---
title: "Bit rate, baud rate and character time at 9600"
subject: "Instrumentation II"
chapter: 3
key: "semester_5/instrumentation_ii:baud-time-engineer"
source: https://www.bctengineer.com/q/semester_5/instrumentation_ii/baud-time-engineer
site: BCT Engineering
---

# Bit rate, baud rate and character time at 9600

Instrumentation II · Chapter 3: Serial Interfacing With Microprocessor Based System

- Asked in: 2078 Kartik, 5 marks
- Video: [bit rate and baud rate in hindi | Niharika Panda](https://www.youtube.com/watch?v=11mtP153Xg8) — Education 4u - Hindi
- Answer checked by Claude Sonnet 5.5 on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_5/instrumentation_ii/baud-time-engineer
- Whole chapter: https://www.bctengineer.com/md/semester_5/instrumentation_ii/chapter-3

## Question

Define bit rate and baud rate. Determine a character transmission rate using asynchronous serial data transfer method at baud rate 9600. Suppose a character has 7 bits data, one bit start bit, two bits stop bit and none parity. Calculate the time required to send a word: Engineer.

## Short answer

Bit rate is bits per second, baud rate is signal changes per second; for binary signaling they are equal. A 7-data-bit, 1-start, 2-stop frame has 10 bits. At 9600 baud, character time = 10/9600 = 1.0417 ms, giving 960 characters/s. Sending the word 'Engineer' (8 characters) requires 8 × 1.0417 = 8.33 ms.

## Answer

#### Definitions
- **Bit rate:** number of bits transmitted per second (bps).
- **Baud rate:** number of signal changes (signalling elements or symbols) per second. For binary signalling, as in RS-232 where each element carries one bit, baud rate = bit rate. With multi-level coding, bit rate = baud rate x bits per symbol.

#### Character frame
1 start + 7 data + 0 parity + 2 stop = **10 bits per character**.

#### Calculation at 9600 baud (9600 bps)
```text
 Bit time        = 1 / 9600            = 0.10417 ms
 Character time  = 10 x 0.10417 ms     = 1.0417 ms
 Character rate  = 9600 / 10           = 960 characters/s
 "Engineer" has 8 characters
 Time            = 8 x 1.0417 ms       = 8.33 ms
```
**Answer: character transmission rate = 960 characters/s; time to send "Engineer" = 8.33 ms** (80 bits / 9600 bps).

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. When are bit rate and baud rate equal?
   A. With multi-level coding
   B. When each signal element carries one bit
   C. Never
   D. Always
   Answer: B. Bit rate = baud rate x bits per symbol, so for binary signalling they are equal. (Key point: Bit vs baud)

2. How many bits per character with 1 start, 7 data, no parity, 2 stop?
   A. 11
   B. 8
   C. 10
   D. 9
   Answer: C. 1+7+0+2 = 10 bits. (Key point: Frame size)

3. What is the character rate at 9600 baud?
   A. 9600
   B. 96
   C. 1200
   D. 960 characters/s
   Answer: D. 9600/10 = 960 characters per second. (Key point: Character rate)

4. Time to send Engineer (8 characters)?
   A. 10 ms
   B. 1.04 ms
   C. 0.83 ms
   D. 8.33 ms
   Answer: D. 80 bits / 9600 = 8.33 ms. (Key point: Total time)

## Related in Instrumentation II

- [Character transmission time at 1200 baud](https://www.bctengineer.com/question.md?key=semester_5%2Finstrumentation_ii%3Abaud-time-1200) — Instrumentation II, chapter 3, asked 2×
- [Asynchronous serial transfer of a character](https://www.bctengineer.com/question.md?key=semester_5%2Finstrumentation_ii%3Aasync-7bit-ascii-2stop) — Instrumentation II, chapter 3
- [RS-232C importance; time to transmit a string at 4800 baud](https://www.bctengineer.com/question.md?key=semester_5%2Finstrumentation_ii%3Ars232c-string-time-4800) — Instrumentation II, chapter 3
- [Error detection in serial data transmission](https://www.bctengineer.com/question.md?key=semester_5%2Finstrumentation_ii%3Aserial-error-detection) — Instrumentation II, chapter 3, asked 2×

## Related in other subjects

- [Synchronous vs asynchronous serial transmission](https://www.bctengineer.com/question.md?key=semester_4%2Fmicroprocessor%3Async-async-serial) — Microprocessor, chapter 4, asked 3×
- [Parity bits and 3-bit even parity generator](https://www.bctengineer.com/question.md?key=semester_3%2Fdigital_logic%3Aparity-even-generator-3bit) — Digital Logic, chapter 4, asked 2×
- [Parity bits and 3-bit odd parity generator](https://www.bctengineer.com/question.md?key=semester_3%2Fdigital_logic%3Aparity-odd-generator-3bit) — Digital Logic, chapter 4, asked 2×
- [8085 ALP: odd parity transfer with bit change](https://www.bctengineer.com/question.md?key=semester_4%2Fmicroprocessor%3Aalp-8085-odd-parity-transfer) — Microprocessor, chapter 2