Assembly Tracing
Complete trace tables for assembly programs, line by line, as in 9618 Paper 1.
Number Systems
Understand binary, denary and hexadecimal side by side: change one and watch the other two follow, with the working.
Circuit Dash
Call the output of ever-bigger logic circuits before the clock runs out.
Run the CPU
Be the control unit: fetch, decode and execute real programs, fast.
Hexa-Tac
Shoot down falling invaders by typing their code in hex.
Pixel Painter
Compress an image with run-length encoding before time runs out.
Bits on the Wire
Send a message down the cable as bits: serial, parallel, skew and crosstalk.
Parity Check
Work out parity bits, and find and fix the flipped bit in a parity block.
Normal Form or Not?
Is a database in third normal form? Find what stops it and fix it, step by step.
Trace Tables
Trace real 9618 pseudocode and flowcharts, one variable at a time.
Schema Architect
Design linked tables with keys, then write the DDL yourself.
File Sizes
Work out how big text, images and sound files are, bit by bit.
SQL Challenges
Query a real database in SQL to answer questions about it, with every query checked and explained.
How a Web Page Loads
Follow one web page from the address bar to the screen: DNS lookup through the root, TLD and authoritative servers, the TCP handshake, TLS, HTTP and every file the HTML asks for, with a waterfall of the timings.
Packet Routing
Watch numbered packets cross a mesh of routers, each following its own routing table; break a link, congest one or fail a router and see the tables update, packets re-route and arrive out of order, and the message reassembled.
Device Dash
Devices fall towards three bins: sort each into input, output or storage before it lands, then pick the best device for a real job, from MICR for cheques to RFID for cattle ear tags.
Phish or Legit?
Emails, texts, calls and web pages fill your inbox: trust or report each before it overflows, then name the threat and the right defence.
Validation Station
Records stream towards the database: pick the validation check that catches each bad value, tell validation from verification, and sort test data into normal, abnormal and extreme.
Network Builder
Place routers, switches, wireless access points and modems, connect a LAN, a WLAN and a WAN, then send a message and watch each device forward it by MAC or IP address.
Who Gets In?
Layer passwords, biometrics, 2FA, a firewall, encryption, anti-malware and access rights, then send in nine attacks and see which defence stops each one, and what it costs.
Packet Journey
Follow a web request from DNS lookup to packets routed on their own and reassembled in order, then see how bandwidth, latency and packet loss change load time.
Vector or Bitmap?
Zoom in until the bitmap pixelates while the vector stays sharp, compare file sizes, edit layers and pixels, then choose the right format for 14 real jobs.
Edit Suite
Trim, split, fade and mix clips on a timeline without clipping, then see how sample rate, resolution, frame rate and lossy or lossless compression change the file size.
Control Loop
Run a greenhouse or central heating: sensors, ADC, microprocessor and actuators in a feedback loop, with its graph and flowchart.
Encryption Lab
Encrypt with Caesar or XOR, meet the key-sharing problem, then watch public keys, digital signatures and an HTTPS handshake step by step.
Flowchart Runner
Choose or build a flowchart and run it box by box with a live trace table, then predict outputs and fix faulty flowcharts.
Expert System Builder
Consult a plant doctor or car-fault expert system, watch backward and forward chaining fire its rules, then edit the rules yourself.
File Access Visualiser
Serial, sequential, indexed sequential and hashed files side by side: search, add and delete, count the accesses, then batch-update a master file.
Tamper-Proof Chain
Edit a block in a real SHA-256 blockchain and watch every later link break, then mine to fix it; weigh up the uses and limits of digital currencies.
IGCSE Pseudocode
Write Cambridge IGCSE pseudocode, checked strictly against the 0478 rules, then run it, step through it with a trace table, and have it marked on tests.
AS Pseudocode
Write 9618 pseudocode to Paper 2 specifications: functions, procedures, BYREF, strings, records, sorting, searching and text files, run, traced and marked on tests.
A Level Pseudocode
Write A Level 9618 pseudocode: recursion, binary search, insertion sort, stacks, queues and linked lists, classes and inheritance, and random files, all run and marked on tests.