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1.7 Digital Signal Processor
1.7.1 Architecture
The DSP is an Analog Devices ADSP21065L processor. It boots from an EEPROM
SST20LE020, U462 [DSP PCB sheet 3, C7]. U462 accessed through boot memory space and
through external memory space 3. Either BMS or MS3 on the DSP will chip enable U462 and
then a standard write/read enable interface is used to address U462. The DSP is reset by the
microcontroller through RESET. Chip clock is locally provided through XTAL461 [A2] at 30 MHz
resulting in a 60 MHz internal clock speed.
1.7.2 Interface to Microcontroller
Besides the audio peripherals described in the previous section, the DSP only interface to the
microcontroller. The DSP receives data on FLAG4 (P10 on the micro), transmits data on FLAG5
(P11 on the micro) and FLAG11/P12 provide clocking. RESET/P13 provides the reset for the
DSP and the watchdog functionality. The interface signals are routed through CN341 [micropro-
cessor PCB sheet 2, C8] between DSP and microcontroller board.
1.7.3 Internal LED
The DSP displays a “heartbeat” signal to an internal LED on the DSP board though FLAG10.
1.8 Microcontroller
1.8.1 Overview
The microcontroller is clocked by X341 [D3] (12 MHz) and provides interfaces between nearly all
peripherals.
Table 6. Peripheral pins on the microcontroller
1.8.2 Interface to Remote
Relay of DSP information to the Remote. The DSP in the power stand needs to transfer the clip
state, channel volume data (cause the table for channel volume in the DSP), system working
status to MCU. The communication adopts software simulation UART, with two I/O pins as RX
and TX. Communication rate is 4800bps, add start bit and stop, so every sending byte has 10
bits. Data is send according to frame format: frame head | every data | check sum. DSP will
transfer a frame every 100ms, and every sending will take about 15ms.
THEORY OF OPERATION
Pins Interface
Type
P24-P27
Preset switch CH 1, single digit
static
P20-P23
Preset switch CH 2, tens digit
static
P4-P7
Preset switch CH 1, single digit
static
P0-P3
Preset switch CH 1, tens digit
static
P10-P13 DSP
Interface
SPI
P14-P15 Remote
Modified
MIDI
P37/ADC7 B1 detection from AMP3 Out
Analog
P34
Power Amp Protection/Trouble
Static
P33
Power Supply Protection
Static
P30-P32
Interface to volume control chip
I
2
C
P44-P45
Power LED (red/green)
static
P43
Bass Sent detection from “Bass Line Out” static
Содержание Personalized Amplification System
Страница 3: ...3 THEORY OF OPERATION Figure 1 PS1 signal flow Diagram ...
Страница 44: ...44 APPENDIX CS5361 AD Converter Pinout and Table ...
Страница 45: ...45 APPENDIX CS8406 Digital Audio Interface Transmitter ...
Страница 46: ...46 APPENDIX CS8416 Digital Audio Interface Receiver ...
Страница 47: ...47 APPENDIX TDA8929T Digital Amplifier Controller ...
Страница 48: ...48 APPENDIX TDA8927J Digital Power Amplifier ...