Lexicon MPX 110 Service Manual page 6

MPX 110 Service Manual
ADC Pot Test (7) ....................................................................................................................... 5-11
EEPROM Checksum (8)............................................................................................................. 5-12
MIDI Tests (9)............................................................................................................................ 5-13
LED Test (10) ............................................................................................................................ 5-14
Lexichip3 External DRAM Test (11)............................................................................................. 5-14
Burn In Loop (12)....................................................................................................................... 5-15
Audio I/O (13) ............................................................................................................................ 5-16
Exit Diagnostics (14) .................................................................................................................. 5-16
Initialize (15).............................................................................................................................. 5-16
Restoring Factory Settings ............................................................................................................. 5-16
Disassembly/Reassembly .............................................................................................................. 5-17
Disassemby............................................................................................................................... 5-17
Reassembly .............................................................................................................................. 5-17
Removal and installation of components...................................................................................... 5-17
Chapter 6 Theory of Operation ......................................................................6-1
Sheet 1: .......................................................................................................................................... 6-1
Input Stage.................................................................................................................................. 6-1
Output Stage............................................................................................................................... 6-1
Sheet 2........................................................................................................................................... 6-2
Single-ended to differential converter ............................................................................................ 6-2
AK4528 CODEC.......................................................................................................................... 6-2
Differential to Single-Ended Output Amplifiers................................................................................ 6-3
Sheet 3........................................................................................................................................... 6-3
L3 Initialization............................................................................................................................. 6-3
Audio Memory ............................................................................................................................. 6-4
Master Clock Generator ............................................................................................................... 6-4
I/O .............................................................................................................................................. 6-4
SEEPROM .................................................................................................................................. 6-4
Z80 Memory Management............................................................................................................ 6-5
Clocks......................................................................................................................................... 6-5
DSP............................................................................................................................................ 6-5
Z80 RESET................................................................................................................................. 6-5
Sheet 5........................................................................................................................................... 6-6
Encoders..................................................................................................................................... 6-6
Sheet 6........................................................................................................................................... 6-6
Control Input (IAD) ....................................................................................................................... 6-6
Sheet 7: .......................................................................................................................................... 6-6
Footswitch................................................................................................................................... 6-6
LED/Switch Matrix........................................................................................................................ 6-6
Sheet 8: .......................................................................................................................................... 6-7
Power Fail/Reset ......................................................................................................................... 6-7
MIDI I/O ...................................................................................................................................... 6-7
S/PDIF Out .................................................................................................................................. 6-7
Chapter 7 Parts List........................................................................................7-1
MPX110 MAIN BOARD ASSEMBLY................................................................................................. 7-1
MPX110 MECHANICAL ASSEMBLY ................................................................................................ 7-2
MPX110 SHIP/PACKAGING MATERIAL........................................................................................... 7-3
MPX110 TRANSFORMER OPTIONS ............................................................................................... 7-3
Chapter 8 Schematics and Drawings ............................................................8-1
Schematics:.................................................................................................................................... 8-1
Drawings: ....................................................................................................................................... 8-1