Fix colour/color type and add set_letter for single char msg

hardware/sensehat/README.md

@@ -110,8 +110,11 @@ Format: `R<axis>`
 If `msg.payload` is not recognised as any of the above commands, it is treated
 as a text message to be scrolled across the screen.
 
+If the text is a single character, it will be displayed without scrolling. To
+scroll a single character, append a blank space after it - `"A "`.</p>
+
 The following message properties can be used to customise the appearance:
 
-  - `msg.colour` - the colour of the text, default: `white`
+  - `msg.color` - the colour of the text, default: `white`
   - `msg.background` - the colour of the background, default: `off`
   - `msg.speed` - the scroll speed. A value in the range 1 (slower) to 5 (faster), default: `3`

hardware/sensehat/package.json

@@ -1,6 +1,6 @@
 {
     "name"          : "node-red-node-pi-sense-hat",
-    "version"       : "0.0.4",
+    "version"       : "0.0.5",
     "description"   : "A Node-RED node to interact with a Raspberry Pi Sense HAT",
     "repository" : {
         "type":"git",

hardware/sensehat/sensehat.html

@@ -122,9 +122,11 @@ the horizontal or vertical axis respectively.</p>
 <p><b>Scroll a message</b></p>
 <p>If <code>msg.payload</code> is not recognised as any of the above commands,
 it is treated as a text message to be scrolled across the screen.</p>
+<p>If the text is a single character, it will be displayed without scrolling.
+To scroll a single character, append a blank space after it - <code>"A "</code>.</p>
 <p>The following message properties can be used to customise the appearance:</p>
 <ul>
-    <li><code>msg.colour</code> - the colour of the text, default: <code>white</code></li>
+    <li><code>msg.color</code> - the colour of the text, default: <code>white</code></li>
     <li><code>msg.background</code> - the colour of the background, default: <code>off</code></li>
     <li><code>msg.speed</code> - the scroll speed. A value in the range 1 (slower) to 5 (faster), default: <code>3</code></li>
 </ul>

hardware/sensehat/sensehat.js

@@ -232,7 +232,7 @@ module.exports = function(RED) {
             HAT.close(this,done);
         });
         var handleTextMessage = function(line,msg) {
-            var textCol = colours.getRGB(msg.color);
+            var textCol = colours.getRGB(msg.color||msg.colour);
             var backCol = colours.getRGB(msg.background);
             var speed = null;
             if (!isNaN(msg.speed)) {

hardware/sensehat/sensehat.py

@@ -17,6 +17,7 @@
 #  R[rot] - rotate by rot (0,90,180,270)
 #  P[x,y,R,G,B]+ - set individual pixel(s) to a colour
 #  T[R,G,B[,R,G,B][,S]:]Message - scroll a message (nb: if message contains ':' it must be prefixed with ':')
+#                                 if message is a single char, uses show_letter instead
 #  F[H|V] - flip horizontal|vertical
 #  X[0|1] - high frequency reporting (accel/gyro/orientation/compass) off|on
 #  Y[0|1] - low frequency reporting (temperature/humidity/pressure) off|on
@@ -173,8 +174,11 @@ def process_command(data):
             tcol = (int(c[0]),int(c[1]),int(c[2]))
             bcol = (int(c[3]),int(c[4]),int(c[5]))
             speed = float(c[6])
+      if len(data) > 1:
         scroll = ScrollThread(tcol,bcol,speed,data);
         scroll.start()
+      else:
+        SH.show_letter(data,text_colour=tcol,back_colour=bcol)
     elif data[0] == "F":
       if data[1] == "H":
         SH.flip_h()