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IGCSE Computer Science 0478 — 3.1 Computer Architecture

Inside the CPU — registers, buses and the fetch-decode-execute cycle.

Modules (35)

1 Input, process, output and storage 2 Central processing unit (CPU) 3 Memory (RAM) 4 Microprocessor 5 Von Neumann architecture 6 Arithmetic logic unit (ALU) 7 Control unit (CU) 8 Registers 9 Program counter (PC) 10 Memory address register (MAR) 11 Memory data register (MDR) 12 Current instruction register (CIR) 13 Accumulator (ACC) 14 Buses 15 Address bus 16 Data bus 17 Control bus 18 The fetch-decode-execute cycle 19 Fetch: sending the address from the PC to the MAR 20 Fetch: reading the instruction from RAM into the MDR 21 Fetch: incrementing the PC and copying the instruction to the CIR 22 Decode stage 23 Execute stage 24 Tracing one instruction through the registers 25 CPU clock speed (GHz) 26 CPU cores 27 Cache memory 28 How cores, cache and clock affect CPU performance 29 Instruction set 30 Machine code 31 Embedded system 32 Devices that use embedded systems 33 General-purpose computer 34 Embedded systems compared with general-purpose computers 35 Writing exam answers about the CPU

Printables for this journey

Every module above has its own free printable worksheet with an answer key. These crosswords and word searches cover the same terms:

Years 5–6 Digital Systems Crossword: Inside digital systems (Modules 1–10) 10 clues · Digital system, Hardware, Software, Input, process, output and storage and more

Years 5–6 Digital Systems Word Search: Inside digital systems and Data and networks (Modules 1–20) 20 words to find · Digital system, Hardware, Software, Input, process, output and storage and more

Years 7–8 Digital Systems Crossword: Hardware for particular tasks (Modules 4–19) 10 clues · CPU clock speed (GHz), CPU cores, HDD vs SSD performance, Storage units: KB, MB, GB, TB and more

Years 7–8 Digital Systems Word Search: Hardware for particular tasks to Account security and cyber threats (Modules 4–74) 20 words to find · CPU clock speed (GHz), CPU cores, HDD vs SSD performance, Storage units: KB, MB, GB, TB and more

Crossword: 2.3 Encryption and 3.1 Computer Architecture (Modules 204–217) 10 clues · Private key, Encrypting with the recipient's public key, Decrypting with the private key, Sending a secure message with asymmetric encryption and more

Crossword: 3.1 Computer Architecture (Modules 218–227) 10 clues · Registers, Program counter (PC), Memory address register (MAR), Memory data register (MDR) and more

Crossword: 3.1 Computer Architecture (Modules 228–239) 10 clues · The fetch-decode-execute cycle, Fetch: sending the address from the PC to the MAR, Fetch: reading the instruction from RAM into the MDR, Fetch: incrementing the PC and copying the instruction to the CIR and more

Crossword: 3.1 Computer Architecture and 3.2 Input and Output Devices (Modules 240–251) 10 clues · Machine code, Embedded system, Devices that use embedded systems, General-purpose computer and more

Word Search: 2.2 Methods of Error Detection to 3.1 Computer Architecture (Modules 189–217) 20 words to find · Choosing an error detection method for a scenario, Interception of data on a network, Plaintext, Ciphertext and more

Word Search: 3.1 Computer Architecture (Modules 218–239) 21 words to find · Registers, Program counter (PC), Memory address register (MAR), Memory data register (MDR) and more

Word Search: 3.1 Computer Architecture and 3.2 Input and Output Devices (Modules 240–261) 22 words to find · Machine code, Embedded system, Devices that use embedded systems, General-purpose computer and more

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