readme.txt

DIY自己的MP3的参考价值极高的代码。含有详细的解释

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v2.12 - 2002-10-29
+eeprom is written only before power-off or USB connect, for extend eeprom life.
+added suport for card-specific graphical logo.
*bugfix in battery charge indication during stop.
*bugfix in artist name displaying if name is short.
*bugfix in fast forward volume decrease.
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v2.11 - 2002-10-23
*some small bugfixes in displaying function
*bugfix in next playlist change. Stack overflow generate this problem.
+little change in keylock icons
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v2.10 - 2002-10-21
+added total song time displaying.
*minior bugfix.
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v2.00 - 2002-10-20
+Big revolutions !!! Added support for graphisc LCD displays from 
 Nokia 3310,5110,5150,6110 or similar GSM phones.
 This firmware is BETA test version, and may have some bugs.

Modifications for LCD use (only boards older than Rev.C !):
1. Cut track from pin 1 of VS1001 to pin 5 of ATmega (DREQ sygnal).
2. Add in series (on cutting place) 10k (or 4k7) resistor.
3. Add 100nF capacitor from pin 4 of ATmega (RESET signal) to ground.
4. Add a 1uF or 2.2uF thantalum capacitor, - to GND, and + to pin 7 of LCD MODULE.
5. Connect the display with following scheme:

 LCD module  <-> yampp7
(pin 1) VDD   -  VCC*
(pin 2) SCLK  -  SCK  (pin 3 of ATmega)
(pin 3) SDIN  -  MOSI (pin 1 of ATmega)
(pin 4) D/C   -  DREQ (direct to pin 5 of ATmega)
(pin 5) SCE   -  SS   (pin 44 of ATmega)
(pin 6) GND   -  GND
(pin 7) VOUT  -  1 or 2.2uF capacitor to GND
(pin 8) RES   -  RESET (pin 4 of ATmega)

Looking at the Nokia 3310 display back side, connector up, counting from left
to right - the pins is numbered from 1 to 8. 
Check images on http://www.republika.pl/romek_by/y7photo.html for mounting example.
If you need any backlight for LCD, you may use pin 40 of ATmega instead of LED
output, and change "#define BACKLIGHT_TIME" in Constants.h file to non-zero value
On this case you have additional position in menu: Backlight Mode. Three modes
possible: Permanent OFF, Permanent ON, Auto mode.

+Keyboard layout is changed. Now is:

1. While playing song
                BUTTON_1        BUTTON_2        BUTTON_3        BUTTON_4        
ShortPress:     PLAY/PAUSE      STOP            NEXT            PREV
LongPress:      F.FWD           MENU            VOL UP          VOL DOWN

2. On Stop
                BUTTON_1        BUTTON_2        BUTTON_3        BUTTON_4        
ShortPress:     PLAY            STOP(NONE)      MBASS           RANDOM
LongPress:      PWR.OFF         MENU            Autolock ON/OFF LCD Contrast

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v1.13 - 2002-10-09
some falstarts in version 1.12 :(((
*fixed accidentally bootloader entering during keyboard lock/unlock
*fixed accidentally song change after keyboard unlocking
+added beeps for manual lock/unlock confirmation - high beep = ON, low = OFF.
 Beeps may be turn off by commenting LOCK_BEEP definition in "Constants.h" file.
+added option for autolock ON/OFF during normal operation. If you enable autolock
 function in "Constants.h", you may turn ON or OFF autolock functionality by 
 pressing VOL_UP key for long time during STOP condition. Status is confirmed 
 by beep - like MegaBass or Random status change. See updated keys layout.
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v1.12 - 2002-10-07
+added keyboard locking functions with autolock. For keyboard lock/unlock press
 and hold two top buttons (BUTTON 3 and BUTTON 4) for 1 second during play state.
 Lock and unlock be confirmed by led flashing until you release these keys.
 If you enable automatic lock function by setting AUTOLOCK_TIME to non-zero
 value (in Constants.h file), your keyboard be automatically locked after 
 defined time of playing, counted from last key touch. Autolock moment is
 confirmed too by LED flashing. Default is enabled after one minute.
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v1.11 - 2002-10-04
+added card removing checking during pause and stop mode
+code speed-up and cleaning
+added configurable CF standby time (in Constants.h file)

TIP:
If player cant startup after card changing (genetates series of beeps and
automatic power-off) - remove card, startup yampp, and insert card back during
the beep series.
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v1.10 - 2002-09-27
+ added true random function (max 1024 songs in playlist)
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v1.00 - 2002-09-23

First public release.

Features :
- Card present checking, if no card present or card removed - yampp go to sleep
  mode
- Automatic card formatting if card don't have YADL format. Insert new card and 
  power up yampp for card format.
- Additionally LED output on PB0 (need* mount LED and 2.2K resistor in series, 
  from pin 40 of ATmega103 to ground)
- Wakeup from sleep need press and hold "Play" key for two seconds
- Beep during playlist change, playlist <TOTAL> have different tone from other.
- Delay in keypress checking for avoid accidental key pressing.
- FastForward, Random, Loudness and Repeat functions.
- All functions is handled by 4 keys, layout is depending on playing state.
- Trap for vs1001 lockup if MP3 has garbage
- Manual power off -> longpress STOP key in Stop mode.
- Auto power of from pause state after 30 minutes
- Battery level monitoring (default disabled). This function need* small yampp 
  board modification by adding two resistors. One 33k from PB3 
  (pin 43 of ATmega) to ground, and second 51k from the same PB3 to VCC. 
  After this change you may enable "#define BATTERY_TEST" definition in 
  Constants.h file. Battery low level is signalised by LED blink during playing, 
  and short beep in 2 minute interval.
  After 15 minutes of playing with low battery level, yampp automatically go to
  sleep mode.
- Battery charging indicator (only LI-ION cells). This function need* one more 
  small board modification. You may connect pin 8 of MAX1811 (CHG output) to 
  pin 26 of ATmega (OC1B line). If you do this, and connect USB cable in STOP 
  condition, the LED switch blink parameters to long on / short off until battery
  is near end of charge. NOTE: At this point battery is charged about 80% of full
  capacity. To full charge you need about 15 minutes additional charging time.
  Automatic power off be disabled too, for avoid shutdown FTDI chip and 
  disconect power from some models of USB hubs.

(*) "C" revision of yampp-7 board (future) not need these modifications.
If you have "B" version of yampp-7 board you may find some modifications details
pictures in "yampp7_modif.zip" file(battery charge indication connection is not shown).

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Keyboard Layout:

1. While playing song
                BUTTON_1        BUTTON_2        BUTTON_3        BUTTON_4        
ShortPress:     PLAY/PAUSE      STOP            NEXT            PREV
LongPress:      F.FWD           NEXT_PL         VOL UP          VOL DOWN


2. On Stop
                BUTTON_1        BUTTON_2        BUTTON_3        BUTTON_4        
ShortPress:     PLAY            STOP(NONE)      MBASS           RANDOM
LongPress:      REPEAT          PWR.OFF         Autolock ON/OFF No function

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MegaBass, Loudness and Autolock functions ON/OFF is confirmed by beeps:
Low beep = OFF, High Beep = ON

Random mode is confirmed by count of beeps (from 1 to 4).
1 beep  - Play single playlist and stop at end,
2 beeps - Play all playlists,
3 beeps - Repeat playlist,
4 beeps - Repeat one song.