move circuitpython to subdir, add arduino examples

Author: FoamyGuy

PiCowbell_HSTX_DVI_Examples/arduino_rp2040_hstx_dvi_cowbell/.pico_rp2040.test.only

@@ -0,0 +1,25 @@
+// 16-bit Adafruit_GFX-compatible framebuffer for RP2350 HSTX
+
+#include <Adafruit_dvhstx.h>
+
+// initialize display with HSTX DVI CowBell pinout
+DVHSTX16 display({14, 12, 18, 16}, DVHSTX_RESOLUTION_320x240);
+
+void setup() {
+  Serial.begin(115200);
+  // while(!Serial);
+  if (!display.begin()) { // Blink LED if insufficient RAM
+    pinMode(LED_BUILTIN, OUTPUT);
+    for (;;)
+      digitalWrite(LED_BUILTIN, (millis() / 500) & 1);
+  }
+  Serial.println("display initialized");
+}
+
+void loop() {
+  // Draw random lines
+  display.drawLine(random(display.width()), random(display.height()),
+                   random(display.width()), random(display.height()),
+                   random(65536));
+  sleep_ms(1);
+}