Specifications
120
Main Microcontroller
Secondary Microcontroller
Supply Voltage: 3 – 3.6V
Supply Voltage: 1.8 – 3.6V
Up to 40 MIPS
4 Kbytes program memory
Two 40 – bit accumulators
1 SPI port
32/16 and 16/16 divide operations
1 I
2
C port
16 x 16 fractional/integer multiply
operations
1 UART port
256 Kbytes Flash memory
C Language compatible
30 Kbytes RAM
18 programmable I/O pins
85 programmable I/O pins
10 – Bit A/D converter
2 SPI ports
3 timers
2 I
2
C ports
512 bytes RAM
2 UART ports
Table 35 Final microcontroller specs
The main microcontroller that is used in the design requires a supply voltage of 3
– 3.6 V in order to be powered on. It has 85 programmable I/O pins that will be
used as outputs to control relays. It has 2 SPI ports, 2 I
2
C ports, and 2 UART
ports that will be used for interfacing with other components in the main control
units. The 256k bytes of on-board flash memory will be used to store the
programming for the decision making logic and the 512 bytes RAM will run the
program. All programming for the main microcontroller will be done using the C
language.
The secondary microcontroller that is used in the design requires a supply
voltage of 1.8 – 3.6V in order to be powered on. It has 1 SPI port and 1 I
2
C port
that will be used to communicate with the sensor and the ZigBee chip. The
programming will be stored in the 4K bytes program memory and the 512 bytes
RAM will run the program. All programming for the secondary microcontroller will
be done using the C language.
5.7.2 Final Requirements
The sponsor for our project, AC3 Development Group, LLC provided the
requirements for our project. The high level requirements of the system are as
follows. The system is required to sense temperature and relative humidity from
inside and outside a building (residential or commercial), read the settings
determined by the user (inputted via LCD touch screen interface), and make an