|Year of unit||1999|
|Year of introduction||1999|
|Today we listen to MP3s using
portable players or smartphones. In 1999 Taiwanese company
Macpower Peripherals shown a stand-alone MP3 player with CD
drive - the most popular medium for large data in late 1990s.
Macpower Peripherals wa sa company who made server racks and server-grade computers, so their first MP-ROM player was installed in a full-height SCSI external enclosure. You can see it in product announcement from Polish Enter magazine August 1999.
|Because server-like enclosure was just not
appropriate for high-end audio set or even an average radio
equipment in typical living room, European importers wanted
another, more user-friendly casing. It was quickly re-designed
to be more compact and use external power supply unit. One of
importers was German Conrad electronics who still offer
manual to download.
To listen to music, headphones (using front-panel connector) or amplifier (using cinch connectors on the rear) may be used.
It is important to supply proper voltage (12V) with positive tip plug. if not, internal fuse may blow.
1 - GND
2 - +12V DC 1-1.5A
Using external 12V (1-1,5A) power supply unit forced whole electronics to be re-designed adding 5V converter on-board. This is known as Model 0005. My unit is quite early, it has drive from 1998.
During playback, only ambiguous track number is displayed,
so having a CD full of MP3s in fancy directory tree gives chaos. I
suspect the player orders files not by tag, but by their position in
table of contents in CD's ISO filesystem.
The software in microcontroller driving display and track selection also doesn't look good. Some routines look like have been written together for debugging and not separated in release version... or maybe my MP-ROM player is just very early.
Example: When CD is inserted player looks in CD's table of contents for MP3s, their count is displayed on 7-segment display to indicate progress. Unfortunately modifying microprocessor's internal table of tracks is permanently connected with displaying them and display refresh, so after removing CDs clearing this table results in few seconds of mess in display.
I think instead of linking another gallery I'll describe here what is inside the player.
Here is the CPU, a W78E52 microcontroller with two Atmel PLDs as glue logic and 32kBytes of memory in IS62C256 chip. Rest of chips are glue logic. In distance there's Micronas MAS3507D chip which is the main MP3 decoder.
Display/User interface part. Many things are implemented using TTL 74xx chips, maybe because of poor microcontroller program. Here you can also see Jacs IRDC360 IR remote control chip. Its parameters are not present on manufacturer's site, but IRDC36x were NEC 6121-standard decoders. The closest thing is IRDC362 datasheet.
Here is analog part, from left: PT2255A volume controller, unidentified chip and PT2308 headphone amplifier. The connector comes from CD drive and is used to play Audio CDs using drive's own routines.