摘要:
A system for allowing a two word jump instruction to be executed in the same number of cycles as a single word jump instruction, thereby allowing a processor system to increase memory space without reducing performance. A first address bus is coupled to the linearized program memory for sending addresses of instructions to be fetched to a linearized program memory. A pointer is coupled to the first address bus for storing an address location of a current instruction in the linearized program memory to be fetched and for placing the address location of the current instruction to be fetched on the first address bus. A second address bus is provided and has one end coupled to the output of the program memory and a second end coupled to the first address bus. The second address bus is used for placing an address of an operand of a second word of the two word jump instruction onto the first address bus after an address of an operand of a first word of the two word jump instruction has been placed on the first address bus. This allows the addresses of the first word and the second word to be combined to provide the full address value of the two word jump instruction in the same number of cycles as a single word jump instruction.
摘要:
An instruction set for a microcontroller which has robust multiple word instructions. The instruction set has a plurality of instructions wherein the plurality of instructions comprises single word instructions and multiple word instructions. At least one bit is located in a predetermined location in all non-first words of all multiple word instructions. The bit will be decoded by the microcontroller as no operation bit if the first word of the multiple word instruction is not executed prior to execution of any succeeding words in the multiple word instruction.
摘要:
A system for allowing a two word jump instruction to be executed in the same number of cycles as a single word jump instruction, thereby allowing a processor system to increase memory space without reducing performance. A first address bus is coupled to the linearized program memory for sending addresses of instructions to be fetched to a linearized program memory. A pointer is coupled to the first address bus for storing an address location of a current instruction in the linearized program memory to be fetched and for placing the address location of the current instruction to be fetched on the first address bus. A second address bus is provided and has one end coupled to the output of the program memory and a second end coupled to the first address bus. The second address bus is used for placing an address of an operand of a second word of the two word jump instruction onto the first address bus after an address of an operand of a first word of the two word jump instruction has been placed on the first address bus. This allows the addresses of the first word and the second word to be combined to provide the full address value of the two word jump instruction in the same number of cycles as a single word jump instruction.
摘要:
A data pointer for generating an indirect addressing mode address within a single cycle for a selected one of a plurality of multiple indirect addressing modes. The data pointer is used with a processor architecture scheme which allows for encoding of multiple addressing modes. A data pointer register is coupled to the processor architecture scheme for storing a current address of an operand to be used in a simple indirect addressing mode. An incrementer is coupled to the data pointer register for incrementing the current address of an operand to be used in a simple indirect data addressing mode by a set number thereby generating an address of an operand to be used in an indirect addressing mode with auto preincrement. An adder is coupled to the data pointer register for combining the current address of an operand to be used in a simple indirect data addressing mode with an offset number thereby generating an address of an operand to be used in an indirect addressing mode with offset. A multiplexer circuit is coupled to an output of the data pointer register, to an output of the incrementer, and to an output of the adder for selecting a desired indirect addressing mode address.
摘要:
A cache module for a central processing unit has a cache control unit with an interface for a memory, a cache memory coupled with the control unit, wherein the cache memory has a plurality of cache lines, at least one cache line of the plurality of cache lines has an address tag bit field and an associated storage area for storing instructions or data, wherein the address tag bit field is readable and writeable and wherein the cache control unit is operable upon detecting that an address has been written to the address tag bit field to initiate a preload function in which instructions or data from the memory are loaded from the address into the at least one cache line.
摘要:
A microcontroller has a random access memory, and a Controller Area Network (CAN) controller with a control unit receiving an assembled CAN message. The control unit generates a buffer descriptor table entry using the assembled CAN message and stores the buffer descriptor table entry in the random access memory, and the buffer descriptor table entry has at least a message identifier and load data from the CAN message and information of a following buffer descriptor table entry.
摘要:
A special mode key match comparison module has N-storage elements and a special mode key match comparator. The N-storage elements accumulate a serial data stream, and then determine whether a digital device should operate in a normal user mode, in a public programming mode, or in a particular private test mode. To reduce the possibility of accidentally decoding a false test or programming mode, the data stream has a sufficiently large number of N-bits to substantially reduce the probability of a false decode. To further reduce the possibility of accidentally decoding a programming or test mode, the special mode key match comparison module may be reset if less or more than N-clocks are detected during the accumulation of the N-bit serial data stream. The special mode key match data patterns may represent a normal user mode, a public programming mode, and particular private manufacturer test modes.
摘要:
A cache module for a central processing unit has a cache control unit with an interface for a memory, a cache memory coupled with the control unit, wherein the cache memory has a plurality of cache lines, at least one cache line of the plurality of cache lines has an address tag bit field and an associated storage area for storing instructions or data, wherein the address tag bit field is readable and writeable and wherein the cache control unit is operable upon detecting that an address has been written to the address tag bit field to initiate a preload function in which instructions or data from the memory are loaded from the address into the at least one cache line.
摘要:
An electronic circuit includes a non-volatile memory on an integrated circuit that has several memory cells. The cells each have a voltage state and a gate. A gate bias circuit on the integrated circuit is coupled to the gates of the memory cells. The gate bias circuit includes at least a read voltage and a margin voltage. A detection circuit on the integrated circuit is coupled to the cells. The detection circuit includes a comparator and a reference voltage. The reference voltage and the voltage state of one of the cells are coupled to the comparator. The detection circuit includes an output generating a signal corresponding to the comparator output. The integrated circuit includes a monitor circuit. The monitor circuit is coupled to the output of the detection circuit and determines whether the voltage state of the cell transitions between application of the read and margin voltages to the gate.
摘要:
A system for powering down configuration circuits to minimize power consumption has at least one first configuration circuit for configuring a peripheral module. A second configuration circuit is coupled to the peripheral module and to the at least one first configuration circuit. The second configuration circuit is used for enabling and disabling the peripheral module. The second configuration circuit is further used to power down the at least one first configuration circuit to minimize current consumption of the at least one first configuration circuit when the peripheral module is disabled.