A 3D NAND memory device is provided in which control is performed by two microcontroller units (MCU). During manufacture of the memory device, bug fixes required for the controller may be addressed using a software solution by which an instruction requiring correction in one of the two MCUs is replaced with a corrected instruction stored in a RAM.

A memory device in accordance with a described method of operation includes a read only memory (ROM) address controller and a suspend signal generator. The ROM address controller is configured to sequentially output a plurality of operation ROM addresses at which ROM codes to be executed in response to an operation command are stored, and to suspend output of the plurality of operation ROM addresses in response to a suspend signal. The suspend signal generator is configured to generate the suspend signal that is activated during a preset period depending on whether a suspend ROM address is identical to an operation ROM address, among the plurality of operation ROM addresses, currently being output. The suspend ROM address is an address at which a ROM code, execution of which is to be suspended, among the ROM codes, is stored.

Processing circuitry performs data processing operations in response to instructions fetched from a cache or memory or micro-operations decoded from the instructions. Sampling circuitry selects a subset of instructions or micro-operations as sampled operations to be profiled. Profiling circuitry captures, in response to processing of an instruction or micro-operation selected as a sampled operation, a sample record specifying an operation type of the sampled operation and information about behaviour of the sampled operation which is directly attributed to the sampled operation. The profiling circuitry can include, in the sample record for a sampled operation corresponding to a given instruction, a reference instruction address indicator indicative of an address of a reference instruction appearing earlier or later in program order than the given instruction, for which control flow is sequential between any instructions occurring between the reference instruction and the given instruction in program order.

The present disclosure includes apparatuses and methods related to microcode instructions indicating instruction types. One example apparatus comprises a memory storing a set of microcode instructions. Each microcode instruction of the set can comprise a first field comprising a number of control data units, and a second field comprising a number of type select data units. Each microcode instruction of the set can have a particular instruction type defined by a value of the number of type select data units, and particular functions corresponding to the number of control data units are variable based on the particular instruction type.

The present disclosure includes apparatuses and methods related to microcode instructions indicating instruction types. One example apparatus comprises a memory storing a set of microcode instructions. Each microcode instruction of the set can comprise a first field comprising a number of control data units, and a second field comprising a number of type select data units. Each microcode instruction of the set can have a particular instruction type defined by a value of the number of type select data units, and particular functions corresponding to the number of control data units are variable based on the particular instruction type.

A 3D NAND memory device is provided in which control is performed by two microcontroller units (MCU). During manufacture of the memory device, bug fixes required for the controller may be addressed using a software solution by which an instruction requiring correction in one of the two MCUs is replaced with a corrected instruction stored in a RAM.

The present disclosure includes apparatuses and methods related to microcode instructions. One example apparatus comprises a memory storing a set of microcode instructions. Each microcode instruction of the set can comprise a first field comprising a number of control data units, and a second field comprising a number of type select data units. Each microcode instruction of the set can have a particular instruction type defined by a value of the number of type select data units, and particular functions corresponding to the number of control data units are variable based on the particular instruction type.

A memory device in accordance with a described method of operation includes a read only memory (ROM) address controller and a suspend signal generator. The ROM address controller is configured to sequentially output a plurality of operation ROM addresses at which ROM codes to be executed in response to an operation command are stored, and to suspend output of the plurality of operation ROM addresses in response to a suspend signal. The suspend signal generator is configured to generate the suspend signal that is activated during a preset period depending on whether a suspend ROM address is identical to an operation ROM address, among the plurality of operation ROM addresses, currently being output. The suspend ROM address is an address at which a ROM code, execution of which is to be suspended, among the ROM codes, is stored.

The present disclosure includes apparatuses and methods related to microcode instructions. One example apparatus comprises a memory storing a set of microcode instructions. Each microcode instruction of the set can comprise a first field comprising a number of control data units, and a second field comprising a number of type select data units. Each microcode instruction of the set can have a particular instruction type defined by a value of the number of type select data units, and particular functions corresponding to the number of control data units are variable based on the particular instruction type.

The present disclosure includes apparatuses and methods related to microcode instructions. One example apparatus comprises a memory storing a set of microcode instructions. Each microcode instruction of the set can comprise a first field comprising a number of control data units, and a second field comprising a number of type select data units. Each microcode instruction of the set can have a particular instruction type defined by a value of the number of type select data units, and particular functions corresponding to the number of control data units are variable based on the particular instruction type.