Pi pico explorer display

[omikron88]

Hello, How to make Arduino_GFX work with Pi pico Explorer?

https://shop.pimoroni.com/products/pico-explorer-base

It uses the display that is supported I think, main problem is, that it uses MISO pin as Data/Command for display.

https://cdn.shopify.com/s/files/1/0174/1800/files/pico_explorer_schematic.pdf?v=1619077703

Is there a workaround for this?

Tom

[moononournation]

I think you may follow their source use PIN_UNUSED:

static const unsigned int SPI_BG_FRONT_CS = 17;
static const unsigned int SPI_DEFAULT_MOSI = 19;
static const unsigned int SPI_DEFAULT_MISO = 16;
static const unsigned int SPI_DEFAULT_SCK = 18;
static const uint8_t PIN_UNUSED   = UINT8_MAX;
Arduino_DataBus *bus = new Arduino_RPiPicoSPI(SPI_DEFAULT_MISO /* DC */, SPI_BG_FRONT_CS /* CS */, SPI_DEFAULT_SCK /* SCK */, SPI_DEFAULT_MOSI /* MOSI */, PIN_UNUSED /* MISO */, spi0 /* spi */);

[omikron88]

I had to create new derived class, with changed SPI initialisation. Because miso pin is used as dc and not miso.

void Explorer_RPiPicoSPI::begin(int32_t speed / = 0 /, int8_t dataMode / = -1 /) { // set SPI parameters _speed = speed ? speed : SPI_DEFAULT_FREQ; _dataMode = (dataMode >= 0) ? dataMode : SPI_MODE0; _spis = SPISettings(_speed, _bitOrder, _dataMode);

// set pin mode pinMode(_dc, OUTPUT); digitalWrite(_dc, HIGH); // Data mode if (_cs >= 0) { pinMode(_cs, OUTPUT); digitalWrite(_cs, HIGH); // disable chip select }

if (_miso >= 0) { gpio_set_function(_miso, GPIO_FUNC_SPI); }

gpio_set_function(_sck, GPIO_FUNC_SPI); gpio_set_function(_mosi, GPIO_FUNC_SPI);

// set fastIO variables _dcPinMask = digitalPinToBitMask(_dc); _dcPortSet = (PORTreg_t)&sio_hw->gpio_set; _dcPortClr = (PORTreg_t)&sio_hw->gpio_clr;

if (_cs >= 0) { _csPinMask = digitalPinToBitMask(_cs); _csPortSet = (PORTreg_t)&sio_hw->gpio_set; _csPortClr = (PORTreg_t)&sio_hw->gpio_clr; }

spi_init(_spi, _spis.getClockFreq()); spi_set_format(_spi, 8, SPI_CPOL_0, SPI_CPHA_0, SPI_MSB_FIRST); }

Now the display blinks a little at initialisation, but it still show nothing. Is it possible, that the display needs different init commands?

The init calls are:

Arduino_DataBus bus = new Explorer_RPiPicoSPI(PIN_SPI0_MISO / dc /, PIN_SPI0_SS / cs /, PIN_SPI0_SCK / sck /, PIN_SPI0_MOSI / mosi /, -1 / miso /, spi0 / spi /); Arduino_GFX gfx = new Arduino_ST7789(bus, -1 / RST /, 2 / rotation /, true / IPS /, 240 / width /, 240 / height /, 0 / col offset 1 /, 80 / row offset 1 /);

//------------------------------------------------------------------------------ void setup() { Serial.begin(9600); while (!Serial) { ; }

// Wire.setSDA(SDA); // Wire.setSCL(SCL); // Wire.setClock(40000); // Wire.begin();

// SPI.setRX(MISO); // SPI.setTX(MOSI); // SPI.setSCK(SCK); // SPI.setCS(SS); // SPI.begin();

gfx->begin(); gfx->fillScreen(BLACK); gfx->setCursor(10, 10); gfx->setTextColor(RED); gfx->println("Hello World!");

delay(5000); }

[moononournation]

I have just tested your case, you just need this init code:

Arduino_DataBus *bus = new Arduino_RPiPicoSPI(16 /* DC */, 17 /* CS */, 18 /* SCK */, 19 /* MOSI */, UINT8_MAX /* MISO */, spi0 /* spi */);

[moononournation]

I have a Waveshare Pico LCD 1.3 and have similar declaration:

#include <Arduino_GFX_Library.h>
#define TFT_BL 13
Arduino_DataBus *bus = new Arduino_RPiPicoSPI(8 /* DC */, 9 /* CS */, 10 /* SCK */, 11 /* MOSI */, UINT8_MAX /* MISO */, spi1 /* spi */);
Arduino_GFX *gfx = new Arduino_ST7789(bus, 12 /* RST */, 3 /* rotation */, true /* IPS */, 240, 240, 0, 80);

If your test is positive, I will update the WiKi about it: https://github.com/moononournation/Arduino_GFX/wiki/Dev-Device-Declaration

[moononournation]

@omikron88, any update?