US 6,097,988 A · Logic system and method employing multiple configurable logic blocks and capable of implementing a state machine using a minimum amount of configurable logic

Abstract

A logic system is presented including multiple configurable logic blocks (CLBs) implementing a state machine having multiple states, each state being associated with one or more logic functions and one or more possible next states. Each CLB includes programmable logic circuitry, and is configurable to implement the logic functions required in any given state. A complex state machine may be implemented using only 1+s CLBs, where s is the maximum number of next states of any state, thereby using a minimum amount of configurable logic. The logic system also includes a memory unit, a control unit coupled to the memory unit and to each of the CLBs, and an interface unit coupled to the control unit and to each of the CLBs. The memory unit stores configuration data required to configure the CLBs and state transition information. The control unit generates and stores current state information. Following programming, a single "active" CLB implements the logic functions required in the current state. The remaining CLBs are "inactive". While in the current state, the control unit uses state transition information from the memory unit and current state information to determine the possible next states. The control unit then retrieves configuration data from the memory unit corresponding to each of the possible next states, and programs one inactive CLB for each possible next state. The interface unit routes input signals to, and output signals from, the active CLB in response to a control signal from the control unit.

Claims21

Dependent claims

A logic system for implementing a state machine, wherein the state machine comprises a plurality of states, and wherein each of the plurality of states has one or more possible next states which may be reached by a single state transition, the logic system comprising:

a control unit configured to produce configuration signals;
and
a plurality of configurable logic blocks (CLBs) coupled to the control unit, wherein each of the plurality of CLBs is configurable to perform one or more selected logic functions in response to the configuration signals;
wherein when the state machine is in a given state:
one of the plurality of CLBs is "active", wherein the active CLB is coupled to receive a plurality of input signals and performs one or more logic functions associated with the state in order to produce a plurality of output signals;
and
the control unit provides configuration signals to a number of the remaining CLBs equal to the number of possible next states in order to configure each of the number of the remaining CLBs to perform one or more logic functions associated with one of the one or more possible next states.

4 more elements

a memory unit configured to store configuration data;
a control unit coupled to the memory unit and configured to retrieve the configuration data from the memory unit and to produce configuration signals, wherein the configuration signals comprise the configuration data;
a plurality of configurable logic blocks (CLBs) coupled to the control unit, wherein each of the plurality of CLBs is configurable to perform one or more logic functions in response to the configuration signals;
and
an interface unit coupled to the control unit and to each of the plurality of CLBs, wherein the interface unit is configured to route a plurality of input signals to, and a plurality of output signals from, one of the plurality of CLBs in response to a control signal from the control unit;
wherein when the state machine is in a given state:
one of the plurality of CLBs is "active", wherein the interface unit routes the plurality of input signals to the active CLB, and wherein the active CLB performs one or more logic functions associated with the state in order to produce the plurality of output signals, and wherein the interface unit routes the plurality of output signals from the active CLB;
and
the control unit provides configuration signals to a number of the remaining CLBs equal to the number of possible next states in order to configure each of the number of the remaining CLBs to perform one or more logic functions associated with one of the one or more possible next states.

6 more elements

A logic device formed upon a single monolithic semiconductor substrate for implementing a state machine, wherein the state machine comprises a plurality of states, and wherein each of the plurality of states has one or more possible next states which may be reached by a single state transition, the logic device comprising:

a memory unit configured to store configuration data;
a control unit coupled to the memory unit and configured to retrieve the configuration data from the memory unit and to produce configuration signals, wherein the configuration signals comprise the configuration data;
and
a plurality of configurable logic blocks (CLBs) coupled to the control unit, wherein each of the plurality of CLBs is configurable to perform one or more logic functions in response to the configuration signals;
a plurality of I/O pads for receiving a plurality of input signals and providing a plurality of output signals;
and
an interface unit coupled to the control unit, to each of the plurality of I/O pads, and to each of the plurality of CLBs, wherein the interface unit is configured to form a plurality of signals paths between the plurality of I/O pads and one of the plurality of CLBs in response to a control signal from the control unit;
wherein when the state machine is in a given state:
one of the plurality of CLBs is "active", wherein the interface unit routes the plurality of input signals from the plurality of I/O pads to the active CLB, and wherein the active CLB performs one or more logic functions associated with the state in order to produce the plurality of output signals, and wherein the interface unit routes the plurality of output signals from the active CLB to the plurality of I/O pads;
and
the control unit provides configuration signals to a number of the remaining CLBs equal to the number of possible next states in order to configure each of the number of the remaining CLBs to perform one or more logic functions associated with one of the one or more possible next states.

8 more elements

Dependencies are inferred from the claim text.

Logic system and method employing multiple configurable logic blocks and capable of implementing a state machine using a minimum amount of configurable logic

Life of this patent

Logic system and method employing multiple configurable logic blocks and capable of implementing a state machine using a minimum amount of configurable logic

Life of this patent

Abstract

Claims21