Pixl.js: Add Pixl.setLCDPower to allow the LCD to be powered off, mor…

…e than halving power consumption
espruino · Aug 30, 2018 · 87f2ce3 · 87f2ce3
1 parent 603add0
commit 87f2ce3
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Showing 3 changed files with 32 additions and 1 deletion.
diff --git a/ChangeLog b/ChangeLog
@@ -68,6 +68,7 @@
             Automatically shut down UART if both pin states are changed
             Fix `setDeviceClockCmd: Unknown Device` when using `LoopbackB.setConsole()` on WiFi board
             Fix non-UART serial regressions (after software serial additions)
+            Pixl.js: Add Pixl.setLCDPower to allow the LCD to be powered off, more than halving power consumption
 
      1v99 : Increase jslMatch error buffer size to handle "UNFINISHED TEMPLATE LITERAL" string (#1426)
             nRF5x: Make FlashWrite cope with flash writes > 4k

diff --git a/libs/pixljs/jswrap_pixljs.c b/libs/pixljs/jswrap_pixljs.c
@@ -293,6 +293,33 @@ void jswrap_pixljs_setContrast(JsVarFloat c) {
   jshPinSetValue(LCD_SPI_CS,1);
 }
 
+/*JSON{
+    "type" : "staticmethod",
+    "class" : "Pixl",
+    "name" : "setLCDPower",
+    "generate" : "jswrap_pixljs_setLCDPower",
+    "params" : [
+      ["isOn","bool","True if the LCD should be on, false if not"]
+    ]
+}
+This function can be used to turn Pixl.js's LCD off or on.
+
+* With the LCD off, Pixl.js draws around 0.1mA
+* With the LCD on, Pixl.js draws around 0.25mA
+*/
+void jswrap_pixljs_setLCDPower(bool isOn) {
+  jshPinSetValue(LCD_SPI_CS,0);
+  jshPinSetValue(LCD_SPI_DC,0);
+  if (isOn) {
+    lcd_wr(0xA4); // cancel pixel on
+    lcd_wr(0xAF); // display on
+  } else {
+    lcd_wr(0xAE); // display off
+    lcd_wr(0xA5); // all pixels on
+  }
+  jshPinSetValue(LCD_SPI_CS,1);
+}
+
 /*JSON{
     "type" : "staticmethod",
     "class" : "Pixl",
@@ -471,7 +498,8 @@ void jswrap_pixljs_init() {
   };
 
   // Create 'flip' fn
-  JsVar *fn = jsvNewNativeFunction((void (*)(void))lcd_flip, JSWAT_VOID|JSWAT_THIS_ARG|(JSWAT_BOOL << (JSWAT_BITS*1)));
+  JsVar *fn;
+  fn = jsvNewNativeFunction((void (*)(void))lcd_flip, JSWAT_VOID|JSWAT_THIS_ARG|(JSWAT_BOOL << (JSWAT_BITS*1)));
   jsvObjectSetChildAndUnLock(graphics,"flip",fn);
   // LCD init 2
   jshDelayMicroseconds(10000);
@@ -486,6 +514,7 @@ void jswrap_pixljs_init() {
        35,     // actual contrast (0..63)
        0x25,   // regulation resistor ratio (0..7)
        0x2F,   // control power circuits - last 3 bits = VB/VR/VF
+       0xF8, 1, // Set boost level to 5x - draws maybe 0.04mA more, but much better blacks
        0xA0,   // start at column 128
        0xAF    // disp on
   };

diff --git a/libs/pixljs/jswrap_pixljs.h b/libs/pixljs/jswrap_pixljs.h
@@ -16,6 +16,7 @@
 JsVar *jswrap_pixljs_menu(JsVar *menu);
 void jswrap_pixljs_lcdw(JsVarInt c);
 void jswrap_pixljs_setContrast(JsVarFloat c);
+void jswrap_pixljs_setLCDPower(bool isOn);
 
 void jswrap_pixljs_init();
 void jswrap_pixljs_kill();