unit is shown in Figure H with labels.
Rather than use 4 wall warts for camera
power plus another for the circuit, I supply
them all with a larger supply rated at 2A
at 12V DC. To do this, cut the plugs off the
included adapters and wire them in parallel to
the DC power jack. Then wire another parallel
pair of leads from the the DC power jack to
(+) and (–) in one corner of the board. The
power plugs can plug into the camera cables
inside or outside the box (Figure I). G
3. PROGRAM, CONNECT,
Download the project software for the Picaxe
or PIC microcontroller at makeprojects.com/
v/30, and follow the directions there if you
haven’t programmed the microcontroller
before. The 2 versions of the software are
almost identical. The main differences are in
how variables and pins are named.
With the PIC16F684, which you program via
4-pin ICSP (in-circuit serial programming),
you must configure your programmer so that
pin 4 (MCLR) is set to an input pin, and you
must have the switch connected to that pin
(UseCamera2) set to Off. Compile and upload
the code to the microcontroller, plug the chips
into the PCB, and you’re ready to connect.
Make sure the EasyCap unit is switched
to NTSC video, not PAL. Plug it into the
computer’s USB port, install the driver from
the included CD when prompted, and continue past any warning that the driver hasn’t
passed Windows Logo Testing.
Download and install Yawcam (yawcam.
com), then launch it and select Settings →
Detect WebCam. Syntek STK1150 should
appear in the list of devices. Select Settings →
Device (Syntek STK1150) → Device Properties
and specify NTSC/M and Composite Video
From the main menu, select Settings →
Edit Settings, then choose Startup and Start
Stream Output. Click on Stream — the default
port number should be 8081. I changed this
to 8888 to accommodate other devices on
my network, but you can leave it at 8081.
Select File → Enable Stream-output. If your
computer’s firewall warns you that it’s blocking a port, select Unblock. To see the webcam
image, enter your local IPv4 address followed
by “:8081” into a web browser (Figure K).
You can determine this address by entering
ipconfig in the Windows command window
(cmd.exe) and looking for the IP Address
value (Figure L). You should see the Yawcam
server screen with your live webcam image
48 Make: makezine.com/30