[Solved] What will be the output of this code snippet?import serial ser = serial.Serial('/dev/ttyS0', baudrate=9600, timeout=0.5) data = ser.read(10) print(len(data))Assuming no data is sent to the port. | Raspberry Pi

Raspberry Pi - Serial UART Communication

What will be the output of this code snippet?

import serial
ser = serial.Serial('/dev/ttyS0', baudrate=9600, timeout=0.5)
data = ser.read(10)
print(len(data))

Assuming no data is sent to the port.

AError: timeout too short

B10

CNone

D0

Step-by-Step Solution

Solution:

Step 1: Understand ser.read with timeout and no data
ser.read(10) tries to read 10 bytes but waits only 0.5 seconds.
Step 2: Since no data arrives, read returns empty bytes
len(data) will be 0 because no bytes were received before timeout.
Final Answer:
0 -> Option D
Quick Check:
Read length with no data = 0 [OK]

Quick Trick: Read returns empty bytes if no data before timeout [OK]

Common Mistakes:

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What will be the output of this code snippet?