50 IFPEEK(165)=255THEN4000:REM REPORT PROGRAMMING ERROR.
   60 PRINT"PROGRAMMING OK."
   70 V:REM VERIFY ONCE AGAIN.
   80 IFPEEK(165)=255THEN4020:REM REPORT VERIFY ERROR.
   90 PRINT"VERIFY OK.":ETC, ETC....

   SETTING UP A RAM BUFFER

       Let's say you're using a 64 mode BASIC application
   program and you want to set aside a large RAM buffer for
   moving data to and from EPROM's and disk that you're sure
   BASIC will not intrude upon. Here's a suggestion. Early In
   your program, execute the following BASIC statement:

   10 POKE55,0:POKE56,64:CLR

   This confines your BASIC program to the 14k from 0801 through
   3FFF.  Now, you have 32k from 4000 through BFFF for your RAM
   buffer; and 8k from C000 through DFFF to use as a utility
   area for ML programs, etc.

   ONE FURTHER IMPORTANT POINT

       A decimal address of 32768 must become a negative number
   when expressed as a numeric variable.  This number will
   decrease to -1 at 65535. This is of concern only for
   addresses above 7FFF. Examination of the following table
   will give you an idea of how to handle this.

         DESIRED        DECIMAL VALUE        NUMERIC VARIABLE
       HEX ADDRESS        EQUIVALENT            EQUILAVENT

           1000              4096                    4096
           2000              8192                    8192
           4000             16384                   16384
           7FFF             32767                   32767
           8000             32768                  -32768
           8FFF             36863                  -32673
           9000             36864                  -32672
           9FFF             40959                  -24577
           A000             40960                  -24576
           AFFF             45055                  -20481
           B000             45056                  -20480
           BFFF             49151                  -16385
           C000             49152                  -16384
           CFFF             53247                  -12289
           D000             57248                  -12288
           DFFF             57343                   -8193


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