3.3 Checking hardware
You need a proper software to test MPX
TM
. Refer to section 5.
4 MPX
TM
Internal
4.1 Overview
MPX
TM
is a multi-media decoding hardware, which supports mp3 in major. Currently, a separate
audio CODEC and DAC are included and MSX controls or sends data via a dedicated serial
interface. All commands from MSX are converted to serial data and transferred to the audio
CODEC. Multi-media data are also transferred to the CODEC by the same method. Such a parallel
to serial conversion is handled by a EPLD. Moreover, MPX
TM
R2 has a special FIFO memory to
reduce processing time of MSX. Multi-media data can be transferred through the FIFO memory
without checking whether data buffer is ready or not on every byte write.
MPX
TM
also has a flash memory for internal usage and user program interface. The flash memory is
divided into two areas called bank and physical 16KB memory segments can be mapped to any
bank dynamically.
Analog audio signals can be routed to DAC and you can mix mp3 musics from MPX
TM
with
external sound from DalSoRi OPL4 cartridge, for example. Each output and input levels can be
controllable. Mix all sounds from MSX together and enjoy it!
4.2 Board layout
Figure 2 shows the board layout of MPX
TM
. There are one LED and four connectors. The left two
connectors are used for audio input and the right two connectors are for audio output. You can
connect another audio equipments supporting line level inputs or outputs through those connectors.
Note that each audio level is controlled by software.
The LED indicates MPX
TM
is ready for receiving data from MSX. If it becomes darker when
playing musics, it means MPX
TM
is busy to decode multi-media data.
One slide switch is populated in MPX
TM
. If wrong software is installed into the flash memory and
thus MSX does not work correctly, you can disable the internal flash memory of MPX
TM
and save
your MSX from the malfunction. Also it’s safe that you disable the flash memory before MSX
boots, if you want to update software.
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2017 © Jun Soft
