摘要:
A data processing system (10) performs indexed addressing, autoincrementing, and autodecrementing using power of two byte boundaries. For example, a 5-bit offset allows a user to progress sixteen bytes either forward or backward through a table of data. An instruction specifying an operation to be performed, a pointer register (58, 60), and an offset value is provided to an execution unit (14). The pointer register (58, 60) stores a first address value and the offset value has a sign and a magnitude. An arithmetic logic unit, ALU, (52) inverts the sign of the offset value to provide an inverted sign value. A plurality of adders (100, 102, 104, 106, and 108) adds the offset value, the first address value, and the inverted sign value to generate an offset sum. A positive offset value is increased by one to generate a symmetric power of two offset range.
摘要:
A circuit (14) and method which determine a degree of membership of an input in a membership set during a fuzzy logic operation. The degree of membership is calculated by a single "MEM" software instruction. The MEM instruction determines whether the system input has a degree of membership of zero, of a saturation level, or of some value in between. An operand assignment circuit (50) and an ALU (56) allow circuit (14) to determine the degree of membership more quickly. Assignment circuit (50) determines a multiplier for a multiplication operation based on a number of significant bits in the values to be multiplied. If the multiplier is smaller than the multiplicand, shorter multiplication operations may be performed. Additionally, ALU (56) operates in a split mode of operation which is able to perform two eight bit subtraction or multiplication operations concurrently which also results in these operations being performed more efficiently.
摘要:
A circuit (14) to evaluate a plurality of fuzzy logic rules in a data processor (10) in response to a single "REV" software instruction. The REV instruction evaluates the rules stored in a memory (32) to determine a rule strength of each. Antecedents are separated from consequences of each of the rules by a buffer address. To evaluate the antecedents, an ALU (52) subtracts an antecedent in memory (32) from a current antecedent stored in an accumulator (58). Subsequently, a swap logic (46) provides control information to assign a minimum value as a rule strength of the rule. Similarly, a maximum rule strength is required during evaluation of the consequences. ALU (52) subtracts a consequence in memory (32) from a consequence stored in accumulator (58). Depending on a result, swap logic (46) provides control information to assign a maximum rule strength to the consequences of the evaluated rule.
摘要:
A circuit (14) and method which determine a degree of membership of an input in a membership set during a fuzzy logic operation. The degree of membership is calculated by a single "MEM" software instruction. The MEM instruction determines whether the system input has a degree of membership of zero, of a saturation level, or of some value in between. If a membership function has a boundary with an infinite slope, the slope value is set equal to zero and the degree of membership is then set equal to a saturation value for those input values corresponding to the infinite slope boundary.
摘要:
An adder circuit that has an encoded carry input, where a bit position weight of the carry input is two, allows the adder circuit to selectively concurrently add a data value of two to a first and a second input data operand of the adder circuit. The adder circuit is also able to add the first and second input data operands with a second carry input that is not encoded. A recoded multiplier combines two partial product calculations into one calculation during only a first partial product calculation operation by using the adder circuit. Partial product calculations are reduced in number during a multiply operation of a data processor.
摘要:
An adder circuit that has an encoded carry input, where a bit position weight of the carry input is two, allows the adder circuit to selectively concurrently add a data value of two to a first and a second input data operand of the adder circuit. The adder circuit is also able to add the first and second input data operands with a second carry input that is not encoded. A recoded multiplier combines two partial product calculations into one calculation during only a first partial product calculation operation by using the adder circuit. Partial product calculations are reduced in number during a multiply operation of a data processor.
摘要:
In a data processing system (10) implementing a fuzzy logic operation, a switching mechanism (802) is implemented to provide a selection between a variable format rule base (803) and a fixed format rule base. The variable format rule base utilizes buffers between fuzzy input addresses and fuzzy output addresses, while the fixed format rule base does not require such buffers since a number of fuzzy input addresses and fuzzy output addresses is predetermined.
摘要:
A circuit (14) to evaluate a plurality of fuzzy logic rules as executable instructions in a data processor (310). A first instruction retrieves a fuzzy input value from memory (32) and stores it in an accumulator (58). A second instruction retrieves a second fuzzy input value from memory (32) and compares it to the fuzzy input value stored in the accumulator (58). The minimum value of the two fuzzy input values is then allowed to remain in the accumulator (58). Another program instruction retrieves a fuzzy output value from memory (32) and compares it to the value in the accumulator (58). The maximum of these two values is then determined by the instruction and this maximum value is then stored in memory (32).
摘要:
A circuit (14) and method which determine a degree of membership of an input in a membership set during a fuzzy logic operation. The degree of membership is calculated by a single "MEM" software instruction. The MEM instruction determines whether the system input has a degree of membership of zero, of a saturation level, or of some value in between. If a membership function has a boundary with an infinite slope, the slope value is set equal to zero and the degree of membership is then set equal to a saturation value for those input values corresponding to the infinite slope boundary.
摘要:
The data processing system(10) implements a resumable instruction using two instruction bytes. When a program counter (72) points to a first instruction byte, a first data processing operation is initiated. If an interrupt occurs during execution of the first data processing operation, intermediate data calculations held in a plurality of temporary registers (64, 66, 68) are saved in stack memory at a location pointed to by the stack pointer register (72). The program counter is incremented to point to a second byte of the instruction. An instruction resume operation is executed and the intermediate results of the data processing operation are accessed from the stack memory and restored to respective storage locations within the data processing system. After the intermediate results are restored, the program counter is decremented to point to the first instruction byte and the instruction continues executing the data processing operation as though no interrupt occurred.