example, we are telling the PROMENADE to read a 27256 into
   computer RAM from 5000 through BFFF, beginning at EPROM
   address 1000. E6 is the control word for a 27256 programming
   at 12.5 volts.

   CHECKSUMS and HASHTOTALS

       When you execute the READ command as in the examples
   above, you will notice that a 'CHECKSUM' and a 'HASHTOTAL' is
   printed on the screen as soon as the operation is completed.
   The CHECKSUM is the low-order byte of the arithmetic sum of
   all the data bytes read from the EPROM. The HASHTOTAL is the
   result of exclusive-or ing all bytes read with each other.
   These numbers can serve as a quick means of identification of
   an EPROM, or as a means of checking the validity of the data
   itself.

   WHERE TO PUT THE DATA

       Notice that the READ command gives you complete freedom:
   you can read as many bytes from the EPROM as you want,
   starting anywhere on the chip, and in principle you can put
   them anywhere in computer memory. As a practical matter,
   certain areas of computer RAM are off-limits because your
   computer must use then for its own purposes. If your read
   command overwrites these areas, the computer will crash.
       Consider first the COMMODORE 64 or the 128 in 64 MODE:
   if you are not running a BASIC program, then you are free to
   use computer RAM from 0800 through DFFF. A BASIC program
   ordinarily resides in RAM starting at 0801. In a later
   section we discuss the matter of using PROMOS commands in a
   BASIC application program.
       In the case of the COMMODORE 128 in 128 MODE, we need to
   consider a special PROMOS command which pertains only to the
   128, the bank select command.

   The B COMMAND- Select PROMOS RAM bank. (128 mode command.)

       This command selects the computer RAM bank, 0 or 1, which
   will be used for subsequent PROMOS operations.  Example:

      B1

      Execution of this command causes PROMOS to use bank 1
   RAM, PROVIDED the RAM involved lies in the range 2000 through
   DFFF.  Outside this range, bank 0 RAM will be used.
      Using this command does not in any way affect the BASIC
   7.0 'BANK' command.  PROMOS bank 1 will remain in use until
   you switch back to PROMOS bank 0.  To do this, execute either


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