Sequence controllers

1. Memory is persistent data that is stored in an array of data units
2. Each data unit stores a number of bits of data that can be handled through a set of pins A₀ called a data bus
3. Each data unit has a unique memory address that is chosen through a set of pins called a memory bus
4. Data can be read or written according to a Read/Write pin: when reading, the data from the address referenced by the address bus is outputted through the data buss; when writing, the data from the data bus is stored into the address referenced by the address bus
5. By connecting a counter to the address bus, a memory IC can be made to output a sequence of preloaded data, and can be made to reset when reaching a certain state using logic

Software-based controllers

1. A microcontroller is a multipurpose chip whose function is programmed into it
2. It contains its own program memory, data storage memory, input/output ports and a clock oscillator
3. This allows it to take signals from input sensors and send signals to output devices

4. A program is a sequence of instructions, which can be represented using a flowchart, which typically contains the following nodes:

   1. Start: a single start node is used to indicate the beginning of every flowchart
   2. Stop: used to end program; there can be any number of stop nodes, even none
   3. Process: used for calculations or delays
   4. Decision: branches according to whether the conditional in the node is true or false
   5. Output: sends data to an output pin