摘要 |
A microprogram controlled microprocessor capable of normalizing a given data in a floating point representation includes a memory storing a microprogram, an address register for holding a microprogram start address, an operand register for holding a source operand, a temporary register for temporarily holding an operation data, a pointer for holding a code indicative of the operand register at the time of starting the microprogram and for indicating a transfer source register in a transfer operation between internal registers, and a discriminator for discriminating whether or not an input source operand is a normalized number. The microprocessor operates on the basis of the microprogram to execute a given operation to the input source operand while causing the discriminator to discriminate whether or not the input source operand is a normalized number, so that the microprogram is completed without a branch when the input source operand is a normalized number. On the other hand, when the input source operand is an unnormalized number, the microprocessor operates to branch to a normalizing program and to cause a normalized operand to be held in the temporary register and a code indicative of the temporary register to be set to the pointer. In addition, the microprocessor operates to re-execute the microprogram from the address designated by the address register. |