Wired Communication Systems (Week 4)

Question 1

Synchronous Serial

Answer 1

A way for two devices to send data using a clock signal to keep them in sync

Question 2

I2C (Inter-Integrated Circuit)

Answer 2

A simple way for a microcontroller to talk to multiple sensors or devices just using two wires. (it can sendand receive, but only one device can talk at a time)

Can connect to one or more peripherals (a device that connects to a microcontroller).
Each peripheral listens for their own address to determine if data is for them.
Two wires:
(1) SDA =Data
(2) SCL =clock

Question 3

SPI (Serial Peripheral Interface)

Answer 3

Super fast way for devices to send and receive data at the same time using four wires.

Question 4

Asynchronous Serial

Answer 4

Its a way for devices to send data without needing a shared clock.

This reduces the number of wires.

Connected devices have to follow a set of rules to ensure reliable data transfer:
-Data bits/chunk
-Synchronization bits
-parity bits

The rate of the data transfer is determined by the baud rate

Question 5

Data bit/chunk

Answer 5

Contains information to be transferred.

Question 6

Synchronization bits

Answer 6

They are special bits that are added to each data chunk to show where the data starts and ends.

start bit: always 1 bit

end bit: usually 1 bit sometimes 2

Question 7

Parity Bits

Answer 7

Its a tiny error checking tool. It helps catch mistakes if a bit got messed up during transition

They count the number of 1s in the message.

if they want it to be even and there is an even number of 1s then –> Parity bit =0

if they want even and its odd then parity bit =1

if you want odd and its odd =0
if you want odd and its even =1

Question 8

Baud Rate

Answer 8

The baud rate refers to how fast data is sent (measured in bits per second). Both the sending and receiving devices must use the same baud rate so that the data is not misread.

When sending bits, the transmitter holds the line at a high or low voltage (representing 1 or 0).The baud rate determines how long it holds each bit for. The receiver checks the line at that timing — based on the baud rate — to correctly read the bits.
That’s why both devices need to be synchronized to the same baud rate.

Line= the wire or electrical connection that caries the signal between the devices

Question 9

Asynchronous Serial Wiring

Answer 9

You need two wires (or pins)

TX= transmitter (Sends data)
RX= Receiver (Recives data)

The RX from one device connects to the TX of the other device, and vice versa
The ground is shared

Can operate at half or full duplex (half- devices take turns communicating, full- communicate at the same time) or can be simplex (one way communication)

Question 10

UART

Answer 10

Universal asynchronous Reciver/transmitter that implements serial communicaation. It operates between parallel and serial interfaces.

serial - bits sent one at a time, fewer wires, slower
parrallel- multiple bits sent at the same time (8 bits need 8 wires because its all at once), multiple data lines needed, faster

most UARTs place data into a buffer
-Holds data until it is processed
-buffered data is release on a FIFO basis