And we can represent numbers of any size:

                     11110000                F0             240
                     11111111                FF             255
                    100000000               100             256
                1111111111111              IFFF            8191
            11101000101011010             1D15A           119130

          And so on. It is common to see a '$' sign affixed to a
      hexadecimal number so that the reader will not take it to be
      an ordinary decimal quantity. Or sometimes a following 'h'
      does the same thing. So $1234 or 2345h are to be considered
      hexadecimal numbers. In this manual, all numbers are in
      'HEX' unless specifically stated otherwise.

      EPROM's

          Now, consider for a moment the diagram of Figure 1. It
      shows the 'pinout' of several commonly used EPROM'S. In use,
      the pins marked O0 through O7 are connected to the data bus.
      The EPROM, when enabled to do so, outputs data on these pins.
      Since there are eight output pins, the EPROM can output an
      entire byte at a time. An EPROM is a 'byte-wide' device.
          The pins marked A0 through A15 are address pins. The
      computer imposes a binary address on these pins to specify
      which-location in the EPROM the data is to come from. The
      lowest address is, of course, $0000- all address lines low.
      The highest EPROM address depends on how many address pins
      there are. The capacity of an EPROM Is usually specified as
      a certain number of 'KILOBYTES'. A kilobyte is two to the
      10th power or $400 bytes. (1024 decimal).  A '1k' EPROM like
      the 2758 must therefore have 10 address pins. The following
      table gives the maximum EPROM address for several common
      types.

              TYPE      CAPACITY     HIGHEST ADDRESS

              2758         1k                3FF
              2716         2k                7FF
              2732         4k                FFF
              2764         8k               1FFF
             27128         16k              3FFF
             27256         32k              7FFF
             27512         64k              FFFF

         When the PROMENADE programs an EPROM, the desired EPROM
     address is applied to the address pins, the data to be
     programmed into the EPROM at that address is applied to the
     data pins, and various signals and voltages are applied to
     other pins as required.


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