collapseos/arch/z80/rc2014/blk/604

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: (key)
( inc then fetch )
[ ACIAR> LITN ] C@ 1+ [ ACIA_BUFSZ 1- LITN ] AND
( As long as R> == W>-1, it means that buffer is empty )
BEGIN DUP [ ACIAW> LITN ] C@ = NOT UNTIL
DUP [ ACIA( LITN ] @ + C@ ( ridx c )
SWAP [ ACIAR> LITN ] C! ( c )
;
: (emit)
( As long at CTL bit 1 is low, we are transmitting. wait )
BEGIN [ ACIA_CTL LITN ] PC@ 0x02 AND UNTIL
( The way is clear, go! )
[ ACIA_IO LITN ] PC!
;