Fixed Binary Signed (p <= 7)

Fixed Binary (p <= 7) is an 8-bit, signed, 2's complement binary integer by default. The low order 7 bits contain the integer, the high order bit contains the sign. The sign bit (S) is 1 if the value is negative, 0 if the value is positive or zero. Use the -fb7asfb15 option to provide compatibility with previous versions of Open PL/I.