Alignments, Adjustments
GB 49
CDR Mozart
8.
8.
Alignments, Adjustments
See instructions given by ComPair
9.
Circuit Description
Available circuit descriptions:
•
The basics of Compact Disc Recordable/Rewritable
–
4822 725 25242
•
3
rd
generation Compact Disc Recording
–
3104 125 40100
9.1
Mozart Main Board
The Mozart Main Board is a Processing board (PCB) that has
following functionality :
•
Control CDR device (FREYA / RACOON) (open/close/
play/record/search/skip/..)
•
Control CD device (3CDC or 3DTC) (Play/search/skip/..)
(Only open/close/rotate tray is done by display uP)
•
Digital audio processing (MP3 decoding, analog/digital
input stage, analog/digital output stage)
•
Display I
2
C interface
High level functionality is as follows:
The Mozart Main board (called Mozart) is controlled by the
display uP (user interface) by means of an I
2
C interface.
Mozart can control the CDR at high level. All servo issues are
integrated in the CDR module. High level commands are
transmitted to CDR for play, record, read TOC, search, skip
songs, etc...
Control of the CD module is similar except that during
initialization, Mozart has to set some servo settings of the CD
module.
Mozart controls the analog/digital back-end, performs analog
to digital and digital to analog conversion.
9.2
Play-Back
Mozart can play both plain digital audio and MP3 files. In
principle both systems operate in the same way.
Mozart sends play command to CDR/CD module. Both
modules have EBU output. Mozart routes these signals
internally to an EBU output and an IIS output.
The EBU output of Mozart is converted to 0.5Vpp. This 0.5V
signal is routed to an I/O interface.
The IIS signal is routed to a DAC (pos7311). This one
performs a digital to analog conversion and after filtering the
analog output is brought to an I/O interface.
9.3
Recording
Mozart can record from both analog and digital sources.
Digital input (EBU) is routed from I/O board to Mozart.
Record-able audio is sent to the CDR module by means of an
IIS interface.
External analog source recording goes trough a digital
potentiometer (pos 7402) to adjust level. Analog to digital
conversion is done by a ADC (pos 7312). IIS output of the
ADC is input for Mozart (pos 7000). This IIS signal is routed
internally to an IIS output (input for the CDR module).
Double-deck sets have the ability to do internal copies. The
CD plays back the original disc. The EBU output of the CD is
routed to the IIS input of the CDR module.
Discs with copy-protection can not be copied digitally. Analog
switch 7301 routes back the analog output to the analog
input.
9.4
Processor Environment
9.4.1
Mozart IC
Overview
The Mozart MCF5248 integrated microprocessor combines a
processor with the following modules.
•
Multiply-accumulate (MAC) unit
•
DRAM controller
•
DMA controller
•
Timers
•
Parallel and serial interfaces
•
System integration module (SIM)
•
USB slave interface
•
Multiport digital audio interface
The IC is designed for embedded control applications.
The integrated MAC module enhances the device's DSP
functionality through support of high-speed, complex,
arithmetic operations.
The digital audio functionality includes four serial audio
interfaces (Philips and SONY formats supported) and one
IEC958. Three serial audio receivers, and two serial audio
transmitters, each of are programmable to operate in a
variety of modes. The IEC958 input has four possible
external sources and selection of these sources is
programmable.
Included in the IC is an oscillator that allows either a 16.93
MHz or 33.86 MHz crystal as the primary clock input. From
this oscillator, a 16.93 MHz clock signal is derived to drive the
digital audio logic. This same clock is multiplied in an internal
PLL to generate the processor clock, bus clock and USB
slave clock. These clocks drive the processor, the bus and all
internal logic.
The USB slave interface allows interfacing with PC
applications.
Note: To ensure that the USB functions correctly, the
processor must run at 96MHz.
The MAC unit is optimised to provide good performance on
typical digital audio algorithms such as MP3 decoding and
sample rate conversion.
Multiport digital audio interfaces:
•
Digital audio interfaces
–
IEC958 input and output
–
Four serial Philips IIS/Sony EIAJ interfaces Two with
inputs and outputs, one with input only, one with
output only
•
CD text interface
–
Allows the interface of CD subcode
•
Crystal trim
–
XTRIM output locks the crystal to an incoming
IEC958 or serial audio signal
•
USB slave interface
•
DMA controller
•
Dual universal synchronous/asynchronous receiver/
transmitter (Dual UART or RS232)
•
I
2
C interface
–
Interchip bus interface for EEPROMs, LCD
controllers, A/D converters and keypads
–
Master and slave modes support multiple masters
•
System interface
–
Bus interface with chip selects and DRAMC support
for interface to 16-bit for DRAM, SRAM, ROM,
FLASH, and I/O devices
•
Clocking by Clock-multiplied PLL
