How do I send part of an ArrayBuffer to SPI

Hmm, not sure any more.

Tested a lcd spi ILI9341 with 320x240 pixel, interval 0.1sec and it's not as slow as in video post #9.

https://youtu.be/OHwegdm01xw

        g.setColor(0xffff).setFont("Vector", 40).clearRect(120,100,200,140).drawString(times, 120, 100, true);
        g.setColor(0xffff).setFont("6x8", 4).drawString(times, 120, 160, true);