ALESIS HR-16 - Manual (Page 6)

HR-16/HR16B Service Manual 1.00 vi 03/31/06
TABLE OF CONTENTS
PREFACE..................................................................................................... ii
READ THIS! ................................................................................................. ii
WARNINGS.................................................................................................. iii
SAFETY SUGGESTIONS ............................................................................ iv
General Troubleshooting.............................................................................. v
1.0 General Description ............................................................................... 1
1.1 Main PC Board Revisions ................................................. 1
2.0 Power Supply ......................................................................................... 1
2.1 Battery Backup .................................................................. 2
2.2 PUP Circuit ........................................................................ 2
3.0 The 8031 ................................................................................................ 3
3.1 Reset ................................................................................. 3
3.2 Memory Mapped I/O.......................................................... 4
3.3 Keypad I/O......................................................................... 4
3.4 MIDI I/O ............................................................................. 4
4.0 DM3AG ASIC ......................................................................................... 5
4.1 Mask ROMs....................................................................... 5
5.0 Analog Signal Paths ............................................................................... 6
5.1 Drum Signal Output ........................................................... 6
5.2 Piezo/Data Slider Input...................................................... 6
5.3 Tape I/O............................................................................. 6
5.4 Tape Output....................................................................... 7
5.5 Tape Input ......................................................................... 7
6.0 Test Procedures ..................................................................................... 7
6.1 General Testing ................................................................. 8
6.2 Internal Diagnostics and Hidden Keys .............................. 8
6.3 DAC Adjustments .............................................................. 8
7.0 Updates and Corrections ....................................................................... 9
7.1 New SRAM Supply Circuit................................................. 9
7.2 Glass Zener (D15)............................................................. 9
7.3 Dirty Cliff jacks................................................................... 10
7.4 Ground CE......................................................................... 10
7.5 RF resistor ......................................................................... 10
7.6 10K MIDI Resistor (R5) ..................................................... 11
7.7 MIDI Pullup ........................................................................ 11
7.8 RF Shields ......................................................................... 11
7.9 LCD Contrast Adjustments................................................ 11
7.10 DAC Drift ......................................................................... 12
7.11 Old Keypad PC Boards ................................................... 12
7.12 Lifting R41 ....................................................................... 12
7.13 Reset Capacitor............................................................... 12
7.14 Sram Capacitor ............................................................... 12
7.15 Tape Capacitors .............................................................. 13
7.16 RF chokes ....................................................................... 13
7.17 AQ reset threshold .......................................................... 13
7.18 AQ R116.......................................................................... 13
7.19 Volume Slider Wiring....................................................... 13
7.20 PUP Capacitor................................................................. 14
8.0 Common Solutions ................................................................................. 15
9.0 Service Parts List ................................................................................... 18
10.0 Software History ................................................................................... 20
11.0 MIDI Implementation ............................................................................ 23
12.0 Service Manual History ........................................................................ 31
INDEX........................................................................................................... 32