Documented ROM Subroutines
There are a few subroutines available for machine language programs in the Color BASIC ROM that are available for general purpose programming.
POLCAT, address : polls keyboard for a character
CHROUT, address : outputs a character to screen or device
CSRDON, address : starts cassette and prepares for reading
BLKIN, address : reads a block from cassette
BLKOUT, address : writes a block to cassette
JOYIN, address : reads joystick values
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