Source code for adafruit_vc0706

# SPDX-FileCopyrightText: 2017 Tony DiCola  for Adafruit Industries
#
# SPDX-License-Identifier: MIT

"""
`adafruit_vc0706`
====================================================

VC0706 serial TTL camera module.  Allows basic image capture and download of
image data from the camera over a serial connection.  See examples for demo
of saving image to a SD card (must be wired up separately).

* Author(s): Tony DiCola

Implementation Notes
--------------------

**Hardware:**

* Adafruit `TTL Serial JPEG Camera with NTSC Video
  <https://www.adafruit.com/product/397>`_ (Product ID: 397)

**Software and Dependencies:**

* Adafruit CircuitPython firmware for the ESP8622 and M0-based boards:
  https://github.com/adafruit/circuitpython/releases
"""
from micropython import const

__version__ = "0.0.0-auto.0"
__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_VC0706.git"

_SERIAL = const(0x00)
_RESET = const(0x26)
_GEN_VERSION = const(0x11)
_SET_PORT = const(0x24)
_READ_FBUF = const(0x32)
_GET_FBUF_LEN = const(0x34)
_FBUF_CTRL = const(0x36)
_DOWNSIZE_CTRL = const(0x54)
_DOWNSIZE_STATUS = const(0x55)
_READ_DATA = const(0x30)
_WRITE_DATA = const(0x31)
_COMM_MOTION_CTRL = const(0x37)
_COMM_MOTION_STATUS = const(0x38)
_COMM_MOTION_DETECTED = const(0x39)
_MOTION_CTRL = const(0x42)
_MOTION_STATUS = const(0x43)
_TVOUT_CTRL = const(0x44)
_OSD_ADD_CHAR = const(0x45)

_STOPCURRENTFRAME = const(0x0)
_STOPNEXTFRAME = const(0x1)
_RESUMEFRAME = const(0x3)
_STEPFRAME = const(0x2)

# pylint doesn't like the lowercase x but it makes it more readable.
# pylint: disable=invalid-name
IMAGE_SIZE_640x480 = const(0x00)
IMAGE_SIZE_320x240 = const(0x11)
IMAGE_SIZE_160x120 = const(0x22)
# pylint: enable=invalid-name
_BAUDRATE_9600 = const(0xAEC8)
_BAUDRATE_19200 = const(0x56E4)
_BAUDRATE_38400 = const(0x2AF2)
_BAUDRATE_57600 = const(0x1C1C)
_BAUDRATE_115200 = const(0x0DA6)

_MOTIONCONTROL = const(0x0)
_UARTMOTION = const(0x01)
_ACTIVATEMOTION = const(0x01)

__SET_ZOOM = const(0x52)
__GET_ZOOM = const(0x53)

_CAMERA_DELAY = const(10)


[docs]class VC0706: """Driver for VC0706 serial TTL camera module. :param ~busio.UART uart: uart serial or compatible interface :param int buffer_size: Receive buffer size """ def __init__(self, uart, *, buffer_size=100): self._uart = uart self._buffer = bytearray(buffer_size) self._frame_ptr = 0 self._command_header = bytearray(3) for _ in range(2): # 2 retries to reset then check resetted baudrate for baud in (9600, 19200, 38400, 57600, 115200): self._uart.baudrate = baud if self._run_command(_RESET, b"\x00", 5): break else: # for:else rocks! http://book.pythontips.com/en/latest/for_-_else.html raise RuntimeError("Failed to get response from VC0706, check wiring!") @property def version(self): """Return camera version byte string.""" # Clear buffer to ensure the end of a string can be found. self._send_command(_GEN_VERSION, b"\x01") readlen = self._read_response(self._buffer, len(self._buffer)) return str(self._buffer[:readlen], "ascii") @property def baudrate(self): """Return the currently configured baud rate.""" return self._uart.baudrate @baudrate.setter def baudrate(self, baud): """Set the baudrate to 9600, 19200, 38400, 57600, or 115200. """ divider = None if baud == 9600: divider = _BAUDRATE_9600 elif baud == 19200: divider = _BAUDRATE_19200 elif baud == 38400: divider = _BAUDRATE_38400 elif baud == 57600: divider = _BAUDRATE_57600 elif baud == 115200: divider = _BAUDRATE_115200 else: raise ValueError("Unsupported baud rate") args = [0x03, 0x01, (divider >> 8) & 0xFF, divider & 0xFF] self._run_command(_SET_PORT, bytes(args), 7) self._uart.baudrate = baud @property def image_size(self): """Get the current image size, will return a value of IMAGE_SIZE_640x480, IMAGE_SIZE_320x240, or IMAGE_SIZE_160x120. """ if not self._run_command(_READ_DATA, b"\0x04\x04\x01\x00\x19", 6): raise RuntimeError("Failed to read image size!") return self._buffer[5] @image_size.setter def image_size(self, size): """Set the image size to a value of IMAGE_SIZE_640x480, IMAGE_SIZE_320x240, or IMAGE_SIZE_160x120. """ if size not in (IMAGE_SIZE_640x480, IMAGE_SIZE_320x240, IMAGE_SIZE_160x120): raise ValueError( "Size must be one of IMAGE_SIZE_640x480, IMAGE_SIZE_320x240, or " "IMAGE_SIZE_160x120!" ) return self._run_command( _WRITE_DATA, bytes([0x05, 0x04, 0x01, 0x00, 0x19, size & 0xFF]), 5 ) @property def frame_length(self): """Return the length in bytes of the currently capture frame/picture.""" if not self._run_command(_GET_FBUF_LEN, b"\x01\x00", 9): return 0 frame_length = self._buffer[5] frame_length <<= 8 frame_length |= self._buffer[6] frame_length <<= 8 frame_length |= self._buffer[7] frame_length <<= 8 frame_length |= self._buffer[8] return frame_length
[docs] def take_picture(self): """Tell the camera to take a picture. Returns True if successful.""" self._frame_ptr = 0 return self._run_command(_FBUF_CTRL, bytes([0x1, _STOPCURRENTFRAME]), 5)
[docs] def resume_video(self): """Tell the camera to resume being a camera after the video has stopped (Such as what happens when a picture is taken). """ return self._run_command(_FBUF_CTRL, bytes([0x1, _RESUMEFRAME]), 5)
[docs] def read_picture_into(self, buf): """Read the next bytes of frame/picture data into the provided buffer. Returns the number of bytes written to the buffer (might be less than the size of the buffer). Buffer MUST be a multiple of 4 and 100 or less. Suggested buffer size is 32. """ n = len(buf) if n > 256 or n > (len(self._buffer) - 5): raise ValueError("Buffer is too large!") if n % 4 != 0: raise ValueError("Buffer must be a multiple of 4! Try 32.") args = bytes( [ 0x0C, 0x0, 0x0A, 0, 0, (self._frame_ptr >> 8) & 0xFF, self._frame_ptr & 0xFF, 0, 0, 0, n & 0xFF, (_CAMERA_DELAY >> 8) & 0xFF, _CAMERA_DELAY & 0xFF, ] ) if not self._run_command(_READ_FBUF, args, 5, flush=False): return 0 if self._read_response(self._buffer, n + 5) == 0: return 0 self._frame_ptr += n for i in range(n): buf[i] = self._buffer[i] return n
def _run_command(self, cmd, args, resplen, flush=True): if flush: self._read_response(self._buffer, len(self._buffer)) self._send_command(cmd, args) if self._read_response(self._buffer, resplen) != resplen: return False if not self._verify_response(cmd): return False return True def _read_response(self, result, numbytes): return self._uart.readinto(memoryview(result)[0:numbytes]) def _verify_response(self, cmd): return ( self._buffer[0] == 0x76 and self._buffer[1] == _SERIAL and self._buffer[2] == cmd & 0xFF and self._buffer[3] == 0x00 ) def _send_command(self, cmd, args=None): self._command_header[0] = 0x56 self._command_header[1] = _SERIAL self._command_header[2] = cmd & 0xFF self._uart.write(self._command_header) if args: self._uart.write(args)