The Multimedia PC (MPC) was a recommended configuration for a personal
computer (PC) with a CD-ROM drive. The standard was set and named by the
"Multimedia PC Marketing Council", which was a working group of the
Software Publishers Association (SPA, now the Software and Information
Industry Association).
Specification of MPC-1:
CPU
Minimum requirement: 386SX (or compatible) microprocessor
RAM
Minimum requirement: 2 megabytes of RAM
Magnetic Storage
Requirement:
3.5-inch, high density (1.44-MB) floppy disk drive.
Minimum requirement: 30-MB hard disk drive.
Optical Storage
Requirement:
CD-ROM drive with sustained 150kB/second
transfer rate; average seek time of 1 second or less; 10,000 hours MTBF;
mode 1 capability (mode 2 and form 1 &
2 optional
); MSCDEX 2.2 driver that implements the extended audio APIs; subchannel Q
The drive must be capable of maintaining a sustained transfer rate of
150kB/sec. without consuming more than 40 percent of the CPU bandwidth
in the process. It is recommended that this capability be achieved for
read block sizes no less than 16K and lead time of no more than is
required to load the CD-ROM buffer with 1 read block of data.
It is recommended that the drive have on-board buffers of 64K and implement read-ahead buffering.
Audio
Requirement:
CD-ROM drive with CD-DA (Red
Book) outputs and a front panel volume control.
Requirement: 8-bit (16-bit recommended) digital-to-analog
converter (DAC) with linear PCM sampling; DMA or FIFO buffered transfer
capability with interrupt on buffer empty; 22.05 and 11.025 kHz sample
rate mandatory.
44.1 kHz sampling rate desirable; optional stereo channels; no more than
10 percent of the CPU bandwidth required to output 11.025 or 22.05 kHz;
no more than 15 percent for 44.1 kHz.
Requirement: 8-bit (16-bit recommended) analog-to-digital
converter (ADC) with linear PCM sampling, 11.025 kHz mandatory, (22.01
kHz, or 44.1 kHz sampling rate optional); DMA or FIFO buffered transfer
capability with interrupt on buffer full; microphone input.
Requirement: Internal synthesizer hardware with
multi-voice, multi-timbral capabilities, six simultaneous melody notes
plus two simultaneous percussive notes.
Requirement: Internal mixing capabilities to combine input
from three (recommended four) sources and present the output as a
stereo, line-level audio signal at the back panel. The four sources are:
CD Red
Book,
synthesizer, DAC (waveform), and (recommended but not required) an
auxiliary input source. Each input must have at least a 3-bit volume
control (eight steps) with a logarithmic taper.
A 4-bit or greater volume control is strongly recommended. If all
sources are sourced with -10dB (consumer line level: 1 milliwatt into
700 ohms=0dB) without attenuation, the mixer will not clip and will
output between 0 dB and +3 dB. Individual audio source and master
digital volume control registers and extra line-level audio sources are
highly recommended.
Video
Requirement:
VGA-compatible display adapter, and a color VGA- compatible monitor. A basic Multimedia PC uses mode 12h (640 x 480, 16 colors)
.
An enhanced configuration referred to as VGA+ is recommended with 640 x 480, 256 colors.
The recommended performance goal for VGA+ adapters is to be able to blit
1, 4, and 8 bit-per-pixel DIBs (device independent bitmaps) at 350K
pixels/second given 100 percent of the CPU, and at 140K pixels/second
given 40 percent of the CPU. This recommendation applies to run-length
encoded images and non-encoded images. The recommended performance is
needed to fully support high-performance applications, such as
synchronized audio-visual presentations.
User Input.
Requirement:
Standard 101-key IBM-style keyboard with
standard DIN connector, or keyboard that delivers identical
functionality utilizing key-combinations.
Requirement: Two-button mouse with bus or serial connector, with at least one additional communication port remaining free.
I/O
Requirement:
Standard 9-pin or 25-pin asynchronous serial port, programmable up to 9600 bits per second (BPS), switchable interrupt channel.
Requirement: Standard 25-pin bidirectional parallel port with interrupt capability.
Requirement: 1 MIDI port with In, Out, and Thru must have interrupt support for input and FIFO transfer.
Requirement: IBM-style analog or digital joystick port.
System Software
Multimedia PC system software must offer binary compatibility with
Microsoft Windows 3.0 with Multimedia Extensions or Windows 3.1.
Specification of MPC-2:
CPU
Minimum requirement: 25 MHz 486SX (or compatible) microprocessor.
RAM
Minimum requirement:
4 megabytes of RAM (8 megabytes recommended).
Magnetic Storage
Requirement: 160-MB or larger hard disk drive.
Optical Storage
Requirements:
CD-ROM drive capable of sustained 300 KB/sec.
transfer rate, average seek time of 400 milliseconds or less, CD-ROM XA
ready (mode 1 capable, mode 2 form 1 capable, mode 2 form 2 capable),
multisession capable.
At 300 KB/sec. sustained transfer rate it is recommended that no more
than 60 percent of the CPU bandwidth be consumed. It is recommended that
the CPU utilization recommendation be achieved for read block sizes no
less than 16K and lead time of no more than is required to load the
CD-ROM buffer with 1 read block of data.
Audio
Requirement:
16-bit digital-to-analog converter (DAC), 44.1
kHz sample rate mandatory, stereo channels; no more than 15 percent of
the CPU bandwidth be required to output 44.1 kHz.
Requirement: 16-bit analog-to-digital converter (ADC) with Linear PCM sampling; 44.1 kHz sample rate mandatory.
CD-ROM XA audio capability is recommended.
Support for the IMA adopted ADPCM software algorithm is recommended.
