![]() Picture 1: Connection material |
![]() Picture 2: Contact switches with key caps |
Storage media | pros | cons |
Floppy disk | cheap, easy exchange, no noise when idle. | slow, big, small storage capacity |
2.5"-harddisk | Notebook-harddisks do not need a 12V-voltage (only 5V) and are designed to be switched off and on quite often. | Adaptor needed to connect the 2mm-pin rows to a standard IDE-cable. |
3.5"-harddisk | high storage capacity | high power consumption, 5V and 12V required. |
Solid-state-disc | no noise, very small | very expensive, low storage capacity |
CDROM | No additional boot device needed | A special bootable CD has to be inserted on power on and the BIOS must be able to boot from a CD. |
![]() Picture 3: LCM 2x16 characters (here: without backlight) |
The LCM has got a TTL-compatible 8 bit bus that can be directly connected to the PC parallel port. The module can display 2 lines of 16 characters built of a 5x8 pixel matrix. The character set of the LCD controller (Hitachi HD44780) consists of ASCII- and special characters, Japanese katakana and 8 user definable characters. |
![]() Picture 4: ribbon cable soldered to the LCM |
The 25-pin Sub-D-connector must be connected to the 14 pin connector of the module according to table 2 using the supplied ribbon cable. This will be easier if you remove the plastics from the connector first like shown in picture 4. Some of the 14 wires (2, 3, 5) in the ribbon cable could theoretically be left away, however I suggest to connect all 14 wires to the LCM. |
![]() Picture 5: Power contacts for the LED backlight |
The LED backlight needs about 4 V and 200 mA. It must not
be
directly connected to the voltage of 5V from the power supply. You need
to use the 4.7 Ohm resistor to use 5V as supply voltage (see picture 5).
The power supply for the LCD (not for the backlight) can be taken from pin 14 of the PC parallel port (will be set high by LCDECHO). If there is no backlight, you can come along without the external +5V voltage this way. However, the voltage supplied by the parallel port might be off the range of 4.75V...5.25V which is the specified supply voltage for the LCD. |
![]() Picture 6: LCM with cables |
The ribbon cable has been soldered to the back of the module in order to prevent difficulties when assembling the chassis. The three lose wires are for 5V, Gnd and -5V. |
![]() Picture 7: Gaining the contrast voltage |
The contrast level is determined by the voltage applied to pin 3 of
the LCM. The lower the voltage, the darker are the pixels on the display.
The optimum level can be best adjusted with the potentiometer connected
to -5V and +5V like shown in picture 7. For most LCMs, the optimum level
of the voltage at pin 3 is negative (around -1 V).
If a -5V voltage is not available -12V can be taken instead. In this case, take care when adjusting the potentiometer because the contrast voltage must not exceed -5V. The potentiometer resistance should be around 10 kOhm. |
pin |
pin |
meaning |
|
|
Gnd (0V). Pin 18 to pin 25 are normally interconnected. Pin 18 is easiest to solder at because it is located nearer to the other used pins. |
|
|
+5V supply voltage, can be taken from the parallel port (see text!) |
|
|
Contrast level. The included LCM needs a negative voltage between 0V (no characters visible or only weak) and -5V (all pixels black). This voltage can be generated out of -5V or -12V using the potentiometer. Note that there are also LCMs which need a positive contrast voltage. |
|
|
Register select |
|
|
Read/Write. Grounded because LCDECHO does only write to the LCD. |
|
|
Enable |
|
|
Data (8 bits parallel, Pin 7 = LSB) |
|
|
LED-backlight anode (+5V) |
|
|
LED-backlight cathode (0V) |
The LCM can be easily tested using the LCDECHO utility:
GETPORT is a suitable utility to perform a function check. It reads
the 5 status lines of the parallel port and displays the bit pattern (1=key
pressed) as a number between 0 and 31. The highest value (16) is assigned
to the menu key, the other 4 keys represent from left to right the values
8, 4, 2 and 1. This order can be reversed with the option /M to
gain compatibility with an old version of the scheme.
The first job of MCP after startup is to check if there is a CD present
in the drive and whether it is a CD-ROM or an ordinary Audio CD. Depending
on the result of this "Autodetect"-procedure the user will be opposed to
one of the following three situations:
Result of the Autodetect-procedure | MCP section to be executed |
no CD presentk | main menu |
Audio-CD present | Audio-CD-subprogram |
CD-ROM (data) present | Directory-browser |
Main menu: | The main menu appears after startup if
no CD is present or after pressing the "menu"-key.
OPEN: Ejects the CD-tray. The eject-key of the drive itself should not be used because this could in some situations cause the operation system to print an error message (Abort, Retry, Fail?) that you will not be able to reply to. DRIVE: see below OPT: see below CLOCK: Displays a digital clock with 7-segment-digits |
DRIVE
CLOCK
OPEN OPT _ |
|
CTTY CALM _ |
Pressing the menu-key again will branch to this
tool-menu.
CTTY: A DOS-shell can be run and controlled via a serial port using a terminal(-program). LINK: This item is intended to run a data transfer utility. By default, LapLink will be called (not included). CALM: Spins down (most) IDE-diskdrives. BOOT: Reboots the system. |
Drive selection (DRIVE): | |
CD HARD RAM
ROM DISK DRIVE |
In the DRIVE menu you can choose between CDROM and harddisk (or other drives). |
Optionsmenü (OPT): |
"Continous Play" will automatically start the next title (in the directory) after playback has finished. In "shuffle-play" mode a random decision is made again without repeats. |
OFF ON* Skip |
|
OFF* ON Skip |
If you like, the harddisk motor can be switched off after bootup. |
OFF ON* Skip |
If present, title and author in the MP3-tags can be displayed as a scrolled text. |
OFF* ON Skip |
If a video card (or only some video RAM) is installed and if the computer is fast enough, this option displays the running time when decoding MP3-files. |
OFF ON* Skip |
If the MP3-tag has not already been found, the long filename from CD-ROMs in ISO 9660-level 2 format (up to 32 characters, only capital letters, digits and underscore) will be scrolled over the LCD. |
|
The configuration will be saved to disk for the next session. As this is the only write action, the player can be switched off at any other time without any loss of data. |
Audio-Track 001
SHUF <- -> PLAY |
After an audio-CD has been sucessfully detected the desired track can be selected or the decision can be done randomly (SHUF). If the "left arrow"-key is pressed while track 1 was selected, the last track number appears. The "right arrow"-key gets you back to the first track (wrapping). |
PAUSE << >> STOP |
The current track time time will be displayed during playback (after PLAY or SHUF). The fast-forward and fast-reverse keys jump 15 seconds ahead or back. |
01 CAMBODIA 2941
SHUF <- -> PLAY |
The upper display line informs
about the file number in the currend directory, the filename
and the filelength in kilobyte. The directory can be browsed with
the "arrow"-keys. The last file will be followed by the first but when
pressing the "left arrow"-key at the first file, subdirectories will occur.
This is especially important for "..". Holding an arrow-key down for a
longer time will speed up browsing.
PLAY either starts playback of the selected file or changes into the displayed directory. SHUF starts playback of a randomly chosen file in the current directory including all subdirectories. |
PAUSE << >> STOP |
The resident program KEYTSR generates keyboard scancodes for fast forward and fast reverse during the decoding process. The decoder will terminate when the STOP-key is held down. |
Entwicklung und Vertrieb von Hard- und Software
Klaus Peichl
Dornbergstr. 10
91058 Erlangen-Tennenlohe
Telephone (0 91 31) 60 40 63.
E-Mail: pei@01019freenet.de
WWW: http://www.01019freenet.de/pei
The latest version of this text can be found in HTML-format in the directory
"DOC" on the supplied floppy disk.
Copying this manual - even partially - requires my permission.
The software (except of shareware and freeware of other authors) must not
be copied and distributed.
All trademarks used in this document are acknowledged as being owned
by their respective owners.
(C) 1999-11-14 by Klaus Peichl