2 Replies Latest reply on Nov 6, 2015 9:40 AM by QueTwo

    UPM ST7735 Libraries under Java


      Since the latest updates to MRAA, I've been having great luck programming Java apps to interact with the GPIO, UART and SPI pins with the Intel Edison Breakout Board and the Sparkfun GPIO breakout boards.  Thanks!


      One of my new projects involve the Adafruit 128x128 TFT display which utilizes the ST7735 chipset and communicates via SPI.  I noticed that there is a UPM library available for the ST7735 chip using SPI, but I've not had much luck using it.  I'm able to load the library, but as soon as I instantiate the ST7735 class (ST7735 lcd = new ST7735((short) 45, (short) 48, (short) 47, (short) 46); ) it fails.  There is no error or stacktrace, but there is something in the native code that is causing Java to hang and not continue executing. 


      The Java debugger shows that it dips into the native code and it detaches from there.  Running GDC on the Edison shows nothing (it is running a pthread, which I'm assuming is the so running), but nothing of value.  Nothing is output to the system.err log on the console either.


      The Java code I'm trying to run is : upm/ST7735Sample.java at master · intel-iot-devkit/upm · GitHub , with the pins numbers matching the csLCD, cSD, rs and rst matching my setup.  I'm running the pins through a logic converter to bump the logic voltage up to 3v3. 

      Any help or direction would be appreciated.  Thanks!