Specifications
38
Figure 29 - Serial Connection on LCD
Permission Pending
All of the settings will be stored on the LCD display in the EEPROM chip. This will store
the configuration of the display as well as its timeout feature. We will also store in that
chip how we want the characters to be displayed. We will be using a 20 character wide
format which will display the characters on the screen a little smaller than we wanted to
but we will try to condense the material to show on a 16 character wide display to make
it more readable for the users. To turn on and off the display we will be using pin 15 to
turn off and on the display when it is not in use. This LCD chip needs 5 volts to work
There are thousands of different LCD screens on the market we chose this one
because it has a very low power consumption. It also has the ability to turn on and off
the backlight. Price was also an option that we had to consider. We needed a display
that was cheap as well meet all the demanding requirements that we need to make all
of these requirements work. There is also a communication protocol that is easy to
understand and is compatible with many other protocols that are on the market. The
reason we didn‟t choose a graphical LCD was because we are trying to optimize power
and cost and using a graphical display will cost more money as well as consume more
power as the one we are using.
The operating temperature of this LCD display is very important because the solar
panels will draw heat which will cause the box temperature to get somewhere in the
range of 80
o
F to 90
o
F. Due to this issue we will need to choose a LCD that will have a
high operating temperature so that it can deal with the heat. Also location will play a
very important role in this because there will be places on the box where heat will be
high and places that it will be lower. The electrical components and chips will be placed
lower in the box due to the fact that heat rises and the bottom will be cooler than the top
because of this physical property of heat.
4.1.9 Microcontrollers
Microcontrollers, which are small computers on integrated chips, are commonly used in
embedded applications. They include a processor core, memory, and input/output
peripherals, and are usually used to accomplish dedicated and/or specific tasks.
Examples of devices that use microcontrollers include automobile engine control