Add example with internal filesystem write.

Author: tdicola

examples/snapshot_internal.py

@@ -0,0 +1,77 @@
+# VC0706 image capture to internal storage demo.
+# You must wire up the VC0706 to the board's serial port, and enable writes
+# to the internal filesystem by following this page to edit boot.py:
+#   https://learn.adafruit.com/cpu-temperature-logging-with-circuit-python/writing-to-the-filesystem
+import board
+import busio
+import digitalio
+import time
+
+import adafruit_vc0706
+
+
+# Configuration:
+RX_PIN     = board.RX     # RX pin of board, connected to VC0706 TX
+TX_PIN     = board.TX     # TX pin of board, connected to VC0706 RX
+IMAGE_FILE = '/image.jpg' # Full path to file name to save captured image.
+                          # Will overwrite!
+
+# Setup SPI bus (hardware SPI).
+spi = busio.SPI(board.SCK, MOSI=board.MOSI, MISO=board.MISO)
+
+# Setup VC0706.
+vc0706 = adafruit_vc0706.VC0706(RX_PIN, TX_PIN)
+
+# Print the version string from the camera.
+print('VC0706 version:')
+print(vc0706.version)
+
+# Set the image size.
+vc0706.image_size = adafruit_vc0706.VC0706_640x480 # Or set VC0706_320x240 or
+                                                   # VC0706_160x120
+# Note you can also read the property and compare against those values to
+# see the current size:
+size = vc0706.image_size
+if size == adafruit_vc0706.VC0706_640x480:
+    print('Using 640x480 size image.')
+elif size == adafruit_vc0706.VC0706_320x240:
+    print('Using 320x240 size image.')
+elif size == adafruit_vc0706.VC0706_160x120:
+    print('Using 160x120 size image.')
+
+# Take a picture.
+print('Taking a picture in 3 seconds...')
+time.sleep(3)
+print('SNAP!')
+if not vc0706.take_picture():
+    raise RuntimeError('Failed to take picture!')
+
+# Print size of picture in bytes.
+frame_length = vc0706.frame_length
+print('Picture size (bytes): {}'.format(frame_length))
+
+# Open a file for writing (overwriting it if necessary).
+# This will write 50 bytes at a time using a small buffer.
+# You MUST keep the buffer size under 100!
+print('Writing image: {}'.format(IMAGE_FILE), end='')
+with open(IMAGE_FILE, 'wb') as outfile:
+    wcount = 0
+    while frame_length > 0:
+        # Compute how much data is left to read as the lesser of remaining bytes
+        # or the copy buffer size (32 bytes at a time).  Buffer size MUST be
+        # a multiple of 4 and under 100.  Stick with 32!
+        to_read = min(frame_length, 32)
+        copy_buffer = bytearray(to_read)
+        # Read picture data into the copy buffer.
+        if vc0706.read_picture_into(copy_buffer) == 0:
+            raise RuntimeError('Failed to read picture frame data!')
+        # Write the data to SD card file and decrement remaining bytes.
+        outfile.write(copy_buffer)
+        frame_length -= 32
+        # Print a dot every 2k bytes to show progress.
+        wcount += 1
+        if wcount >= 64:
+            print('.', end='')
+            wcount = 0
+print()
+print('Finished!')