[net.micro.cbm] Specs. for the MSD Disk Drives

paulw@amd.UUCP (Paul Woods) (07/27/84)

    Here are some of the features and the specifications for the MSD 
Disk Drives.


                        

**********************************************************************
                 Feature of the MSD SD-2 
**********************************************************************


Buffer meory capacity      6K

Complete Duplication Time (format, copy & verify a FULL DISK) 
                	   Less than 2 minutes!!   The 1541 takes
 			   about 30 to 40 minutes to do the same
			   operations when using two 1541's.

Format Time                 17 seconds (Note: to sense the last track
                            the MSD Disk Drive uses an optical sensor.)
  
                            The 1541 takes 1 minute 20 seconds to do this,
	                    plus a wack on your disk drives head to
                            tell it that it is at the last track.  This
                            has to be one of the greatest disk drive
                            design mistakes of all time! 

Serial Bus                  2 connectors

Parallel bus                IEEE

Daisychain                  Up to 4 SD-2's






**********************************************************************
                Actual Disk Drive Specifications
**********************************************************************


Total Capacity		174,848 bytes per diskette
Sequential		168,656 bytes per diskette
Relative		167,132 bytes per diskette
                         65,535 recors per file

Directory Entries       144 per diskette
Blocks                  683 total per diskette
                        664 available per diskette
Tracks			35 per diskette
Sectors			17 to 21 per track
Bytes			256 per sector
Diskettes		Standard 5 1/4", single sided single density

NOTE: The SD-2 contains two disk drive mechanisms and can therefore
      handle two times the above capacities (one per each diskette).




                      SOFTWARE

16K Bytes Operating System
4K RAM buffer area (6K for the SD-2)
Microprocessor based disk controller (6511Q)
Commodore Compatible Serial Bus Interfac
Commodore Compatible IEEE Parallel Bus Interface




                  Physical Dimensions

          SD-1                          SD-2

Height    6.2"                          6.2"
Width     4.2"                          5.9"
Depth    13.3"                         13.3"



                       INTERFACE

Dual Commodore compatible Serial Bus
Commodore compatible IEEE Parallel Bus
Jumper for selecting device number 8,9,10 or 11



                ELECTRICAL REQUIREMENTS

VOLTAGE                    110  or optional 220 VAC
Frequency                  60 or 50 Hz
Power                      50 watts









	I hope that all of this data is useful for some one who
is not sure whiether or not to purchase the MSD disk drive. For me
I am awaiting a reply to my previous letter asking for comments to
the use of these Disk Drives by those who currently own them before 
I go out to purchase a SD-2 for myself.


Paul Woods
Advanced Micro Devices, Inc.
901 Thompson Place 
Sunnyvale, CA.  94088
M/S #6