Volex TTX2000 S Issue 1.2: Routine at 0AFA

0AFA: wait_and_decode_page: Wait for page_ready_flag, and check for key presses.

Used by the routines at init_variables, hold_page and warm_start_routine.
wait_and_decode_page	0AFA	CALL data_to_header_row
	0AFD	CALL display_header_row
	0B00	CALL detect_any_key	Call detect_any_key to detect if any key is pressed.
	0B03	AND A	If a key is pressed, call handle_keypress.
	0B04	JR Z,wait_and_decode_page_0
	0B06	CALL handle_keypress
wait_and_decode_page_0	0B09	LD A,(page_ready_flag)	Loop until page_ready_flag is set.
	0B0C	AND A
	0B0D	JR NZ,wait_and_decode_page_1
	0B0F	JR wait_and_decode_page
wait_and_decode_page_1	0B11	LD A,(inhibit_display)	If inhibit_display is not equal to zero jump back to wait_and_decode_page.
	0B14	AND A
	0B15	JR NZ,wait_and_decode_page
	0B17	CALL copy_page_data	Copy page data into display buffer.
	0B1A	LD A,(bright_attr)	Add 7 (white ink) to value in bright_attr and store the result in colour_attr.
	0B1D	ADD A,$07
	0B1F	LD (colour_attr),A
	0B22	XOR A	Clear skip_next_row_flag.
	0B23	LD (skip_next_row_flag),A	Clear skip_next_row_flag.
	0B26	LD (page_ready_flag),A	Clear page_ready_flag.
wait_and_decode_page_2	0B29	PUSH AF	Save A on stack as loop counter.
	0B2A	LD (row_number),A	Store count in row_number.
	0B2D	CALL decode_row	Call decode_row.
	0B30	CALL detect_any_key	Call detect_any_key to detect if any key is pressed.
	0B33	AND A	If any key pressed, call handle_keypress, balance stack, and jump back to wait_and_decode_page.
	0B34	JR Z,wait_and_decode_page_3
	0B36	CALL handle_keypress
	0B39	POP AF
	0B3A	JP wait_and_decode_page
wait_and_decode_page_3	0B3D	POP AF	Else pop loop counter off stack and increment it.
	0B3E	INC A	Else pop loop counter off stack and increment it.
	0B3F	CP $18	Execute loop 24 times then jump back to wait_and_decode_page.
	0B41	JR NZ,wait_and_decode_page_2
	0B43	JP wait_and_decode_page