NEC uPD371 Magnetic Tape Controller Jun77 free download

File name uPD371_Magnetic_Tape_Controller_Jun77.pdf

NEe mlcrocomputers,lnc. /JPD371 MAGNETIC TAPE CASSETTE/CARTRIDGE CONTROLLER USERS' MANUAL Five Milita Drive/Lexington, Massachusetts 02173 Telephone (617) 862-6410 Telex 92--3434 TWX 710-326-6520 NEC MICROCOMPUTERS, INC. uPD371 MAGNETIC TAPE CASSETTE/CARTRIDGE USERS' MANUAL June 9, 1977 The NEC uPD37l is a high performance N-Channel LSI tape cassette/cartridge controller designed to interface between most cassette or cartridge tape drives and most microprocessors or minicomputers. FEATURES - Compatible with ANSI, ECMA and ISO standards - Also compatible with most other standards - Hardware CRC generation and verification - Read after write capability - High speed file search - Multiple drive capability - May read or write on one drive while rewinding or file searching on another - Maximum Data Transfer rate of 375K bits/sec equivalent to 468 IPS at 800 BPI 2 TABLE OF CONTENTS INTRODUCTION 4 INPUT/OUTPUT SIGNALS 7 INTRODUCTION 7 PROCESSOR INTERFACE 7 TAPE DRIVE INTERFACE 14 ADDRESSABLE INTERNAL REGISTERS 17 INTRODUCTION 17 WRITE REGISTERS 17 READ REGISTERS 27 TAPE CASSETTE/CARTRIDGE CONTROLLER EXAMPLES 32 PROCESSOR INTERFACE 32 TIMING 32 TAPE DRIVE INTERFACE 35 Single Drive 35 Multiple Drive Systems 36 SOFTWARE 39 Introduction 39 Other Formats 39 High Speed File Search 40 Parameters and Conventions 40 Listings of Drive Handling Routines 42 uPD37l SPECIFICATIONS 52 3 INTRODUCTION The uPD371 uses the ANSI, ECMA and 180* standard recording technique of "bi-phase-level encoding". The name is usually shortened to "phase encoding". In phase encoding a logic one is encoded as a positive transition. A logic zero is encoded as a negative transition. These data transitions are made to occur at intervals with a constant period. Halfway between data transitions, a "phase" transition may be required to establish the proper polarity for the succeeding data transition. An example of phase encoded data is shown in Lin