NEC uPD372 Floppy Disk Controller Mar77 free download

File name uPD372_Floppy_Disk_Controller_Mar77.pdf

N'ECm Inc. J.LPD372 FLOPPY DISK CONTROLLER USERS' MANUAL Five Militia Drive/Lexington, Massachusetts 02173 Telephone (617) 862-6410 Telex 92-3434 Rev/2 NEC MICROCOMPUTERS, INC. uPD372D LSI FLOPPY DISK CONTROLLER CHIP USERS' MANUAL March 11, 1977 The NEC uPD372D is a high performance N-channel LSI floppy disk controller designed to- interface between most minicomputers or microprocessors and most floppy disk drives. The uPD372D is the most versatile floppy disk controller chip available. FEATURES - Compatible with IBM3740 format - Compatible with Shugart Minifloppy format - Compatible with many other formats - Generates and checks Cyclic Redundancy Characters - Initiates operations at address marks or physical index - Formats clear disks - Handles up to four floppy disk drives - Can read or write on one drive while simultaneously track seeking on another - Track stepping rate and step pulse width are programmable - Sector size programmable from one byte to one sector per track - Data transfer rate easily changed - Standard power supply voltages +12V, +5V, -5V The uPD372D is compatible with most floppy disk drives including: Calcomp 140 Pertec FD400 CDC BR803 Potter DD4740 GSI 050 Remex RFS7400 GSI 110 Shugart SA400 Innovex 210 Shugart SA900 Orbis 74 Sycor 145 Persci 75 2 TABLE OF CONTENTS INTRODUCTION 4 INPUT/OUTPUT SIGNALS 6 INTRODUCTION 6 PROCESSOR INTERFACE 6 DISK DRIVE INTERFACE 9 ADDRESSABLE INTERNAL REGISTERS 12 INTRODUCTION 12 WRITE REGISTERS 14 READ REGISTERS 22 DATA CONDITIONER 26 INTRODUCTION 26 DATA CONDITIONER EXAMPLE 30 FLOPPY DISK CONTROLLER EXAMPLE 32 HARDWARE 32 SOFTWARE 35 uPD372 SPECIFICATIONS 65 3 INTRODUCTION The uPD372 may be interfaced directly to a host processor as shown in Figure 1 or it may be interfaced to a controller processor which in turn is interfaced to the host processor as shown in Figure 2. Most processors interfaced to the uPD372 must, when reading from or writing a record on the disk, be completely dedicated to the task of controlling the disk drive(s). These periods may last several millis