Initial Check in.

IoTuz.cpp

@@ -0,0 +1,240 @@
+/*************************************************** 
+  IoTuz class to provide basic driver methods for the ESP32 based IoTuz board
+  from LCA 2017: https://github.com/CCHS-Melbourne/iotuz-esp32-hardware
+
+  By Marc MERLIN <marc_soft@merlins.org>
+
+  License: Apache 2.0.
+
+  Required libraries:
+  - Wire.h to support the pcf8574 port expander
+
+ ****************************************************/
+
+#include <Wire.h>
+#include "IoTuz.h"
+
+volatile int16_t encoder0Pos = 0;
+
+// These need to be global because all sketches use them as a global
+// tft adafruit library (games use tft2 a separate library, for which we skip the init
+// since the adafruit init works fine for both)
+Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_RST);
+// faster, better lib, that doesn't work yet.
+//ILI9341_t3 tft = ILI9341_t3(TFT_CS, TFT_DC, TFT_RST);
+
+// If you are lacking the ESP32 patch, you will get no error, but the LEDs will not work
+Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUMPIXELS, RGB_LED_PIN, NEO_GRB + NEO_KHZ800);
+
+// ADXL345
+Adafruit_ADXL345_Unified accel = Adafruit_ADXL345_Unified(12345);
+
+// Until further notice, there is a hack to get HW SPI be as fast as SW SPI:
+// in espressif/esp32/cores/esp32/esp32-hal.h after the first define, add
+// #define CONFIG_DISABLE_HAL_LOCKS 1
+// Use with caution, this may cause unknown issues
+
+void read_encoder_ISR() 
+{
+    static uint8_t old_AB = 0;
+    // grey code
+    // http://hades.mech.northwestern.edu/index.php/Rotary_Encoder
+    // also read up on 'Understanding Quadrature Encoded Signals'
+    // https://www.pjrc.com/teensy/td_libs_Encoder.html
+    // another interesting lib: https://github.com/0xPIT/encoder/blob/arduino/ClickEncoder.cpp
+    static int8_t enc_states[] = {0,-1,1,0,1,0,0,-1,-1,0,0,1,0,1,-1,0};
+
+    old_AB <<= 2;
+    old_AB |= ((digitalRead(ENCODERB_PIN))?(1<<1):0) | ((digitalRead(ENCODERA_PIN))?(1<<0):0);
+    encoder0Pos += ( enc_states[( old_AB & 0x0f )]);
+}
+
+// Talking to the port expander:
+// I2C/TWI success (transaction was successful).
+#define ku8TWISuccess    0
+// I2C/TWI device not present (address sent, NACK received).
+#define ku8TWIDeviceNACK 2
+// I2C/TWI data not received (data sent, NACK received).
+#define ku8TWIDataNACK   3
+// I2C/TWI other error.
+#define ku8TWIError      4
+void IoTuz::pcf8574_write_(uint8_t dt)
+{
+    uint8_t error;
+
+    Wire.beginTransmission(I2C_EXPANDER);
+    // Serial.print("Writing to I2CEXP: ");
+    // Serial.println(dt);
+    Wire.write(dt);
+    error = Wire.endTransmission();
+    if (error != ku8TWISuccess) {
+	    // FIXME: do something here if you like
+    }
+}
+
+// To clear bit #7, send 128
+void IoTuz::i2cexp_clear_bits(uint8_t bitfield)
+{
+    // set bits to clear to 0, all other to 1, binary and to clear the bits
+    _i2cexp &= (~bitfield);
+    pcf8574_write_(_i2cexp);
+}
+
+// To set bit #7, send 128
+void IoTuz::i2cexp_set_bits(uint8_t bitfield)
+{
+    _i2cexp |= bitfield;
+    pcf8574_write_(_i2cexp);
+}
+
+uint8_t IoTuz::i2cexp_read()
+{
+    // For read to work, we must have sent 1 bits on the ports that get used as input
+    // This is done by i2cexp_clear_bits called in setup.
+    Wire.requestFrom(I2C_EXPANDER, 1);	// FIXME: deal with returned error here?
+    while (Wire.available() < 1) ;
+    uint8_t read = ~Wire.read();	// Apparently one has to invert the bits read
+    // When no buttons are pushed, this returns 0x91, which includes some ports
+    // we use as output, so we do need to filter out the ports used as read.
+    // Serial.println(read, HEX);
+    return read;
+}
+
+int16_t IoTuz::read_encoder() 
+{
+    return encoder0Pos;
+}
+
+bool IoTuz::encoder_changed() {
+    static int16_t old_encoder0Pos = 0;
+    if (encoder0Pos != old_encoder0Pos)
+    {
+	old_encoder0Pos = encoder0Pos;
+	return true;
+    }
+    return false;
+}
+
+ButtState IoTuz::read_encoder_button() 
+{
+    static bool butEnc = false;
+    uint8_t butt_state = i2cexp_read() & I2CEXP_ENC_BUT;
+
+    if (butt_state && !butEnc)
+    {
+	butEnc = true;
+	//Serial.println("Encoder Button Pushed");
+	return ENC_PUSHED;
+    }
+    if (!butt_state && butEnc)
+    {
+	butEnc = false;
+	//Serial.println("Encoder Button Released");
+	return ENC_RELEASED;
+    }
+    return (butt_state?ENC_DOWN:ENC_UP);
+}
+
+// True turns the BL on
+void IoTuz::screen_bl(bool state) {
+    state ? i2cexp_clear_bits(I2CEXP_LCD_BL_CTR) : i2cexp_set_bits(I2CEXP_LCD_BL_CTR);
+}
+
+IoTuz::IoTuz()
+{
+    // Any write to I2CEXP should contain those mask bits so allow reads to work later
+    _i2cexp = I2CEXP_IMASK;
+
+    pinMode (ENCODERA_PIN, INPUT_PULLUP);
+    pinMode (ENCODERB_PIN, INPUT_PULLUP);
+
+    pinMode(SPI_MOSI, OUTPUT);
+    pinMode(SPI_MISO, INPUT);
+    pinMode(SPI_CLK, OUTPUT);
+
+    // Joystick Setup
+    pinMode(JOYSTICK_BUT_PIN, INPUT_PULLUP);
+
+    // TFT Setup
+    pinMode(TFT_CS, OUTPUT);
+    pinMode(TFT_DC, OUTPUT);
+    pinMode(TFT_RST, OUTPUT);
+}
+
+void IoTuz::begin()
+{
+    Serial.begin(115200);
+    Serial.println("Serial Begin");
+
+    // required for i2exp to work
+    Wire.begin();
+
+    // Hardware SPI on ESP32 is actually slower than software SPI. Giving 80Mhz
+    // here does not make things any faster. There seems to be a fair amount of
+    // overhead in the fancier hw SPI on ESP32 which is designed to send more than
+    // one byte at the time, and only ends up sending one byte when called from an
+    // arduino library.
+    // Sadly, using software SPI in the adafruit library would prevent SPI from working
+    // in the touch screen code which only supports hardware SPI
+    // The TFT code runs at 24Mhz as per below, but testing shows that any speed over 2Mhz
+    // seems ignored and taken down to 2Mhz
+    //SPI.beginTransaction(SPISettings(24000000, MSBFIRST, SPI_MODE0));
+
+    // Talking to the touch screen can only work at 2Mhz, and both drivers change the SPI
+    // speed before sending data, so this works transparently.
+
+    // ESP32 requires an extended begin with pin mappings (which is not supported by the
+    // adafruit library), so we do an explicit begin here and then the other SPI libraries work
+    // with hardware SPI as setup here (they will do a second begin without pin mappings and
+    // that will be ignored).
+    SPI.begin(SPI_CLK, SPI_MISO, SPI_MOSI);
+
+    // Turn off TFT by default. 
+    // Note this also initializes the read bits on PCF8574 by setting them to 1 as per I2CEXP_IMASK
+    i2cexp_set_bits(I2CEXP_LCD_BL_CTR);
+
+    Serial.println("ILI9341 Test!"); 
+    tft.begin();
+    // read diagnostics (optional but can help debug problems)
+    uint8_t x = tft.readcommand8(ILI9341_RDMODE);
+    Serial.print("Display Power Mode: 0x"); Serial.println(x, HEX);
+    x = tft.readcommand8(ILI9341_RDMADCTL);
+    Serial.print("MADCTL Mode: 0x"); Serial.println(x, HEX);
+    x = tft.readcommand8(ILI9341_RDPIXFMT);
+    Serial.print("Pixel Format: 0x"); Serial.println(x, HEX);
+    x = tft.readcommand8(ILI9341_RDIMGFMT);
+    Serial.print("Image Format: 0x"); Serial.println(x, HEX);
+    x = tft.readcommand8(ILI9341_RDSELFDIAG);
+    Serial.print("Self Diagnostic: 0x"); Serial.println(x, HEX); 
+    tft.setRotation(3);
+    tftw = tft.width(), tfth = tft.height();
+    Serial.print("Resolution: "); Serial.print(tftw); 
+    Serial.print(" x "); Serial.println(tfth);
+    Serial.println(F("Done!"));
+
+
+    // Init Accel
+    if(!accel.begin()) {
+	/* There was a problem detecting the ADXL345 ... check your connections */
+	Serial.println("Ooops, no ADXL345 detected ... Check your wiring!");
+	while(1);
+    }
+    accel.setRange(ADXL345_RANGE_16_G);
+    sensor_t sensor;
+    accel.getSensor(&sensor);
+    Serial.println("------------------------------------");
+    Serial.print  ("Sensor:       "); Serial.println(sensor.name);
+    Serial.print  ("Driver Ver:   "); Serial.println(sensor.version);
+    Serial.print  ("Unique ID:    "); Serial.println(sensor.sensor_id);
+    Serial.print  ("Max Value:    "); Serial.print(sensor.max_value); Serial.println(" m/s^2");
+    Serial.print  ("Min Value:    "); Serial.print(sensor.min_value); Serial.println(" m/s^2");
+    Serial.print  ("Resolution:   "); Serial.print(sensor.resolution); Serial.println(" m/s^2");  
+    Serial.println("------------------------------------");
+    Serial.println("");
+
+    // Initialize rotary encoder reading and decoding
+    attachInterrupt(ENCODERA_PIN, read_encoder_ISR, CHANGE);
+    attachInterrupt(ENCODERB_PIN, read_encoder_ISR, CHANGE);
+}
+
+// vim:sts=4:sw=4

IoTuz.h

@@ -0,0 +1,141 @@
+#ifndef IOTUZ_H
+#define IOTUZ_H
+
+#include <Wire.h>
+#include <SPI.h>
+
+#include <Adafruit_GFX.h>
+// Support for LCD screen
+// The latest version of that library may not be up to date and miss a patch for ESP32
+// which will cause a compilation error:
+// Adafruit_ILI9341.cpp:113:3: error: 'mosiport' was not declared in this scope
+// If so, get the latest version from github, or just patch this single line
+// https://github.com/adafruit/Adafruit_ILI9341/blob/master/Adafruit_ILI9341.cpp#L98
+#include <Adafruit_ILI9341.h>
+// faster, better lib, that doesn't work yet.
+//#include <ILI9341_t3.h>
+
+// https://learn.adafruit.com/adafruit-neopixel-uberguide/
+// Support for APA106 RGB LEDs
+// APA106 is somewhat compatible with WS2811 or WS2812 (well, maybe not 100%, but close enough to work)
+// I have patched the Adafruit library to support ESP32. If that hasn't been merged yet, see this patch
+// https://github.com/adafruit/Adafruit_NeoPixel/pull/125
+// If you do NOT apply my patch, the LEDS WILL NOT WORK
+#include "Adafruit_NeoPixel.h"
+
+// Accelerometer
+#include <Adafruit_Sensor.h>
+#include <Adafruit_ADXL345_U.h>
+
+
+// https://github.com/CCHS-Melbourne/iotuz-esp32-hardware/wiki has hardware mapping details
+/*
+I2C addresses:
+Audio:  0x1A
+IO_EXP: 0x20 => Spec sheet says 
+"To enter the Read mode the master (microcontroller) addresses the slave
+device and sets the last bit of the address byte to logic 1 (address byte read)"
+The Wire lib automatically uses the right I/O port for read and write.
+ADXL:   0x53
+BME230: 0x77 (Temp/Humidity/Pressure)
+*/
+
+
+
+// TFT + Touch Screen Setup Start
+// These are the minimal changes from v0.1 to get the LCD working
+#define TFT_DC 4
+#define TFT_CS 19
+#define TFT_RST 32
+// SPI Pins are shared by TFT, touch screen, SD Card
+#define SPI_MISO 12
+#define SPI_MOSI 13
+#define SPI_CLK 14
+
+// APA106 LEDs
+#define RGB_LED_PIN 23
+#define NUMPIXELS 2
+
+// LCD brightness control and touchscreen CS are behind the port
+// expander, as well as both push buttons
+#define I2C_EXPANDER 0x20	//0100000 (7bit) address of the IO expander on i2c bus
+
+/* Port expander PCF8574, access via I2C on */
+#define I2CEXP_ACCEL_INT    0x01	// (In)
+#define I2CEXP_A_BUT	    0x02	// (In)
+#define I2CEXP_B_BUT	    0x04	// (In)
+#define I2CEXP_ENC_BUT	    0x08	// (In)
+#define I2CEXP_SD_CS	    0x10	// (Out)
+#define I2CEXP_TOUCH_INT    0x20	// (In)
+#define I2CEXP_TOUCH_CS	    0x40	// (Out)
+#define I2CEXP_LCD_BL_CTR   0x80	// (Out)
+
+// Dealing with the I/O expander is a bit counter intuitive. There is no difference between a
+// write meant to toggle an output port, and a write designed to turn off pull down resistors and trigger
+// a read request.
+// The write just before the read should have bits high on the bits you'd like to read back, but you
+// may get high bits back on other bits you didn't turn off the pull down resistor on. This is normal.
+// Just filter out the bits you're trying to get from the value read back and keep in mind that when
+// you write, you should still send the right bit values for the output pins.
+// This is all stored in i2cexp which we initialize to the bits used as input:
+#define I2CEXP_IMASK ( I2CEXP_ACCEL_INT + I2CEXP_A_BUT + I2CEXP_B_BUT + I2CEXP_ENC_BUT + I2CEXP_TOUCH_INT )
+
+// This is calibration data for the raw touch data to the screen coordinates
+#define TS_MINX 320
+#define TS_MINY 220
+#define TS_MAXX 3920
+#define TS_MAXY 3820
+#define MINPRESSURE 400
+#define MAXPRESSURE 3000
+
+// Joystick Setup
+#define JOYSTICK_X_PIN 39
+#define JOYSTICK_Y_PIN 34
+#define JOYSTICK_BUT_PIN 0
+
+// Center on my IoTuz board (not used anymore)
+#define JOYSTICK_CENTERX  1785
+#define JOYSTICK_CENTERY  1854
+
+#define ENCODERA_PIN 15
+#define ENCODERB_PIN 36
+
+extern Adafruit_ILI9341 tft;
+extern Adafruit_NeoPixel pixels; 
+extern Adafruit_ADXL345_Unified accel;
+
+
+typedef enum {
+    ENC_DOWN = 0,
+    ENC_PUSHED = 1,
+    ENC_UP = 2,
+    ENC_RELEASED = 3,
+
+} ButtState;
+
+class IoTuz {
+  public:
+    IoTuz();
+
+    // tft_width, tft_height, calculated in setup after tft init
+    uint16_t tftw, tfth;
+
+    void i2cexp_clear_bits(uint8_t);
+    void i2cexp_set_bits(uint8_t);
+    uint8_t i2cexp_read();
+    void screen_bl(bool);
+    int16_t read_encoder();
+    bool encoder_changed();
+    ButtState read_encoder_button();
+    void begin();
+
+  private:
+    uint8_t _i2cexp;
+    void pcf8574_write_(uint8_t);
+};
+
+
+
+#endif
+
+// vim:sts=4:sw=4