浮動小数点数
Floating point is implemented in software using "programmed operators", except on the SDS 9300 which has hardware floating point. All floating point numbers are stored as 48-bit double words. Single precision has a 24-bit signed fraction and a 9-bit signed exponent, double precision has a 39-bit fraction and a 9-bit exponent. Both the exponent and the fraction are stored in big-endian twos-complement format. The binary point is assumed to be immediately left of the high-order bit of the fraction. The value of the number is codice_1, where F is the fraction and E is the exponent.