Add libraries, picocalc notes.

libraries/TFT_eSPI/examples/Test and diagnostics/TFT_ReadWrite_Test/TFT_ReadWrite_Test.ino

@@ -0,0 +1,37 @@
+// Walking 1 write and read pixel test
+
+#include <TFT_eSPI.h>
+#include <SPI.h>
+
+#define TDELAY 500
+
+TFT_eSPI tft = TFT_eSPI(); 
+
+void setup() {
+  Serial.begin(115200);
+
+  tft.init();
+  tft.fillScreen(0xF81F);
+}
+
+void loop() {
+  static uint32_t wr = 1;
+  static uint32_t rd = 0xFFFFFFFF;
+
+  delay(TDELAY);
+
+  tft.drawPixel(30,30,wr);
+  Serial.print(" Pixel value written = ");Serial.println(wr,HEX);
+  
+  rd = tft.readPixel(30,30);
+                Serial.print(" Pixel value read    = ");Serial.println(rd,HEX);
+
+  if (rd!=wr) {
+    Serial.println(" ERROR                 ^^^^");
+    //while(1) yield();
+  }
+  else Serial.println(" PASS ");
+  // Walking 1 test
+  wr = wr<<1;
+  if (wr >= 0x10000) wr = 1;
+}