Adding yellow warning colour for impending shutter release 2 seconds before firing for intervalometer mode.

Using right button in manual mode to toggle use of NeoPixels.
Halving red NeoPixel colour as it is bright.
Minor code re-arranging and docs.

Author: Kevin J Walters

cpx/cpx-ir-shutter-remote.py

@@ -1,6 +1,5 @@
-### cpx-ir-shutter-remote v1.0
+### cpx-ir-shutter-remote v1.1
 ### Circuit Playground Express (CPX) shutter remote using infrared for Sony Cameras
-### TODO - describe in more detail
 
 ### copy this file to CPX as code.py
 
@@ -26,6 +25,19 @@
 ### OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 ### SOFTWARE.
 
+
+### This uses the Circuit Playground Express with its onboard infrared LED
+### to send the shutter release codes
+
+### If the switch is to the left then the shutter fires when the left button is pressed
+### together with a brief flash of Neopixels.
+### The right button can be used to toggle the use of NeoPixels.
+
+### If the switch is to the right then the CPX functions as an intervalometer
+### with the shutter being fired on a timer after each interval
+### The default interval is thirty seconds and this can be changed
+### by reduced with the left button and increased with the right button
+
 import time
 
 import pulseio
@@ -34,82 +46,103 @@
 from adafruit_circuitplayground import cp
 
 
-debug = 1
-
-def d_print(level, *args, **kwargs):
-    """A simple conditional print for debugging based on global debug level."""
-    if not isinstance(level, int):
-        print(level, *args, **kwargs)
-    elif debug >= level:
-        print(*args, **kwargs)
-
-
-### 40kHz modulation (for Sony)
-### with 20% duty cycle (13107 out of 65535)
+### 40kHz modulation (for Sony) with 20% duty cycle
 CARRIER_IRFREQ_SONY = 40 * 1000
 ir_carrier_pwm = pulseio.PWMOut(board.IR_TX,
                                 frequency=CARRIER_IRFREQ_SONY,
-                                duty_cycle=13107)
+                                duty_cycle=round(20 / 100 * 65535))
 ir_pulseout = pulseio.PulseOut(ir_carrier_pwm)
 
-
 ### Sony timing values (in us) based on the ones in
 ### https://github.com/z3t0/Arduino-IRremote/blob/master/src/ir_Sony.cpp
 ### Disabling the addition of trail value is required to make this work
-### trail=0 does not work
+### trail=0 did not work
 ir_encoder = adafruit_irremote.GenericTransmit(header=[2400, 600],
                                                one=   [1200, 600],
                                                zero=  [600,  600],
                                                trail=None)
 
-SHUTTER_CMD_COLOUR = (16, 0, 0)
+def fire_shutter():
+    """Send infrared code to fire the shutter.
+       This is a code used by Sony cameras."""
+    ir_encoder.transmit(ir_pulseout, [0xB4, 0xB8, 0xF0],
+                        repeat=2, delay=0.005, nbits=20)
+
+
+SHUTTER_CMD_COLOUR = (8, 0, 0)
+IMPENDING_COLOUR = (7, 4, 0)
 BLACK = (0, 0, 0)
 
 S_TO_NS = 1000 * 1000 * 1000
 ADJ_NS = 20 * 1000 * 1000
+IMPENDING_NS = 2 * S_TO_NS
 intervals = [5, 10, 15, 20, 25, 30, 60,
              120, 180, 240, 300, 600, 1800, 3600]
 interval_idx = intervals.index(30)  ### default is 30 seconds
 intervalometer = False
 last_cmd_ns = None
 first_cmd_ns = None
+pixel_indication = True
+impending = False
 
-###encoder.transmit(pulseout, [0x12, 0xB8, 0xF0], nbits=20)  ### start video   
 while True:
-    if cp.switch:  ### switch to left
+    ### CPX switch to left
+    if cp.switch:
         intervalometer = False
         if cp.button_a:  ### left button_a
-            cp.pixels.fill(SHUTTER_CMD_COLOUR)
+            if pixel_indication:
+                cp.pixels.fill(SHUTTER_CMD_COLOUR)
             last_cmd_ns = time.monotonic_ns()
-            ir_encoder.transmit(ir_pulseout, [0xB4, 0xB8, 0xF0],
-                                repeat=3, delay=0.005, nbits=20)  ### shutter
+            fire_shutter()
             if first_cmd_ns is None:
                 first_cmd_ns = last_cmd_ns
             print("Manual", "shutter release at", (last_cmd_ns - first_cmd_ns) / S_TO_NS)
-            cp.pixels.fill(BLACK)
+            if pixel_indication:
+                cp.pixels.fill(BLACK)
             while cp.button_a:
                 pass  ### wait for button release
-    
-    else:  ### switch to right
+
+        elif cp.button_b:
+            pixel_indication = not pixel_indication
+            while cp.button_b:
+                pass  ### wait for button release
+
+    ### CPX switch to right
+    else:
+        if not intervalometer:
+            last_cmd_ns = time.monotonic_ns()
+            intervalometer = True
+
         if cp.button_a and interval_idx > 0:
             interval_idx -= 1
             while cp.button_a:
                 pass  ### wait for button release
+
         elif cp.button_b and interval_idx < len(intervals) - 1:
             interval_idx += 1
             while cp.button_b:
                 pass  ### wait for button release
-        
+
+        ### If enough time has elapsed fire the shutter
+        ### or show the impending colour on NeoPixels
         now_ns = time.monotonic_ns()
-        if (not intervalometer
-            or now_ns - last_cmd_ns >= intervals[interval_idx] * S_TO_NS - ADJ_NS):
-            intervalometer = True
-            
-            cp.pixels.fill(SHUTTER_CMD_COLOUR)
+        interval_ns = intervals[interval_idx] * S_TO_NS
+        if now_ns - last_cmd_ns >= interval_ns - ADJ_NS:
+            if pixel_indication:
+                cp.pixels.fill(SHUTTER_CMD_COLOUR)
             last_cmd_ns = time.monotonic_ns()
-            ir_encoder.transmit(ir_pulseout, [0xB4, 0xB8, 0xF0],
-                                repeat=3, delay=0.005, nbits=20)  ### shutter
+            fire_shutter()
             if first_cmd_ns is None:
                 first_cmd_ns = last_cmd_ns
             print("Timer", "shutter release at", (last_cmd_ns - first_cmd_ns) / S_TO_NS)
+            if pixel_indication:
+                cp.pixels.fill(BLACK)
+            impending = False
+
+        elif (pixel_indication
+              and not impending
+              and now_ns - last_cmd_ns >= interval_ns - IMPENDING_NS):
+            cp.pixels.fill(IMPENDING_COLOUR)
+            time.sleep(0.1)
             cp.pixels.fill(BLACK)
+            impending = True