Optimisation for RP2040

Adafruit_ILI9341.cpp

@@ -303,13 +303,53 @@ void Adafruit_ILI9341::setScrollMargins(uint16_t top, uint16_t bottom) {
 void Adafruit_ILI9341::setAddrWindow(uint16_t x1, uint16_t y1, uint16_t w,
                                      uint16_t h) {
   uint16_t x2 = (x1 + w - 1), y2 = (y1 + h - 1);
-  writeCommand(ILI9341_CASET); // Column address set
-  SPI_WRITE16(x1);
-  SPI_WRITE16(x2);
-  writeCommand(ILI9341_PASET); // Row address set
-  SPI_WRITE16(y1);
-  SPI_WRITE16(y2);
-  writeCommand(ILI9341_RAMWR); // Write to RAM
+#if defined(ARDUINO_ARCH_RP2040)
+  // Use optimised code if it is HARDWARE SPI
+  if (connection == 0) {
+    // Since the SPI functions do not terminate until transmission is complete
+    // a busy check is not needed.
+    // while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+    SPI_DC_LOW();          // Command mode
+    spi_set_format(spi0,  8, (spi_cpol_t)0, (spi_cpha_t)0, SPI_MSB_FIRST);
+    spi_get_hw(spi0)->dr = (uint32_t)ILI9341_CASET;
+
+    while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+    SPI_DC_HIGH();         // Data mode
+    spi_get_hw(spi0)->dr = (uint32_t)x1>>8;
+    spi_get_hw(spi0)->dr = (uint32_t)x1;
+    spi_get_hw(spi0)->dr = (uint32_t)x2>>8;
+    spi_get_hw(spi0)->dr = (uint32_t)x2;
+
+    while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+    SPI_DC_LOW();          // Command mode
+    spi_get_hw(spi0)->dr = (uint32_t)ILI9341_PASET;
+
+    while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+    SPI_DC_HIGH();         // Data mode
+    spi_get_hw(spi0)->dr = (uint32_t)y1>>8;
+    spi_get_hw(spi0)->dr = (uint32_t)y1;
+    spi_get_hw(spi0)->dr = (uint32_t)y2>>8;
+    spi_get_hw(spi0)->dr = (uint32_t)y2;
+
+    while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+    SPI_DC_LOW();          // Command mode
+    spi_get_hw(spi0)->dr = (uint32_t)ILI9341_RAMWR;
+
+    while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+    spi_set_format(spi0, 16, (spi_cpol_t)0, (spi_cpha_t)0, SPI_MSB_FIRST);
+    SPI_DC_HIGH();         // Data mode
+  }
+  else
+#endif
+  {
+    writeCommand(ILI9341_CASET); // Column address set
+    SPI_WRITE16(x1);
+    SPI_WRITE16(x2);
+    writeCommand(ILI9341_PASET); // Row address set
+    SPI_WRITE16(y1);
+    SPI_WRITE16(y2);
+    writeCommand(ILI9341_RAMWR); // Write to RAM
+  }
 }
 
 /**************************************************************************/
@@ -327,3 +367,81 @@ uint8_t Adafruit_ILI9341::readcommand8(uint8_t commandByte, uint8_t index) {
   sendCommand(0xD9, &data, 1); // Set Index Register
   return Adafruit_SPITFT::readcommand8(commandByte);
 }
+
+
+// Override Adafruit_GFX writePixel() for RP2040
+/*!
+    @brief  Draw a single pixel to the display at requested coordinates.
+            Not self-contained; should follow a startWrite() call.
+    @param  x      Horizontal position (0 = left).
+    @param  y      Vertical position   (0 = top).
+    @param  color  16-bit pixel color in '565' RGB format.
+*/
+#if defined(ARDUINO_ARCH_RP2040)
+void Adafruit_ILI9341::writePixel(int16_t x, int16_t y, uint16_t color) {
+
+  // If it is a TFT_HARD_SPI interface then use RP2040 optimised code
+  // otherwise use original code
+  if (connection == 0) {
+    if ((x >= 0) && (x < _width) && (y >= 0) && (y < _height)) {
+      // Since the SPI functions do not terminate until transmission is complete
+      // a busy check is not needed.
+      // while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+      SPI_DC_LOW();          // Command mode
+      spi_set_format(spi0,  8, (spi_cpol_t)0, (spi_cpha_t)0, SPI_MSB_FIRST);
+      spi_get_hw(spi0)->dr = (uint32_t)ILI9341_CASET;
+
+      while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+      SPI_DC_HIGH();
+      spi_get_hw(spi0)->dr = (uint32_t)x>>8;
+      spi_get_hw(spi0)->dr = (uint32_t)x;
+      spi_get_hw(spi0)->dr = (uint32_t)x>>8;
+      spi_get_hw(spi0)->dr = (uint32_t)x;
+
+      while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+      SPI_DC_LOW();          // Command mode
+      spi_get_hw(spi0)->dr = (uint32_t)ILI9341_PASET;
+
+      while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+      SPI_DC_HIGH();
+      spi_get_hw(spi0)->dr = (uint32_t)y>>8;
+      spi_get_hw(spi0)->dr = (uint32_t)y;
+      spi_get_hw(spi0)->dr = (uint32_t)y>>8;
+      spi_get_hw(spi0)->dr = (uint32_t)y;
+
+      while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+      SPI_DC_LOW();          // Command mode
+      spi_get_hw(spi0)->dr = (uint32_t)ILI9341_RAMWR;
+
+      while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+      SPI_DC_HIGH();
+      spi_get_hw(spi0)->dr = (uint32_t)color>>8;
+      spi_get_hw(spi0)->dr = (uint32_t)color;
+
+    /*
+      // Subsequent pixel reads work OK without draining the FIFO...
+      // Drain RX FIFO, then wait for shifting to finish (which may be *after*
+      // TX FIFO drains), then drain RX FIFO again
+      while (spi_is_readable(spi0))
+          (void)spi_get_hw(spi0)->dr;
+      while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS)
+          tight_loop_contents();
+      while (spi_is_readable(spi0))
+          (void)spi_get_hw(spi0)->dr;
+    //*/
+
+    //  Subsequent pixel reads work without this
+    //  spi_get_hw(spi0)->icr = SPI_SSPICR_RORIC_BITS;
+
+      while (spi_get_hw(spi0)->sr & SPI_SSPSR_BSY_BITS) {};
+
+      // Next call will start with 8 bit command so changing to 16 bit not needed here
+      //spi_set_format(spi0,  16, (spi_cpol_t)0, (spi_cpha_t)0, SPI_MSB_FIRST);
+    }
+  }
+  else {
+    Adafruit_SPITFT::writePixel(x, y, color);
+    return;
+  }
+}
+#endif

Adafruit_ILI9341.h

@@ -150,6 +150,11 @@ class Adafruit_ILI9341 : public Adafruit_SPITFT {
   void scrollTo(uint16_t y);
   void setScrollMargins(uint16_t top, uint16_t bottom);
 
+#if defined(ARDUINO_ARCH_RP2040)
+  // Override GFX for RP2040
+  void writePixel(int16_t x, int16_t y, uint16_t color);
+#endif
+
   // Transaction API not used by GFX
   void setAddrWindow(uint16_t x, uint16_t y, uint16_t w, uint16_t h);
 

README.md

@@ -1,3 +1,11 @@
+Raspberry PI Pico (RP2040) optimised to work with Earle Philhower's Arduino board package and my optimised fork of Adafruit_GFX here:
+
+https://github.com/Bodmer/Adafruit-GFX-Library
+
+
+
+
+
 # Adafruit ILI9341 Arduino Library [![Build Status](https://github.com/adafruit/Adafruit_ILI9341/workflows/Arduino%20Library%20CI/badge.svg)](https://github.com/adafruit/Adafruit_ILI9341/actions)[![Documentation](https://github.com/adafruit/ci-arduino/blob/master/assets/doxygen_badge.svg)](http://adafruit.github.io/Adafruit_ILI9341/html/index.html)
 
 This is a library for the Adafruit ILI9341 display products

examples/graphicstest/graphicstest.ino

@@ -19,19 +19,28 @@
 #include "Adafruit_ILI9341.h"
 
 // For the Adafruit shield, these are the default.
-#define TFT_DC 9
-#define TFT_CS 10
+//#define TFT_DC 9
+//#define TFT_CS 10
+
+// For Raspberry Pi Pico (RP2040)
+// TFT MISO/SDO     connects to Pico pin D0 (GPIO 0)
+// TFT MOSI/SDI     connects to Pico pin D3 (GPIO 3)
+// TFT CLK/SCK/SCLK connects to Pico pin D2 (GPIO 2) 
+#define TFT_CS   20  // Chip select control pin (GPIO 20)
+#define TFT_DC   18  // Data Command control pin (GPIO 18)
+#define TFT_RST  19  // Reset pin (GPIO 19)
 
 // Use hardware SPI (on Uno, #13, #12, #11) and the above for CS/DC
-Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC);
+//Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC);
 // If using the breakout, change pins as desired
 //Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_MOSI, TFT_CLK, TFT_RST, TFT_MISO);
+// If using Raspberry Pi Pico (RP2040)
+Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_RST);
 
 void setup() {
   Serial.begin(9600);
   Serial.println("ILI9341 Test!"); 
-
-  tft.begin();
+  tft.begin(64000000); // Can set SPI clock rate
 
   // read diagnostics (optional but can help debug problems)
   uint8_t x = tft.readcommand8(ILI9341_RDMODE);

examples/pictureEmbed/pictureEmbed.ino

@@ -27,20 +27,30 @@
 //#define TFT_CS 10
 
 // Feather 32u4 or M0 with TFT FeatherWing:
-#define TFT_DC 10
-#define TFT_CS  9
+//#define TFT_DC 10
+//#define TFT_CS  9
 // ESP8266:
 //#define TFT_DC 15
 //#define TFT_CS 0
+// Raspberry Pi Pico (RP2040)
+// TFT MISO/SDO     connects to Pico pin D0 (GPIO 0)
+// TFT MOSI/SDI     connects to Pico pin D3 (GPIO 3)
+// TFT CLK/SCK/SCLK connects to Pico pin D2 (GPIO 2) 
+#define TFT_CS   20  // Chip select control pin (GPIO 20)
+#define TFT_DC   18  // Data Command control pin (GPIO 18)
+#define TFT_RST  19  // Reset pin (GPIO 19)
+
 // Other boards (including Feather boards) may have other pinouts;
 // see learn.adafruit.com/adafruit-2-4-tft-touch-screen-featherwing/pinouts
 
-Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC);
+//Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC);
 // If using the breakout, change pins as desired
 //Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_MOSI, TFT_CLK, TFT_RST, TFT_MISO);
+// If using Raspberry Pi Pico (RP2040)
+Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_RST);
 
 void setup() {
-  tft.begin();
+  tft.begin(64000000); // Can set SPI clock rate
 }
 
 void loop(void) {