;	CP/M for M100, T102, T200
;
;	CONIN	Console In for M100, T102  ver 3.0
;
;	By Philip Avery 3-May-09
;
;
;	This routine switches from OptROM to Main ROM, checks the keyboard buffer, if zero - it waits.
;	Returns with the character in reg A. Switches back to OptROM.
;
;	Keyboard buffer is filled by key scan during Interrupt 7.5 process.
;
;	Requires System RAM to be present (F5F4H-FFFH)
;
;	Must be located above System ROM, ie within RAM 8000H - F5F3H.
;	-------------------------------------------------------------

	
;	M100 System RAM
keyboard_buffer_count	.equ	0ffaah
keyboard_buffer		.equ	0ffabh


Conin	push	psw
	push	b
	push	d
	xra	a	; Turn Off Option ROM (lower 32k RAM), ie enable System ROM
	out	0e0H
	call	44afh	; Turn on cursor
Conin1	lda	keyboard_buffer_count
	ora	a
	jz	Conin1
	dcr	a	
	sta	keyboard_buffer_count
	call	44bah	; Turn off cursor
	mvi	a,1	; Turn On Option ROM (lower 32k RAM)
	out	0e0H
	pop	d
	pop	b
	pop	psw
	lda	keyboard_buffer	; Get char from start of keyboard buffer
	ret

	.END