController() {
+		MyGPIO::setInput(PIN_DATA);
+		MyGPIO::setOutput(PIN_LATCH);
+		MyGPIO::setOutput(PIN_CLK);		
+	}
+	
+	
+	/** read the current state from the controller */
+	State read() {
+		
+		// latch the current data (remember state)
+		latch();
+		
+		// read all 16 data bits
+		uint16_t res = 0;
+		for (uint8_t i = 0; i < 16; ++i) {
+			res <<= 1;
+			res |= readBit();
+		}
+		
+		// wrap
+		return State(res);	
+		
+	}
+	
+private:
+
+	void latch() {
+		
+		// ensure CLK is HIGH
+		MyGPIO::set(PIN_CLK);
+		
+		// send latch impulse
+		MyGPIO::set(PIN_LATCH);
+		wait();
+		MyGPIO::clear(PIN_LATCH);
+		wait();
+		
+	}
+	
+	uint8_t readBit() {
+		MyGPIO::set(PIN_CLK);
+		wait();
+		MyGPIO::clear(PIN_CLK);
+		uint8_t res = MyGPIO::get(PIN_DATA);
+		wait();
+		return res;
+	}
+	
+	void wait() {
+		for (uint8_t i = 0; i < 128; ++i) {asm("nop");}
+	}
+	
+};
+
+#endif 

ext/lcd/ST7735.h

@@ -230,7 +230,7 @@ private:
 
 public:
 
-	void flush(const uint16_t* data) {
+	void startWrite() {
 		
 		select();
 
@@ -249,6 +249,22 @@ public:
 		sendCommand(ST7735_RAMWR);
 
 		modeData();
+		
+	}
+
+	void writePixel(const uint16_t rgb) {
+		spi.writeByte(rgb >> 0);
+		spi.writeByte(rgb >> 8);
+	}
+
+	void stopWrite() {
+		deselect();
+	}
+
+	void flush(const uint16_t* data) {
+
+		startWrite();
+		
 		/*
 		for (int i = 0; i < (V*H); ++i) {
 			const uint16_t color = data[i];
@@ -262,7 +278,7 @@ public:
 		spi.write((const uint8_t*)data, V*H*sizeof(uint16_t));
 		
 
-		deselect();
+		stopWrite();
 
 	}
 

ext/sens/INA219.h

@@ -19,7 +19,7 @@ public:
 
 	struct Voltages {
 		
-		int		vShunt;	// in uV * 10(!!!)
+		int16_t	vShunt;	// in uV * 10(!!!)
 		int16_t	vBus;	// in mV
 		
 		int getMilliAmps(int shunt_milliOhm) const {
@@ -68,24 +68,24 @@ public:
 		const uint8_t pg =		(cfg & 0b01100000000000) >> 11;
 		const uint8_t brng =	(cfg & 0b10000000000000) >> 13;
 		printf("INA219\n");
-		printf("- Mode: %d", mode);
+		printf("- Mode: %d\n", mode);
-		printf("- SADC: %d", sadc);
+		printf("- SADC: %d\n", sadc);
-		printf("- BADC: %d", badc);
+		printf("- BADC: %d\n", badc);
-		printf("PG (shunt divider) %d", (1<<pg));
+		printf("PG (shunt divider) %d\n", (1<<pg));
-		if (brng)	{printf("- bus voltage range [0:16]");}
+		if (brng)	{printf("- bus voltage range [0:16]\n");}
-		else		{printf("- bus voltage range [0:32]");}		
+		else		{printf("- bus voltage range [0:32]\n");}		
 	}
 	
 private:
 
 	/** convert to bytes into a mV reading */
 	int16_t getBusVoltage(const uint8_t* buf) {
-		return (getU16(buf) >> 3) * 4;				// lower 3 bits are status indicators -> remove, the LSB equals 4 mV -> * 4
+		return (int16_t)((getU16(buf) >> 3) * 4);			// lower 3 bits are status indicators -> remove, the LSB equals 4 mV -> * 4
 	}
 	
 	/** convert to bytes into a uV reading */
-	int getShuntVoltage(const uint8_t* buf) {
+	int16_t getShuntVoltage(const uint8_t* buf) {	
-		return ((int)((int16_t)getU16(buf)));		// NOTE: LSB = 10 uV
+		return (int16_t)getU16(buf);						// NOTE: LSB = 10 uV
 	}
 	
 	uint16_t getU16(const uint8_t* buf) {

io/GPIO.h

@@ -178,9 +178,27 @@
 
 	};
 
+#elif TEENSY
+
+	struct MyGPIO {
+		
+	public:
+	
+		static void setOutput(uint8_t pin)	{pinMode(pin, OUTPUT);}
+		
+		static void setInput(uint8_t pin)	{pinMode(pin, INPUT);}
+		
+		static void clear(uint8_t pin)		{digitalWriteFast(pin, 0);}
+		
+		static void set(uint8_t pin)		{digitalWriteFast(pin, 1);}
+		
+		static uint8_t get(uint8_t pin)		{return digitalReadFast(pin);}
+		
+	};
+	
 #else
 
-	#error "unsupported platform";
+	#error "GPIO: unsupported platform";
 
 #endif
 

io/HardSPI.h

@@ -17,7 +17,7 @@
 template <int PIN_NUM_MISO, int PIN_NUM_MOSI, int PIN_NUM_CLK> class HardSPI {
 //class HardSPI {
 
-	static constexpr int MAX_LEN = 4000;
+	static constexpr int MAX_LEN = 8192;
 
 	spi_device_handle_t spi;
 
@@ -57,7 +57,7 @@ private:
 
 		// DEVICE specific options
 		memset(&devcfg, 0, sizeof(devcfg));
-		devcfg.clock_speed_hz = 10 * 1000 * 1000;
+		devcfg.clock_speed_hz = 20 * 1000 * 1000;	// IMPORTANT!
 		devcfg.mode = 0;
 		devcfg.spics_io_num = -1;//PIN_NUM_CS;		// currently not used
 		devcfg.queue_size = 2;
@@ -104,6 +104,7 @@ public:
 
 	}
 
+
 	void read(uint8_t* dst, size_t len) {
 
 		// sanity check

io/I2S.h

@@ -28,13 +28,16 @@ public:
 			cfg.mode = static_cast<i2s_mode_t>(I2S_MODE_MASTER | I2S_MODE_TX);
 		#endif
 
-		cfg.dma_buf_count = 6;
+	//	cfg.dma_buf_count = 6;
+	//	cfg.dma_buf_len = 128;
+
+		cfg.dma_buf_count = 16;
 		cfg.dma_buf_len = 128;
 
 		cfg.sample_rate = 44100;
 		cfg.bits_per_sample = I2S_BITS_PER_SAMPLE_16BIT;
 		cfg.channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT;                          //2-channels
-		cfg.communication_format = I2S_COMM_FORMAT_I2S_MSB;
+		cfg.communication_format = I2S_COMM_FORMAT_STAND_I2S;//I2S_COMM_FORMAT_I2S_MSB;
 
 
 		cfg.intr_alloc_flags = 0;                                                  //Default interrupt priority
@@ -72,9 +75,9 @@ public:
 	}
 
 	/** add the given samples for playback. returns the number of added samples, which might be less in case of timeouts */
-	size_t add(const uint8_t* data, const size_t len) {
+	size_t add(const uint8_t* data, const size_t len_bytes) {
 		size_t written;
-		i2s_write(port, data, len, &written, portMAX_DELAY);
+		i2s_write(port, data, len_bytes, &written, portMAX_DELAY);
 		return written;
 	}
 

io/SoftSPI.h

@@ -88,7 +88,7 @@ public:
 		writeByte((word>>0)&0xFF);
 	}
 
-	void IRAM_ATTR writeByte(uint8_t byte) {
+	inline void IRAM_ATTR writeByte(uint8_t byte) {
 		writeBit(byte & BIT( 7));
 		writeBit(byte & BIT( 6));
 		writeBit(byte & BIT( 5));