[Solved] You wrote this code to read from a serial device but get no output: import serial ser = serial.Serial('/dev/ttyS0', 115200) data = ser.read(5) print(data) What is the likely problem? | Raspberry Pi

Raspberry Pi - Serial UART Communication

You wrote this code to read from a serial device but get no output:

import serial
ser = serial.Serial('/dev/ttyS0', 115200)
data = ser.read(5)
print(data)

What is the likely problem?

AThe serial port '/dev/ttyS0' is not valid on Raspberry Pi

BThe read() function requires a string argument, not an integer

Cprint() cannot display bytes

DThe baud rate 115200 does not match the device speed

Step-by-Step Solution

Solution:

Step 1: Check baud rate importance
Serial communication requires matching baud rates on both ends; mismatch causes no data or garbage.
Step 2: Validate other code parts
read() accepts integer bytes count, '/dev/ttyS0' is valid, and print() can display bytes, so these are not issues.
Final Answer:
The baud rate 115200 does not match the device speed -> Option D
Quick Check:
Baud rate mismatch = no data received [OK]

Quick Trick: Match baud rates exactly to get data [OK]

Common Mistakes:

MISTAKES

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