jw002.asm

一款MP3 Player Firmware 的原代码,非常有参考价值

; Display board firmware, to allow the JW-002 display board to be
; used with the PJRC MP3 Player:   http://www.pjrc.com/tech/mp3/
; The JW-002 display board may be purchased from PJRC.COM, with
; this firmware installed and an adaptor board with 12 pushbuttons
; and two cables to allow it to connect directly to the PJRC MP3
; player circuit board's 4-pin connector.

; The JW-002 display board may also be purchased directly from
; Earth Computer Tech, at:  http://www.flat-panel.com/jw002.htm
; Earth will offer quantity discounts, so for applications other
; than use with the PJRC MP3 player, Earth may be a better choice
; for purchasing the display.  They provide the JW-002 without
; the extra parts needed for use with the PJRC MP3 player board.

; This JW-002 firmware source code has been placed in the public domain.
; This code is provided in the hope that it will be useful, but
; it is provided without any warranty; without even the implied
; warranty of merchantability or fitness for a particular purpose. 


;TODO: handle pushbutton "ghosts" (eg if you press #2, #3 and #4
;  at same time, #10 appears as a ghost).


	;configurable (but hard-coded) settings

	.equ    location, 0x0000	;stand-alone build
	;.equ    location, 0x8000	;to run under PAULMON2 (see below)

	;.equ	baud_const, 255		;57600 baud
	.equ	baud_const, 253		;19200 baud
	;.equ	baud_const, 250		;9600 baud


; ******************************************************************



	;internal memory allocation

	.equ	reg0, 0
	.equ	reg1, 1
	.equ	reg2, 2
	.equ	reg3, 3
	.equ	reg4, 4
	.equ	reg5, 5
	.equ	reg6, 6
	.equ	reg7, 7
	.equ	rx_buf_head, 0x08	;1 byte
	.equ	rx_buf_tail, 0x09	;1 byte
	.equ	tx_buf_head, 0x0A	;1 byte
	.equ	tx_buf_tail, 0x0B	;1 byte
	.equ	x_pos, 0x0C		;1 byte, current x char position
	.equ	y_pos, 0x0D		;1 byte, current y char position
	.equ	font, 0x0E		;1 byte, current font to use
	.equ	cmd_len, 0x0F		;1 byte, # of chars revc
	.equ	cmd_buf, 0x10		;16 byte command buffer
	.equ	hscroll_en, 0x20	;1 byte
	.equ	mode_bits, 0x21		;3 bytes
	.equ	vscroll_offset, 0x24	;1 byte, current y scroll offset
	.equ	pb_scan_state, 0x25	;1 byte
	.equ	char_buf, 0x26		;5 bytes, buffer of current char
	.equ	pb_state, 0x2b		;12 bytes, pushbutton state
	.equ	pb_config, 0x37		;12 bytes, config for each button
	.equ	pb_event_head, 0x43	;1 byte
	.equ	pb_event_tail, 0x44	;1 byte
	.equ	lcd_on_timer, 0x45	;1 byte
	.equ	redraw_addr, 0x46	;2 bytes


	.equ	hscroll_speed, 0x49	;1 byte
	.equ	hscroll_t0_count, 0x4a	;1 byte
	.equ	hscroll_fill_row, 0x4b  ;1 byte
	.equ	hscroll_font0, 0x4c	;1 byte
	.equ	hscroll_font1, 0x4d	;1 byte
	.equ	hscroll_font2, 0x4e	;1 byte
	.equ	hscroll_font3, 0x4f	;1 byte
	.equ	hscroll_font4, 0x50	;1 byte
	.equ	hscroll_font5, 0x51	;1 byte
	.equ	hscroll_font6, 0x52	;1 byte
	.equ	hscroll_font7, 0x53	;1 byte
	.equ	hscroll_end0, 0x54	;1 byte
	.equ	hscroll_end1, 0x55	;1 byte
	.equ	hscroll_end2, 0x56	;1 byte
	.equ	hscroll_end3, 0x57	;1 byte
	.equ	hscroll_end4, 0x58	;1 byte
	.equ	hscroll_end5, 0x59	;1 byte
	.equ	hscroll_end6, 0x5a	;1 byte
	.equ	hscroll_end7, 0x5b	;1 byte
	.equ	hscroll_pos0, 0x5c	;1 byte
	.equ	hscroll_pos1, 0x5d	;1 byte
	.equ	hscroll_pos2, 0x5e	;1 byte
	.equ	hscroll_pos3, 0x5f	;1 byte
	.equ	hscroll_pos4, 0x60	;1 byte
	.equ	hscroll_pos5, 0x61	;1 byte
	.equ	hscroll_pos6, 0x62	;1 byte
	.equ	hscroll_pos7, 0x63	;1 byte
	.equ	stack, 0x64		;28 byte stack

	;bit mapped memory allocation (4 bytes)
	;hscroll_en* must start at 0
	.equ	hscroll_en0, 0
	.equ	hscroll_en1, 1
	.equ	hscroll_en2, 2
	.equ	hscroll_en3, 3
	.equ	hscroll_en4, 4
	.equ	hscroll_en5, 5
	.equ	hscroll_en6, 6
	.equ	hscroll_en7, 7
	.equ	wrap_mode, 8
	.equ	vscroll_mode, 9
	.equ	ignore_input_mode, 10
	.equ	cin_serviced, 11
	.equ	tx_intr_expected, 12
	.equ	update_mode, 13
	.equ	hscroll_fill_en, 14
	.equ	hscroll_redraw, 15
	.equ	turn_lcd_on, 16

	;external data memory
	.equ	rx_buf_page, 0		;256 byte rx buffer, 0000 to 00FF
	.equ	tx_buf_page, 1		;256 byte tx buffer, 0100 to 01FF
	.equ	pb_strings_page, 2	;512 bytes, strings, 0200 to 03FF
	.equ    display_cache, 4        ;5 columns * 24 characters * 8 rows =
					;960 bytes, display cache 0400 to 07FF
					;redraw routine assumes 1k boundary alignment
	.equ	hscroll_buffer, 8	;8x256 byte bufferx for horizontal scrolling rows
	.equ	pb_events_page, 0x10	;256 byte event buffer, 0800 to 08FF
	.equ	fonts_start_page, 0x11	;28416 bytes for fonts, 1100 to 7FFF
					;this allows 22 fonts to be stored
	.equ	num_rom_fonts, 4	;4 fonts included in ROM


	;memory mapped interface to the LCD display controller chips
	.equ	left_cmd_wr, 0xFF00
	.equ	left_cmd_rd, 0xFF01
	.equ	left_data_wr, 0xFF02
	.equ	left_data_rd, 0xFF03
	.equ	right_cmd_wr, 0xFF04
	.equ	right_cmd_rd, 0xFF05
	.equ	right_data_wr, 0xFF06
	.equ	right_data_rd, 0xFF07

	;connections to the 8051 port pins
        .equ    pb_xmit_1, 0xB2         ;p3.2
        .equ    pb_xmit_2, 0xB3         ;p3.3
        .equ    pb_xmit_3, 0x97         ;p1.7
        .equ    pb_recv_1, 0x93         ;p1.3
        .equ    pb_recv_2, 0x92         ;p1.2
        .equ    pb_recv_3, 0x94         ;p1.4
        .equ    pb_recv_4, 0x90         ;p1.0
	.equ	led_pin, 0x91		;clear to turn on LED
	.equ	watchdog_pin, 0xB5	;toggle to clear watchdog timer
	.equ	bank_pin1, 0x95		;ROM memory bank selects
	.equ	bank_pin2, 0x96


;pushbutton config
;
; autorepeat delay: no autorepeat, 400 ms, 650 ms, 900 ms
; autorepeat speed: 3/sec, 5/sec, 8/sec, 12/sec
; xmit press event
; xmit depress event



;***********************************************************************
;**                                                                   **
;**                          Main Program                             **
;**                                                                   **
;***********************************************************************

	.org	location
	ljmp	begin

	.org	location+11
	ljmp	timer0_isr

	.org	location+35
	ljmp	uart_intr

.org    location+256
.db     0xA5,0xE5,0xE0,0xA5     ;signiture bytes
.db     35,255,0,0              ;id
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;user defined
.db     255,255,255,255         ;length and checksum (255=unused)
.db     "JW-002 LCD Firmware",0
.org    location+256+64         ;executable code begins here


; To allow for program development with PAULMON2, the JW-002 display
; board needs several modifications.
;
; 1: Program PAULMON2 (pm21_8.obj) into the flash chip.
;
; 2: Disable the watchdog timer: short C1.
;
; 3: Disconnect the flash chip's CE pin from ground and connect it to
;    A15.  The wide trace that runs under the upper left corner of the 
;    PLCC socket is ground and only connects to CE, so this is the
;    trace to cut.  A15 may be found on a via 0.25 inches away from
;    the corner of this trace near the PLCC socket.
;
; 4: Connect PSEN and RD to an AND gate.  The two unused NAND gates
;    in IC2 may be used, if the pins are lifted away from the board.
;
; 5: Disconnect IC7's CE (pin 22) and connect it to the AND gate output.
;
; With these changes, this code may be built at 8000 and downloaded to
; the board.  Memory from 0000 to 7FFF will be both code memory (the
; flash chip with PAULMON2) and data memory (32k SRAM, IC8), and the
; firmware will use the SRAM starting at 0000 for fonts.  The code
; allows 32 fonts, but care should be taken not to use more than the
; first 22 fonts, as the 23rd font will begin to overwrite the program
; at 8000.


begin:
	mov	sp, #stack
	mov	ie, #0
	mov	psw, #0
	lcall	retinow
	lcall	retinow
	setb	update_mode
	lcall	init_display

	lcall	move_cursor_home
	mov	font, #0
	mov	cmd_len, #0
	setb	wrap_mode
	setb	vscroll_mode
	clr	ignore_input_mode
	clr	hscroll_fill_en
	clr	hscroll_redraw
	mov	hscroll_fill_row, #0
	mov	hscroll_en, #0
	mov	hscroll_font0, #0
	mov	hscroll_font1, #0
	mov	hscroll_font2, #0
	mov	hscroll_font3, #0
	mov	hscroll_font4, #0
	mov	hscroll_font5, #0
	mov	hscroll_font6, #0
	mov	hscroll_font7, #0
	mov	hscroll_speed, #0x06
	mov	hscroll_pos0, #0
	mov	hscroll_pos1, #0
	mov	hscroll_pos2, #0
	mov	hscroll_pos3, #0
	mov	hscroll_pos4, #0
	mov	hscroll_pos5, #0
	mov	hscroll_pos6, #0
	mov	hscroll_pos7, #0
	mov	hscroll_end0, #0
	mov	hscroll_end1, #0
	mov	hscroll_end2, #0
	mov	hscroll_end3, #0
	mov	hscroll_end4, #0
	mov	hscroll_end5, #0
	mov	hscroll_end6, #0
	mov	hscroll_end7, #0
	mov	hscroll_t0_count, #0

	lcall	init_uart_intr
	lcall	timer0_setup

	lcall	copy_fonts_to_sram

	mov	a, #location >> 8
	jz	main_loop
	mov	dptr, #mesg_abort
	lcall	pstr


main_loop:
	jnb	turn_lcd_on, main_event
	lcall	display_on
main_event:
	lcall	get_event
	jz	main_cont
	lcall	print_event
main_cont:
	jb	hscroll_redraw, main_hscroll_redraw
	lcall	cin
	jnc	main_got_char
	sjmp	main_loop
	
main_got_char:
	;lcall	cout			;uncomment for echo of input characters
	mov	r2, a
main1:	mov	a, cmd_len		;check if continuing multi-byte cmd
	jz	main2
	;if cmd_len > 0, this byte is to be treated at part of
	;a multi-byte command, and not regular input
	mov	a, #cmd_buf
	add	a, cmd_len
	mov	r0, a
	mov	a, r2
	mov	@r0, a
	inc	cmd_len
	acall	exec_cmd
	ajmp	main_loop
main2:	mov	a, r2			;check for 0x5C command
	cjne	a, #0x5C, main3
	;the '\' character, 0x5C, begin a command
	mov	r0, #cmd_buf
	mov	a, r2
	mov	@r0, a
	mov	cmd_len, #1
	;all '\' commands are at least two characters, so don't call exec_cmd
	ajmp	main_loop
main3:	mov	a, r2			;check for control character
	add	a, #224
	jc	main4
	mov	r0, #cmd_buf
	mov	a, r2
	mov	@r0, a
	mov	cmd_len, #1
	acall	exec_cmd
	ajmp	main_loop
main4:	jb	ignore_input_mode, main_loop	;check ignore input mode
	mov	a, r2
	lcall	lookup_char
	lcall	cache_char
	ajmp	main_loop


main_hscroll_redraw:
	mov	dph, #(hscroll_buffer - 1)
main_hscroll_redraw_next_row:
	inc	dph
	mov	a, dph
	cjne	a, #(hscroll_buffer + 8), main_hscroll_redraw_start
main_hscroll_redraw_exit:
	clr	hscroll_redraw
	ajmp	main_loop
main_hscroll_redraw_start:
	anl	a, #00000111b
	acall	check_hscroll_en
	jnc	main_hscroll_redraw_next_row
	mov	a, #0			;save params
	mov	c, wrap_mode
	rrc	a	
	mov	c, vscroll_mode
	rrc	a
	orl	a, x_pos
	mov	r2, a
	mov	r4, y_pos
	mov	r3, font
	mov	x_pos, #0		;init params
	mov	a, dph			
	anl	a, #00000111b
	mov	y_pos, a
	add	a, #hscroll_pos0	;get first char location
	mov	r0, a
	mov	dpl, @r0
	clr	c
	subb	a, #(hscroll_pos0 - hscroll_font0)
	mov	r0, a
	mov	font, @r0		;get font for this line
	add	a, #(hscroll_end0 - hscroll_font0)
	mov	r0, a			;point to end
	clr	wrap_mode
	clr	vscroll_mode
	mov	r1, #0
main_hscroll_redraw_next:
	movx	a, @dptr
	mov	r5, dph
	mov	r6, dpl
	lcall	lookup_char
	lcall	cache_char_only
	mov	dph, r5
	mov	dpl, r6
	inc	dpl
	inc	r1
	cjne	r1, #24, main_hscroll_redraw_cont
	sjmp	main_hscroll_redraw_complete
main_hscroll_redraw_cont:
	mov	a, dpl			;check for buffer wrap
	clr	c
	subb	a, @r0
	jnz	main_hscroll_redraw_next
	mov	dpl, #0
	sjmp	main_hscroll_redraw_next
main_hscroll_redraw_complete:
	mov	a, dph
	anl	a, #00000111b
	mov	r7, a
	mov	r5, dph
	lcall	redraw_row
	mov	dph, r5
	mov	a, r2		;restore params
	anl	a, #00011111b
	mov	x_pos, a
	mov	y_pos, r4
	mov	font, r3
	mov	a, r2
	rlc	a
	mov	vscroll_mode, c
	rlc	a
	mov	wrap_mode, c
	mov	a, dph
	anl	a, #00000111b
	add	a, #hscroll_pos0
	mov	r1, a
	inc	@r1
	mov	a, @r1
	clr	c
	subb	a, @r0
	jnz	main_hscroll_redraw_cont1
	mov	@r1, #0
main_hscroll_redraw_cont1:
	ljmp	main_hscroll_redraw_next_row



; checks whether the row specified in a is enabled for horizontal
; scrolling - result in c

check_hscroll_en:
	push	acc
	clr	c
	jnz	check_hscroll_en1
	mov	c, hscroll_en0
	sjmp	check_hscroll_done
check_hscroll_en1:
	dec	a
	jnz	check_hscroll_en2
	mov	c, hscroll_en1
	sjmp	check_hscroll_done
check_hscroll_en2:
	dec	a
	jnz	check_hscroll_en3
	mov	c, hscroll_en2
	sjmp	check_hscroll_done
check_hscroll_en3:
	dec	a
	jnz	check_hscroll_en4
	mov	c, hscroll_en3
	sjmp	check_hscroll_done
check_hscroll_en4:
	dec	a
	jnz	check_hscroll_en5
	mov	c, hscroll_en4
	sjmp	check_hscroll_done
check_hscroll_en5:
	dec	a
	jnz	check_hscroll_en6
	mov	c, hscroll_en5
	sjmp	check_hscroll_done
check_hscroll_en6:
	dec	a
	jnz	check_hscroll_en7
	mov	c, hscroll_en6
	sjmp	check_hscroll_done
check_hscroll_en7:
	dec	a
	jnz	check_hscroll_done
	mov	c, hscroll_en7
check_hscroll_done:
	pop	acc
	ret

;***********************************************************************
;**                                                                   **
;**                     Handle Control Characters                     **
;**                                                                   **
;***********************************************************************



exec_cmd:

	mov	r0, #cmd_buf
	mov	a, @r0
	cjne	a, #0x5C, exec_ctrl
	ajmp	exec_5c_cmd

exec_ctrl:

	;ESC Sequence
escape:	cjne	a, #27, ctrl_char
	ajmp	exec_esc

ctrl_char:
	jnb	ignore_input_mode, ctrl_a
	mov	cmd_len, #0
	ret

	;CTRL-A: Cursor Home
ctrl_a: cjne	a, #1, ctrl_h
	lcall	display_on
	lcall	move_cursor_home
	mov	cmd_len, #0
	ret

	;CTRL-H: Backspace
ctrl_h:	cjne	a, #8, ctrl_i
	mov	a, #1
	lcall	move_cursor_left
	mov	cmd_len, #0
	ret

	;CTRL-I: Tab
ctrl_i:	cjne	a, #9, ctrl_j
	mov	a, x_pos
	anl	a, #00000011b
	cpl	a
	inc	a
	add	a, #4
	lcall	move_cursor_right
	mov	cmd_len, #0
	ret

	;CTRL-J: Line Feed
ctrl_j:	cjne	a, #10, ctrl_k
	mov	a, #1
	lcall	move_cursor_down
	mov	cmd_len, #0
	ret

	;CTRL-K: Up one line
ctrl_k: cjne	a, #11, ctrl_l
	mov	a, #1
	lcall	move_cursor_up
	mov	cmd_len, #0
	ret

	;CTRL-L: Form Feed (clear display)
ctrl_l:	cjne	a, #12, ctrl_m
	lcall	init_display
	lcall	move_cursor_home
	mov	cmd_len, #0
	ret

	;CTRL-M: Carriage Return
ctrl_m:	cjne	a, #13, ctrl_u
	lcall	cursor_to_start_of_line
	mov	cmd_len, #0
	ret

	;CTRL-U: Forward
ctrl_u:	cjne	a, #21, crtl_unknown
	mov	a, #1
	lcall	move_cursor_right
	mov	cmd_len, #0
	ret

crtl_unknown:
	;just ignore unknown control characters
	mov	cmd_len, #0
	ret



;***********************************************************************
;**                                                                   **
;**                       Handle Escape Sequences                     **
;**                                                                   **
;***********************************************************************


	;0x1B 0x5B 0x41, move up one line
	;0x1B 0x5B 0x42, move down one line
	;0x1B 0x5B 0x43, move right one line
	;0x1B 0x5B 0x44, move left one line
	;0x1B 0x5B 0x48, cursor home
	;0x1B 0x5B 0x30 0x3B 0x37 0x6B, begin inverse text
	;0x1B 0x5B 0x30 0x6B, begin normal text
	;0x1B 0x5B 0x32 0x4A, clear screen

exec_esc:
	mov	a, cmd_len
	add	a, #254
	jc	exec_esc_1
	ret				;if len < 2, wait for more

exec_esc_1:
	mov	a, cmd_len
	add	a, #240
	jnc	exec_esc_2		;check if len >= 16
	mov	cmd_len, #0		;if len > 16, ignore input
	ret

exec_esc_2:
	mov	r0, #cmd_buf+1
	mov	a, @r0
	cjne	a, #0x5B, exec_esc_esc
	ajmp	exec_esc_5B

exec_esc_esc:
	cjne	a, #0x1B, exec_esc_unknown
	mov	a, #location >> 8
	jnz	exec_esc_abort
	dec	cmd_len			;ignore the 2nd ESC
	ret
exec_esc_abort:
	ljmp	0			;return to PAULMON2 on two ESCs


exec_esc_unknown:
	;just ignore unknown escape sequences
	mov	cmd_len, #0
	ret

exec_esc_5B:
	;TODO: this parsing really ought to allow numeric and ';'
	;characters and conclude that we have a complete escape
	;sequence when we get a alpha character A-Z or a-z.
	mov	a, cmd_len
	add	a, #253
	jc	exec_esc_5B_2
	ret				;if len < 3, wait for more

exec_esc_5B_2:
	mov	r0, #cmd_buf+2
	mov	a, @r0

exec_esc_5B_41:
	cjne	a, #0x41, exec_esc_5B_42
	jb	ignore_input_mode, exec_esc_unknown
	mov	a, #1
	lcall	move_cursor_up
	mov	cmd_len, #0
	ret

exec_esc_5B_42:
	cjne	a, #0x42, exec_esc_5B_43
	jb	ignore_input_mode, exec_esc_unknown
	mov	a, #1
	lcall	move_cursor_down
	mov	cmd_len, #0
	ret

exec_esc_5B_43:
	cjne	a, #0x43, exec_esc_5B_44
	jb	ignore_input_mode, exec_esc_unknown
	mov	a, #1
	lcall	move_cursor_right
	mov	cmd_len, #0
	ret

exec_esc_5B_44:
	cjne	a, #0x44, exec_esc_5B_unknown
	jb	ignore_input_mode, exec_esc_unknown
	mov	a, #1
	lcall	move_cursor_left
	mov	cmd_len, #0
	ret

exec_esc_5B_unknown:
	;just ignore unknown escape sequences
	mov	cmd_len, #0
	ret





;***********************************************************************
;**                                                                   **
;**                   Handle Custom Display Commands                  **
;**                                                                   **
;***********************************************************************


exec_5c_cmd:
	mov	a, cmd_len
	add	a, #254
	jc	exec_5c_cmd_1
	ret				;if len < 2, wait for more

exec_5c_cmd_1:
	mov	a, cmd_len
	add	a, #240
	jnc	exec_5c_cmd_2		;check if len >= 16
	mov	cmd_len, #0		;if len > 16, ignore input
	ret


	;cmd 0x5C <0x20-0x3F>, display bytes 0 to 31
exec_5c_cmd_2:
	mov	r0, #cmd_buf+1
	mov	a, @r0