Edexcel 1CP2 2.2.1: Characters: 7-bit ASCII
The free BugBot lesson that teach this point, a robot to try it on, and the past-paper questions that test it.
What it covers
In lesson F3.2 you met character codes: A is 65. This lesson is about where those numbers come from. A character set is an agreed list of characters and the number for each, so that a message written on one computer reads the same on another. The two that matter are ASCII and Unicode.
- ASCII
- The trouble with ASCII
- Unicode
- Storage: more characters cost more bits
- Working out text size
Or do it in the simulator, with tasks that mark themselves
Lessons that teach it
- F8.6 Characters: ASCII and Unicode Data representation
Character sets, bits per character, and why Unicode was needed.
Try it on a robot
The task from F8.6 Characters: ASCII and Unicode, running here. Change the program and press Run.
The specification is Edexcel's own document; this page says which of our lessons teach point 2.2.1 and is not endorsed by the board.