Problem with rotation on M5 PaperS3

[sok63]

When using FastEPD with the M5PaperS3 panel and setting the rotation to 270 degrees, the top area of the screen shows corrupted graphics.
It looks like a buffering or address mapping issue specific to 270° rotation, as 0°/90°/180° do not show this problem on the same hardware and sketch.​

Sketch to reproduce problem:

#include <FastEPD.h>

FASTEPD epd;

void setup()
{
    Serial.begin(115200);
    delay(1000);

    epd.initPanel(BB_PANEL_M5PAPERS3);
    epd.einkPower(1);
    delay(100);

    epd.setFont(FONT_8x8);
    epd.setTextColor(BBEP_BLACK, BBEP_WHITE);

    epd.setRotation(270);
    epd.fillScreen(BBEP_WHITE);
    epd.drawString("270 deg", 10, 10);
    
    epd.fullUpdate();
}

void loop()
{
    delay(1000);
}

[bitbank2]

A few things:

• You don't need to explicitly turn on the Eink power; your first try at updating it will turn it it.
• You definitely don't need to add any specific delays to the code. All timing and testing of voltages is done internally.

I did some testing and everything is working as it should. I have made some updates since the latest point release. Clone the latest repo and try again.

Here's a photo of the compressed_images example with 8x8 rotated text thrown in.