SCNKEY

Scan the keyboard
Categories:
Function AddressDescription
SCNKEY FF9FScan the keyboard

This routine scans the Commodore 64 keyboard and checks for pressed keys. It is the same routine called by the interrupt handler. If a key is down, its ASCII value is placed in the keyboard queue. This routine is called only if the normal IRQ interrupt is bypassed.

Example:
getKeyJSRSCNKEYScan keyboard
JSRGETINGet character
CMP#0Have we got a character?
BEQgetKeyNo then loop back
JMPCHROUTPrint it to the screen
Last modified October 19, 2021: Remove weighting so left index is now alphabetical (cbe7734)