Team 15

PSSCs An ability to measure chlorine concentration, water temperature, and pH with an accuracy of ±5% An ability to dispense measured amounts of regulatory chemicals into a pool. An ability to log chlorine concentration, water temperature, and pH data collected over a 30-day period in nonvolatile memory. An ability to display data logs and configure operating parameters, both locally and remotely. An ability to detect potentially hazardous chemical concentration levels and sound a local alarm in response and send an alert.

Controller Design Constraints Controller: Ethernet (and sufficient RAM/Flash) to implement the web server. Enough memory to save the 30-day log of measurements. ATDs to sample sensor data. SPI for LCD display. Enough I/O pins to control the 7 pumps and 3 sensors. SCI for debugging/updating. PWM to implement an alarm for dangerous chemical levels.

Power Design Constraints There will be 8 pumps and a electric heating element. Power should support the hefty load of the pumps and heating element. 3.3V is required for the controller. 5V is required for serial shift register.

Other Design Constraints Need to isolate (optically) pins from pumps due to the high current draw. Water resistant, design for splashes and waterproof our circuits. Need of an amplifier to make the alarm effective.

Component Selection MC9S12NE64