Electrical Engineer position that I applied has
"Experience with communication and feedback protocols (USB and serial) among and within system components"
as one of requirements. So, here's my preparation for job interview.
Embedded electronics needs interlinking circuits for symbiotic(공생) system.
In order to swap information, there are hundreds of communication protocols.
However, it can be separated into parallel and serial.
Parallel |
Serial |
- multiple bits at same time - require buses, 8,16 or more wires - 8차선 뻥뻥 뚫린 고속도로라고 생각 - more people to destination - fast, straightforward, easy to implement - need many I/O lines |
- one bit at a time - as little as one wire, never more than 4 - 시골의 2차선 도로 생각 - even though slow, serves its purpose and costs - pin적은게 장점 - (ex) USB (Universal Serial Bus) - (ex) Ethernet - (ex) I2C (connect multiple slave devices to one or more master, short distance 2IC on PCB, 2 bidirectional wires, pretty fast ) |
Serial protocols has two different types: Synchronous and Asynchronous
Synchronous |
Asynchronous |
- pairs data line with clock - all device share common clock - straightforward, faster - need least 1 wire for communicating
|
- date transferred without clock signal - minimizing required wires - extra effort for reliable transferring - most common type: serial asynchronous |