Tab inserts a tab. Esc, then Tab, leaves the editor. Ctrl+Enter assembles. Suggestions appear as you type: Up and Down choose, Tab or Enter accepts, Esc closes, Ctrl+Space asks for them.
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Code
↑ ↓ PgUp PgDn move · Enter follows a jump · Alt+← back · B breakpoint · E edit bytes · N NOP · Ctrl+Z undo · G go to
Memory
Scroll through all 64 KB. Click a byte, or use the arrow keys and Enter, to change it.