fix: lower expectations for ATmega2560

docs/API.md

@@ -1576,7 +1576,8 @@ The width of the string.
 ___
 ### `overwrite()`
 
-**Not supported on ATmega328P (Uno / Nano)** 
+**ATmega328P (Uno / Nano): not supported**<br />
+**ATmega2560: disabled for some displays** 
 
 Execute drawing commands outside a `DRAW` loop, drawing on-top of the existing screen data.
 

docs/README.md

@@ -175,11 +175,14 @@ It takes a bit longer, but without paging, Arduino Uno R3 wouldn't stand a chanc
 
 ![paging graphic](/docs/paging_graphic.png)
 
-If you have a more powerful board (ESP, Mega), the library won't waste time paging. Your image will be calculated once, and once only.
+If you have a more powerful board (ESP32  ESP8266), the library won't waste time paging. Your image will be calculated once, and once only.
 
 If you board has the resources, paging is disabled automatically.
 If, for any reason, you should want to turn it back on, you can set a `page_height` in your [constructor](/docs/API.md#display-constructors).
 
+**ATmega2560 is marginal.** <br /> Paging is used for some displays. On other displays, a large amount of RAM is occupied.
+ DEPG0290BNS800 uses **60% of  ATmega2560's RAM**. If this in unacceptable, enable paging by setting a `page_height` in your [constructor](/docs/API.md#display-constructors).
+
 ## Drawing stuff
 
 ```c++

examples/overwrite/overwrite.ino

@@ -1,6 +1,7 @@
 #include "heltec-eink-modules.h"
 
-// -- Example will not run on Arduino Uno / Nano --
+// -- Example will not run on Arduino Uno / Nano
+// -- Example *may* run on Arduino Mega
 
 // Find your wiring  -  https://github.com/todd-herbert/heltec-eink-modules#wiring
 // ----------------

examples/xbitmap_multicolor/xbitmap_multicolor.ino

@@ -32,7 +32,7 @@
 // DEMO: Multicolor XBitmap Images
 // =================================
     // XBitmap is an old image file format from the early days of the internet
-    // It was very inefficient as the imagedata was stored more or less as human readable C code
+    // It was very inefficient as the image data was stored more or less as human readable C code
     // This, however, serves our purposes very well. As such, Adafruit have chosen to add support for XBM images
     // These can be easily created with the free GIMP software.
 
@@ -53,7 +53,7 @@ PANEL_CLASS display(DC_PIN, CS_PIN, BUSY_PIN);
 void setup() {
     display.setRotation(PINS_LEFT);   // Don't forget to set the orientation, so your image fits how you intended
 
-    while( display.calculating() ) {
+    DRAW (display) {
         // Draw each image to its destination color
         display.drawXBitmap(0, 0, apples_black_bits, apples_black_width, apples_black_height, BLACK);
         display.drawXBitmap(0, 0, apples_red_bits, apples_red_width, apples_red_height, RED);

src/Displays/QYEG0213RWS800/QYEG0213RWS800.h

@@ -20,13 +20,13 @@ class QYEG0213RWS800 : public BaseDisplay {
     public:
 
         // UNO-style constructor
-        QYEG0213RWS800(  uint8_t pin_dc, uint8_t pin_cs, uint8_t pin_busy, uint16_t page_height = DEFAULT_PAGE_HEIGHT)
+        QYEG0213RWS800(  uint8_t pin_dc, uint8_t pin_cs, uint8_t pin_busy, uint16_t page_height = 50)   // Enable paging, 3 Colors takes too much RAM
             : BaseDisplay ( pin_dc, pin_cs, pin_busy, DEFAULT_SDI, DEFAULT_CLK, page_height) 
                 { init(); }
 
         // Full pinout constructor
         #if CAN_SPECIFY_SPI_PINS
-            QYEG0213RWS800(  uint8_t pin_dc, uint8_t pin_cs, uint8_t pin_busy, uint8_t pin_sdi, uint8_t pin_clk, uint16_t page_height = DEFAULT_PAGE_HEIGHT)
+            QYEG0213RWS800(  uint8_t pin_dc, uint8_t pin_cs, uint8_t pin_busy, uint8_t pin_sdi, uint8_t pin_clk, uint16_t page_height = 50) // Enable paging, 3 Colors takes too much RAM
                 : BaseDisplay ( pin_dc, pin_cs, pin_busy, pin_sdi, pin_clk, page_height)
                     { init(); }