Nightshade: Routine at E32C

Used by the routine at NEW_GAME.

Called once a turn by the main loop, at the end of the turn (NEW_GAME). Half-rows $7F and $FE are read together, so bit 0 is SPACE or CAPS SHIFT and bits 1-4 are the other eight keys of the two rows; the pause needs bit 0 and none of the others, so no key that plays the game starts one. It waits for the key to be let go, then for a press and a release, and the game goes on.

Pentagram's pause (and Alien 8's) is the same test and the same waits, but beeps as it pauses and as it goes on, and turns interrupts on while it waits; Nightshade's is silent and leaves them off.

Used by the routine at NEW_GAME. Called once a turn by the main loop, at the end of the turn (NEW_GAME). Half-rows $7F and $FE are read together, so bit 0 is SPACE or CAPS SHIFT and bits 1-4 are the other eight keys of the two rows; the pause needs bit 0 and none of the others, so no key that plays the game starts one. It waits for the key to be let go, then for a press and a release, and the game goes on. Pentagram's pause (and Alien 8's) is the same test and the same waits, but beeps as it pauses and as it goes on, and turns interrupts on while it waits; Nightshade's is silent and leaves them off.
PAUSE	E32C	LD A,$7E	Not SPACE or CAPS SHIFT, or another key of those two rows with it: no pause
	E32E	CALL READ_KEYS
	E331	BIT 0,A
	E333	RET Z
	E334	AND $1E
	E336	RET NZ
PAUSE_0	E337	LD A,$7E	Wait for the key to be let go...
	E339	CALL READ_KEYS
	E33C	BIT 0,A
	E33E	JR NZ,PAUSE_0
PAUSE_1	E340	LD A,$7E	...pressed again...
	E342	CALL READ_KEYS
	E345	BIT 0,A
	E347	JR Z,PAUSE_1
PAUSE_2	E349	LD A,$7E	...and let go
	E34B	CALL READ_KEYS
	E34E	BIT 0,A
	E350	JR NZ,PAUSE_2
	E352	RET