MCA-122 Microprocessors Notes for GGSIPU MCA Semester 2 run to 69 pages across 4 units, from 8086 architecture and assembly programming to peripheral chips, the 80386 to P6 and ARM7 family, and the 8051 and AVR microcontrollers. They include 14 assembly programs and 72 practice questions, mapped to the syllabus for the batch admitted 2025-26 onwards.
Written by Prateek Talwar, Founder, Unnati Educations · Reviewed by Ritik Rawat, B.Tech, Senior Full Stack Developer · Checked against the GGSIPU MCA scheme and syllabus PDF (01 Aug 2025) · Updated 13 October 2026 · Editorial policy
Scheme: MCA (2 years), affiliated institutes, A.S. 2025-26 onwards | Applies to: batch admitted 2025-26 onwards | Verified against: Scheme of Examination and Detailed Syllabus for MCA (BoS 28 Jul 2025, AC Sub Committee 01 Aug 2025)
MCA-122 Microprocessors at a glance: GGSIPU MCA Sem 2 credits, units and exam pattern
| Code and title | MCA-122 Microprocessors |
|---|---|
| Course and semester | MCA (2 years), Semester 2 |
| Category and credits | Core Elective I; L 3, T/P 1, 4 credits |
| Marks | 100: 40 internal + 60 end-term; pass mark 40 out of 100 |
| End-term pattern | Q1 compulsory short-answer on the whole syllabus (12 marks), then one of two questions per unit, 12 marks each (12 + 48 = 60 marks) |
| Applies to | Batch admitted 2025-26 onwards |
| Units | 4, with 10 teaching hours each |
| Related lab | MCA-168 Lab based on Core Elective I (Microprocessors Lab); L 0, T/P 2, 1 credit |
MCA-122 is one of ten Core Elective I choices among the other GGSIPU MCA Semester 2 papers.
These MCA-122 Microprocessors IPU notes follow the four units in order, each ending with questions that match this pattern. The scheme says the programme is governed by GGSIPU Ordinance 11.
MCA-122 Microprocessors Notes unit-wise: 14 assembly programs and 72 practice questions across 4 units
The official PDF gives MCA-122 units no titles, so these are the notes' titles. Notes for every other MCA paper sit under GGSIPU MCA notes.
MCA-122 Unit 1: Introduction, 8086 Architecture and Assembly Language Programming
Unit 1 traces the 4004-to-Core timeline, then builds the 8086: BIU and EU, registers, flags, 20-bit addressing, instruction groups and directives.
Pages 3 to 21 (19 pages), 7 sections, 5 assembly programs, 10 short-answer and 8 long-answer practice questions.
Quick look: hand-encoding MOV BX, CX (from page 14)
- Opcode
100010, D = 0 (CX is source), W = 1: byte 1 = 89H. - MOD = 11, REG = 001 (CX), R/M = 011 (BX): byte 2 = CBH.
- Machine code:
89 CB.
MCA-122 Unit 2: Memory and I/O Interfacing and Programmable Peripheral Devices
Unit 2 is hardware design: odd and even banks, a worked EPROM plus SRAM decoder, DRAM refresh, RS-232, the 8251A, 8255A, 8254, 8257, 8259A and 8279, and seven-segment codes.
Pages 22 to 38 (17 pages), 11 sections, 3 programs, 10 short-answer and 8 long-answer practice questions.
Quick look: 1 kHz square wave from 8254 Counter 1 with a 2 MHz clock (from page 33)
MOV AL, 76H ; Counter 1, mode 3
OUT CWR, AL
MOV AL, 0D0H ; 2000 = 07D0H, low byte
OUT CNT1, AL
MOV AL, 07H ; high byte
OUT CNT1, ALN = 2 MHz ÷ 1 kHz = 2000.
MCA-122 Unit 3: Advanced Microprocessors: 80186 to Pentium, P6 and ARM
Unit 3 is comparison theory: the 8086-to-Pentium table, the 8087, the 80486 pipeline, Pentium U and V pipes with MMX, the P6 instruction pool and the ARM7 barrel shifter.
Pages 39 to 53 (15 pages), 7 sections, no programs, 4 block diagrams, 10 short-answer and 8 long-answer practice questions.
| Basis | RISC | CISC |
|---|---|---|
| Instruction length | Fixed, e.g. 32-bit | 1 to 15 bytes |
| Cycles per instruction | Mostly 1 | Many |
| Memory access | Only LOAD and STORE | Many instructions |
| Control unit | Hard-wired | Micro-programmed |
Quick look: RISC (ARM, AVR) versus CISC (x86) (from page 50)
- Basis
- Instruction length
- RISC
- Fixed, e.g. 32-bit
- CISC
- 1 to 15 bytes
- Basis
- Cycles per instruction
- RISC
- Mostly 1
- CISC
- Many
- Basis
- Memory access
- RISC
- Only LOAD and STORE
- CISC
- Many instructions
- Basis
- Control unit
- RISC
- Hard-wired
- CISC
- Micro-programmed
MCA-122 Unit 4: 8051 Microcontroller and AVR RISC Microcontroller Architecture
Unit 4 covers the 8051 (PSW, pins, timers, RAM map, SFRs, interrupts, 111 instructions) and the AVR (32-register file, X/Y/Z pointers, EEPROM, ports, USART baud formula).
Pages 54 to 69 (16 pages), 3 sections, 6 programs, 10 short-answer and 8 long-answer practice questions.
Quick look: 1 ms delay with 8051 Timer 0, mode 1, 12 MHz crystal (from page 61)
MOV TMOD, #01H ; Timer 0, mode 1
MOV TH0, #0FCH ; 65536 - 1000 = FC18H
MOV TL0, #18H
SETB TR0 ; start
WAIT: JNB TF0, WAIT ; overflow?
CLR TR01000 cycles × 1 µs = 1 ms.
MCA-122 exam corner: 40 short-answer and 32 long-answer practice questions by unit
| Unit | Short-answer | Long-answer | Programs |
|---|---|---|---|
| Unit 1 (p20 to p21) | 10 | 8 | 5 |
| Unit 2 (p37 to p38) | 10 | 8 | 3 |
| Unit 3 (p52 to p53) | 10 | 8 | 0 |
| Unit 4 (p68 to p69) | 10 | 8 | 6 |
MCA-122 practice questions and programs per unit
- Unit
- Unit 1 (p20 to p21)
- Short-answer
- 10
- Long-answer
- 8
- Programs
- 5
- Unit
- Unit 2 (p37 to p38)
- Short-answer
- 10
- Long-answer
- 8
- Programs
- 3
- Unit
- Unit 3 (p52 to p53)
- Short-answer
- 10
- Long-answer
- 8
- Programs
- 0
- Unit
- Unit 4 (p68 to p69)
- Short-answer
- 10
- Long-answer
- 8
- Programs
- 6
The MCA-122 notes list 40 short-answer and 32 long-answer practice questions across 4 units, plus 14 assembly programs.
- Unit 1: Find the physical address if CS = 3400H and IP = 1A20H. Pointer: 34000H + 1A20H = 35A20H.
- Unit 2: 8255 control word: Port A input, Ports B and C output, mode 0? Pointer: D7 = 1, D4 = 1, rest 0:
1001 0000= 90H. - Unit 3: What is register renaming in P6? Pointer: 40 physical registers remove false dependencies.
- Unit 4: List the 8051 interrupts with vector addresses. Pointer: INT0 0003H, T0 000BH, INT1 0013H, T1 001BH, serial 0023H.
More practice sits in the MCA-122 important questions.
80386 operating modes in advanced microprocessors: excerpt from page 42 of the MCA-122 notes
Excerpt from page 42
Introduction and features
The Intel 80386, launched in 1985, was the first 32-bit x86 processor. It added paging, the virtual 8086 mode and a full 32-bit register set, and every later IA-32 processor is built on it. It came in two versions: the 80386DX with a 32-bit data bus and 32-bit address bus, and the 80386SX with a 16-bit data bus and 24-bit address bus.
- 32-bit ALU, registers, data bus and address bus, giving 4 GB of physical memory.
- 64 TB (246 bytes) of virtual memory per task.
- An on-chip memory management unit that supports both segmentation and paging with 4 KB pages.
- Three operating modes: real, protected and virtual 8086.
- Four privilege levels (rings 0 to 3) and hardware task switching through the TSS.
- A six-stage pipeline with a 16-byte prefetch queue, clocked at 16 to 33 MHz, plus debug registers with hardware breakpoints, in a 132-pin PGA package.
Real mode
Real mode is the default after reset, and the 80386 behaves like a very fast 8086. Only 1 MB is addressable through A0 to A19, using segment × 16 + offset with 64 KB segments. There is no protection and no paging; the mode exists to start the system and switch it into protected mode.
Protected mode
Protected mode is entered by setting the PE bit (bit 0) of CR0. It opens the full 4 GB physical and 64 TB virtual space. Segment registers now hold selectors that index the descriptor tables (GDT, LDT, IDT); each 8-byte descriptor gives a 32-bit base address, a 20-bit limit and access rights. This mode brings memory protection, privilege levels, paging and multitasking.
Virtual 8086 mode
Virtual 8086 mode is a special form of protected mode in which 8086 real-mode programs run as tasks under a protected-mode operating system. It is switched on by the VM bit (bit 17) of EFLAGS. Each V86 task sees its own 1 MB space, and paging can place that space anywhere in physical memory, so several DOS programs can run side by side safely.
Selector format (16-bit)
Bits 15 to 3 hold the index, which picks one of 8192 descriptors. Bit 2 is TI (0 selects the GDT, 1 the LDT). Bits 1 and 0 hold the RPL, the requested privilege level.
Do the MCA-122 notes cover the full GGSIPU syllabus?
Yes. Every official MCA-122 topic in all four units has a section in the notes; the check found no gap.
| Official unit | Official topics | Where in the notes | Status |
|---|---|---|---|
| Unit I | Evolution; microcomputer systems; 8086 pins, architecture, addressing modes, instruction formats and set; assembler programming, directives | Sections 1 to 6, p4 to p20 | Covered |
| Unit II | SRAM, ROM, DRAM interfacing; decoding and timing; I/O mapping; handshaking; serial standards; 8251A, 8255A, 8253/8254, 8257, 8259, 8279; LED displays | Sections 1 to 10, p23 to p37 | Covered |
| Unit III | 80186 to Pentium and 8087; 80386, 80486, Pentium models; MMX; P6; ARM7 | Sections 1 to 6, p40 to p52 | Covered |
| Unit IV | 8051 architecture, signals, addressing, interrupts, instructions, applications; AVR family, register file, ALU, memory, EEPROM, ports, timers, UART, interrupts | Sections 1 and 2, p55 to p68 | Covered |
MCA-122 official units mapped to the notes
- Official unit
- Unit I
- Official topics
- Evolution; microcomputer systems; 8086 pins, architecture, addressing modes, instruction formats and set; assembler programming, directives
- Where in the notes
- Sections 1 to 6, p4 to p20
- Status
- Covered
- Official unit
- Unit II
- Official topics
- SRAM, ROM, DRAM interfacing; decoding and timing; I/O mapping; handshaking; serial standards; 8251A, 8255A, 8253/8254, 8257, 8259, 8279; LED displays
- Where in the notes
- Sections 1 to 10, p23 to p37
- Status
- Covered
- Official unit
- Unit III
- Official topics
- 80186 to Pentium and 8087; 80386, 80486, Pentium models; MMX; P6; ARM7
- Where in the notes
- Sections 1 to 6, p40 to p52
- Status
- Covered
- Official unit
- Unit IV
- Official topics
- 8051 architecture, signals, addressing, interrupts, instructions, applications; AVR family, register file, ALU, memory, EEPROM, ports, timers, UART, interrupts
- Where in the notes
- Sections 1 and 2, p55 to p68
- Status
- Covered
Source: GGSIPU MCA Scheme of Examination and Detailed Syllabus, A.S. 2025-26 onwards (MCA-122 on PDF pages 60 to 62).
Every course in GGSIPU notes is mapped to its official PDF the same way.
Who writes and checks the MCA-122 8086 and 8051 notes?
- Prateek Talwar, author: Founder, Unnati Educations; Associate Company Secretary (ACS), ICSI, membership no. 58704, since 15 May 2019; B.Com, University of Delhi (School of Open Learning), 2012. Author profile
- Ritik Rawat, subject reviewer: Senior Full Stack Developer, Unnati Educations; B.Tech.
The 2026-27 edition maps all four units to the MCA scheme approved on 28 July 2025 for the 2025-26 batch. Last updated 13 October 2026; see our editorial policy.
The same team prepares GGSIPU important questions for every course.
MCA-122 and the GGSIPU MCA Sem 2 papers it connects to
The GGSIPU MCA syllabus pairs this elective with MCA-168, Lab based on Core Elective I, run as the Microprocessors Lab. The official PDF prints no practical list. Theory to lab:
- Unit 1 programs (p19 to p20) → lab objective 1, 8086 assembly programming.
- 8255, 8254 and display pages (p30 to p37) → objective 2, I/O interfacing.
- 8251A pages (p28 to p29) → CO4, chip-level serial communication.
Compulsory: MCA-102 Data and File Structures, MCA-104 Object Oriented Software Engineering, MCA-106 Python Programming. Other Core Elective I options: MCA-108 Advanced Database Management Systems, MCA-110 Data Warehousing and Data Mining, MCA-112 Mobile Applications Design and Development, MCA-114 Full Stack Development, MCA-116 Web Technologies, MCA-118 Theory of Computations, MCA-120 Software Testing, MCA-124 Embedded System, MCA-126 Information Security.
Open Elective I: MCA-128 Digital Marketing, MCA-130 Management Information System, MCA-132 Management Principles and Organizational Behavior, MCA-134 Finance and Accounting. MCA-124 lists microprocessor concepts as a pre-requisite, so the GGSIPU MCA Sem 2 Microprocessors notes also preview it.
How to write MCA-122 answers: block-diagram, control-word and assembly-program answers
MCA-122 answers come in three shapes. A 12-mark unit question usually wants a labelled block diagram and a register or signal walk-through; a control-word question wants the bit layout, the bits set and the hex result; a program question wants a full, commented assembly listing. Q1 short answers want two or three exact lines, such as a formula plus its worked result.
- Block-diagram answers. The notes' exam tips say: for 8086 architecture, draw the BIU and EU diagram, then explain both units, the registers, flags, segmentation and pipelining. The same shape fits the six-unit 80386 model (p43), the three-engine P6 diagram with the instruction pool in the middle (p49) and the ARM7 block diagram (p52).
- Control-word answers. Write the bit layout, mark each field, then convert. The notes practise the 8255 (91H, 80H, BSR 0BH) and the 8251A mode word FEH. Two traps the notes clearly flag: in an 8086 system the 8255 sits on D0 to D7, so only even port addresses (80H, 82H, 84H, 86H) are used; and EPROM sits at the top of memory because the 8086 restarts at FFFF0H.
- Assembly-program answers. Use the Unit 1 skeleton:
DATA SEGMENT,ASSUME CS:CODE, DS:DATA, load DS through AX, end withMOV AH, 4CHandINT 21H. On the 8051 there is no plainSUB: clear carry withCLR C, then useSUBB.
Worked example: enable 8051 Timer 0 and external INT1 interrupts (page 60)
IE, bit 7 to bit 0, is EA, -, ET2, ES, ET1, EX1, ET0, EX0. Set EA (bit 7), EX1 (bit 2) and ET0 (bit 1): 1000 0110 = 86H, so the answer is MOV IE, #86H.
Practise this format on GGSIPU MCA important questions.
MCA-122 8086 and 8051 notes FAQs
How do I get the full MCA-122 notes?
Message us on WhatsApp at 9899436384 and mention MCA-122. The full notes come as a printed book only; they are not sold as a PDF. Delivery takes 5 to 7 days at most, and the exact time depends on your location. The book has all 69 pages, with 14 assembly programs and 72 practice questions.
Do the MCA-122 notes match the 2025-26 GGSIPU MCA syllabus?
Yes. The MCA-122 notes follow the scheme and syllabus for MCA at affiliated institutes, effective from the 2025-26 academic year. Each official topic in Units I to IV has a section in the notes, including the AVR, P6 and ARM7 parts. The syllabus map above gives the notes page range for each official unit and topic group.
What is the passing mark for MCA-122 Microprocessors?
MCA-122 is marked out of 100: 40 internal and 60 end-term, where the end-term paper is a 12-mark compulsory Q1 plus four 12-mark unit questions, one from each unit. The MCA scheme of examination states pass marks as 40%, which is 40 out of 100. For end-term minimums and re-appear rules, check GGSIPU Ordinance 11 on ipu.ac.in.
Which MCA-122 unit has the most assembly programs?
Unit 4 has the most, with 6: four 8051 programs (adding five bytes, toggling P1.0, a 1 ms Timer 0 delay, serial transmit at 9600 baud) and two AVR listings for port I/O and USART set-up. Unit 1 follows with 5 programs for the 8086, Unit 2 has 3 interfacing listings, and Unit 3 is theory only.
Is MCA-122 compulsory in GGSIPU MCA Semester 2?
No. MCA-122 is one of ten options under Core Elective I in Semester 2, carrying 4 credits (L 3, T/P 1). You study it only if you choose it. If fewer than 20 students choose an elective, the scheme says no classes are held and it is completed through a MOOC platform such as SWAYAM.
Do the MCA-122 notes include the MCA-168 Microprocessors Lab practicals?
No. These are MCA-122 theory notes. They still help with MCA-168, because the 8086 programs in Unit 1 and the 8255, 8254 and display listings in Unit 2 match the two lab objectives: 8086 assembly programming and interfacing I/O devices. Use them to learn the logic and the expected output, then write your lab record yourself.
Get the full MCA-122 Microprocessors Notes on WhatsApp
| Unit | Pages | Page range |
|---|---|---|
| Unit 1: 8086 and assembly language | 19 | 3 to 21 |
| Unit 2: Interfacing and peripheral chips | 17 | 22 to 38 |
| Unit 3: 80186 to P6 and ARM | 15 | 39 to 53 |
| Unit 4: 8051 and AVR | 16 | 54 to 69 |
Pages per unit in the full MCA-122 notes book
- Pages
- 19
- Page range
- 3 to 21
- Pages
- 17
- Page range
- 22 to 38
- Pages
- 15
- Page range
- 39 to 53
- Pages
- 16
- Page range
- 54 to 69
The book has 69 pages with 14 programs, 15 diagrams and 72 practice questions. These are Microprocessors notes in English, sold as a printed book, not a PDF. Delivery: within 5 to 7 days at most; the exact time may vary with your location.
Order the full MCA-122 Microprocessors Notes book on WhatsApp (4 units, 69 pages)
Unnati Educations is an independent education provider based in Vikaspuri, Delhi. We are not affiliated with, authorised by, or endorsed by Guru Gobind Singh Indraprastha University (GGSIPU). 'GGSIPU' and 'IPU' are used only to describe the syllabus our notes follow. For official information, visit ipu.ac.in.
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