fall detection medical alert
Our design for a functional keypad was the usage of an alternation of ports between inputs and outputs which is done by using the TRIS function. We started off by setting the first four ports of PORTB as the inputs and the latter four ports as the outputs. The first four ports are connected to the columns meanwhile the last four are connected to the rows. Moreover, as a justification for this reasoning is the fact
that it is required to scan the columns for the pressed key and then scan the rows and the results will be decoded in a decoder telling us which button of the keypad was pressed. The main functionality of the keypad as mentioned earlier is to set the code. The alarm can be armed and disarmed with a standard four digit user code in our case. The master code is a step above a regular user code. It is used to unlock the system, as well as programming or erasing a regular user code. Theoretically it can also be used to bypass some sensors. The default password set during the design, which is also the installation code, is 1234. Most alarm companies use the same installer
code for all of their installations, and the vast majority will never give their installer code to a customer, for obvious reasons.