Macintosh 128K and 512K: Data transfer and processing rates


The following article provides information on data transfer and processing
rates for the Macintosh 128K and Macintosh 512K.


Following are the data transfer rates for the Macintosh:

 Serial Port (external):

   AppleTalk:         230.4K baud
   Asynchronous:      57.6K baud (maximum rate)
   Synchronous:       920K baud (maximum rate with external clock)

 Disk Drive Port:  500K baud

 68000 Processor Access Rates (internal):

   ROM at: 8 MHz
   RAM at: 6 MHz

NOTE: The BlockMove Routine in ROM allows you to move blocks of data from
     one location of memory to another at ROM speed (8 MHz).  Otherwise, the
     normal RAM transfer rate is 6 MHz.

 Processing Data Rate

   13.3 megabits per second

NOTE: This rate is calculated using the definition in Federal Register,
     Volume 49 Number 252, page 50619.

Refer to the Motorola 68000 User's Manual for address calculation times as
well as for processing and instruction execution times.



Published Date: Feb 19, 2012