PREFACE..................................................................................................... ii
READ THIS! ................................................................................................. ii
WARNINGS.................................................................................................. iii
SAFETY SUGGESTIONS ............................................................................ iv
2.0 Power Supply ......................................................................................... 1
3.0 The 8031 ................................................................................................ 3
4.0 DM3AG ASIC ......................................................................................... 5
6.0 Test Procedures ..................................................................................... 7
8.0 Common Solutions ................................................................................. 15
10.0 Software History ................................................................................... 20
INDEX........................................................................................................... 32
HR-16/HR16B Service Manual 1.00
TABLE OF CONTENTS
2.2 PUP Circuit ........................................................................ 2
3.1 Reset ................................................................................. 3
3.3 Keypad I/O......................................................................... 4
3.4 MIDI I/O ............................................................................. 4
4.1 Mask ROMs....................................................................... 5
5.3 Tape I/O............................................................................. 6
5.4 Tape Output....................................................................... 7
5.5 Tape Input ......................................................................... 7
7.4 Ground CE......................................................................... 10
7.5 RF resistor ......................................................................... 10
7.7 MIDI Pullup ........................................................................ 11
7.8 RF Shields ......................................................................... 11
7.10 DAC Drift ......................................................................... 12
7.12 Lifting R41 ....................................................................... 12
7.16 RF chokes ....................................................................... 13
7.18 AQ R116.......................................................................... 13
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03/31/06