Question

500 Bytes of data needs to be transmitted from a UART every 100 ms. What should be the minimum transmission baud rate of UART, assuming 1 start bit, 8 data bits, and 2 stop bits?

1. 50000
2. 55000
3. 40000
4. 45000

Answer 1

Correct Answer - Option 2 : 55000

Bit Rate:

Bit Rate is the number of Bits that are converged or processed per unit. It is denoted by R_b.

Baud Rate: It is defined as no. of signal or samples processed per unit time.

\(Bit\;Rate = \frac{{Baud\;Rate}}{{No.\;of\;bits}}\)

NOTE:

If there is M symbols/sample then no. of Bits (n) = log² M

Solution:

Since 500 Bits of data processed by UART in 100 ms. Then

\(Bit\;Rate\;\left( {{R_b}} \right) = \frac{{500}}{{100 \times {{10}^{ - 3}}}} = 5\;kbps\) ∵ 1000 Bit Bit = 1 KB

Start bit = 1     Stop bit = 2        Data bit = 8

Total no. of Bits = 8 + 2 + 1 = 11

Baud Rate = No. of bits × R_b = 11 × 5 = 55 KBPS = 55000 BPS