HelloWorld.lua

local disp

-- setup SPI and connect display
local function init_spi_display()
   -- Hardware SPI CLK  = GPIO14
   -- Hardware SPI MOSI = GPIO13
   -- Hardware SPI MISO = GPIO12 (not used)
   -- Hardware SPI /CS  = GPIO15 (not used)
   -- CS, D/C, and RES can be assigned freely to available GPIOs
   local cs  = 8 -- GPIO15, pull-down 10k to GND
   local dc  = 4 -- GPIO2
   local res = 0 -- GPIO16
   local bus = 1

   spi.setup(bus, spi.MASTER, spi.CPOL_LOW, spi.CPHA_LOW, 8, 8)
   -- we won't be using the HSPI /CS line, so disable it again
   gpio.mode(8, gpio.INPUT, gpio.PULLUP)

   -- initialize the matching driver for your display
   -- see app/include/ucg_config.h
   --disp = ucg.ili9341_18x240x320_hw_spi(bus, cs, dc, res)
   disp = ucg.st7735_18x128x160_hw_spi(bus, cs, dc, res)
end

do
  init_spi_display()

  disp:begin(ucg.FONT_MODE_TRANSPARENT)
  disp:clearScreen()

  disp:setFont(ucg.font_ncenR12_tr);
  disp:setColor(255, 255, 255);
  disp:setColor(1, 255, 0,0);


  disp:setPrintPos(0, 25)
  disp:print("Hello World!")
end