Blackmagicdesign Design 3G-SDI Arduino Shield, Инструкция по установке и эксплуатации, Страница: 14 / 253

14 Communicating with your Arduino Shield
Attaching Shield Components
If you want to build your own hardware controller, you can create a new shield with buttons,
knobs and a joystick for more tactile, hands on control. Simply mount the custom shield to your
Blackmagic 3G-SDI Arduino Shield by plugging it into your shield’s header slots. There is no
limit to the types of controllers you can build. You can even replace the circuitry in an old CCU
with your own custom Arduino solution for an industry standard camera control unit.
You can create your own hardware controller and
plug it into your Blackmagic 3G-SDI Arduino Shield for
more interactive and refined control.
Communicating with your Arduino Shield
You can communicate with your Arduino Shield via I
2
C or Serial. We recommend I
2
C because of
the low pin count and it frees up the serial monitor. This also allows you to use more I
2
C devices
with the shield.
High Level Overview
The library provides two core objects, BMD_SDITallyControl and BMD_SDICameraControl,
which can be used to interface with the shield’s tally and camera control functionalities. Either
or both of these objects can be created in your sketch to issue camera control commands, or
read and write tally data respectively. These objects exist in several variants, one for each of
the physical I
2
C or Serial communication busses the shield supports.
I
2
C Interface
To use the I
2
C interface to the shield:
// NOTE: Must match address set in the setup utility software
const int
shieldAddress = 0x6E;
BMD _ SDICameraControl _ I2C sdiCameraControl(shieldAddress);
BMD _ SDITallyControl _ I2C sdiTallyControl(shieldAddress);