Abstract: A semiconductor device having and electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.

Abstract: A microcomputer MCU adopting the general purpose register method is enabled to have a small program capacity or a high program memory using efficiency and a low system cost, while enjoying the advantage of simplification of the instruction decoding as in the RISC machine having a fixed length instruction format of the prior art, by adopting a fixed length instruction format having a power of 2 but a smaller bit number than that of the maximum data word length fed for instruction execution. And, the control of the coded division is executed by noting the code bits.

Abstract: A microcomputer CMU adopting the general purpose register method is enabled to have a small program capacity or a high program memory using efficiency and a low system cost, while enjoying the advantage of simplification of the instruction decoding as in the RISC machine having a fixed length instruction format of the prior art, by adopting a fixed length instruction format having a power of 2 but a smaller bit number than that of the maximum data word length fed for instruction execution. And, the control of the coded division is executed by noting the code bits.

Abstract: A branch instruction format has different respective field lengths for conditional branch instructions and unconditional branch instructions. A conditional branch instruction has a first bit length and a first area for a displacement designating an address to be jumped, wherein the first area has a second bit length that is smaller than the first bit length. An unconditional branch instruction also has the first bit length, and a second area for a displacement designating an address to be jumped, wherein the second area has a third bit length that is different from the first and second bit lengths.

Abstract: A semiconductor device having and electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.

Abstract: A semiconductor device having and electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.

Abstract: Herein disclosed is a microcomputer MCU adopting the general purpose register method. The microcomputer is enabled to have a small program capacity or a high program memory using efficiency and a low system cost, while enjoying the advantage of simplification of the instruction decoding as in the RISC machine having a fixed length instruction format of the prior art, by adopting a fixed length instruction format having a power of 2 but a smaller bit number than that of the maximum data word length fed to instruction execution means. And, the control of the coded division is executed by noting the code bits.

Abstract: A semiconductor integrated circuit device having a processing unit and a memory which stores data to be processed by the processing unit and which provides data to the processing unit through the data bus in response to accessing instructions from the processing unit through the address bus. The memory has a plurality of memory blocks each of which has a plurality of electrically programmable nonvolatile memory cells arranged in rows and columns in which each nonvolatile memory cell is coupled to one of a plurality of word lines and one of a plurality of data lines of the memory. The memory blocks formed can be facilitated with different memory capacities, including through controlling the number of rows or columns of memory cells associated therewith.

Abstract: A microcomputer MCU adopting the general purpose register method is enabled to have a small program capacity or a high program memory using efficiency and a low system cost, while enjoying the advantage of simplification of the instruction decoding as in the RISC machine having a fixed length instruction format of the prior art, by adopting a fixed length instruction format having a power of 2 but a smaller bit number than that of the maximum data word length fed for instruction execution. And, the control of the coded division is executed by noting the code bits.

Abstract: A semiconductor device having and electrically erasable and programmable nonvolatile memory, for example, a rewritable nonvolatile memory including memory cells arranged in rows and columns and disposed to facilitate both flash erasure as well as selective erasure of individual units of plural memory cells. The semiconductor device which functions as a microcomputer chip also has a processing unit and includes an input terminal for receiving an operation mode signal for switching the microcomputer between a first operation mode in which the flash memory is rewritten under control of a processing unit and a second operation mode in which the flash memory is rewritten under control of separate writing circuit externally connectable to the microcomputer.

Abstract: A single chip semiconductor integrated circuit device having a central processing unit (CPU) and a flash memory which stores data to be processed by the CPU and which provides data to the CPU through the data bus in response to accessing instructions from the CPU through the address bus. The flash memory is constituted by a plurality of memory blocks each of which has a plurality of electrically programmable nonvolatile memory cells arranged in rows and columns in which each nonvolatile memory cell is coupled to one of a plurality of word lines and one of a plurality of data lines of the flash memory. The memory blocks formed can be facilitated with different memory capacities, including through controlling the number of rows or columns of memory cells associated therewith.

Abstract: Herein disclosed is a microcomputer MCU adopting the general purpose register method. The microcomputer is enabled to have a small program capacity or a high program memory using efficiency and a low system cost, while enjoying the advantage of simplification of the instruction decoding as in the RISC machine having a fixed length instruction format of the prior art, by adopting a fixed length instruction format having a power of 2 but a smaller bit number than that of the maximum data word length fed to instruction execution means. And, the control of the coded division is executed by noting the code bits.

Abstract: A division method and circuit performs a division for signed data by adding or subtracting a divisor to or from the dividend or the partial remainder from the division, according to the sign of the divisor or the dividend and the partial remainder to acquire a new partial remainder. The division is repeated a predetermined number of times in which a quotient bit is acquired according to the sign of the acquired partial remainder or the divisor. The dividend is corrected by subtracting 1, which is the significance of an LSB of the corresponding dividend, from the dividend when the sign of the dividend is negative, and the corrected dividend is used for the division processing.

Abstract: In microcomputers and digital signal processors in which a central processing unit for controlling the entire system and a digital signal processing unit having a product sum function required to process digital signals efficiently are mounted on one and the same chippthis invention prevents an increase in the number of processing steps caused by differing types of data handled by the calculators, thereby enhancing the efficiency of the digital signal processing.The digital signal processing unit is made a calculation unit that handles fixed-point data, and an instruction calling for execution of a fixed-point data calculation is provided separately from the conventional integer calculation instruction.

Abstract: A built-in memory is divided into the following two types: first memories 5 and 7 and second memories 4 and 6, and made accessible in parallel by third buses XAB and XDB and second buses YAB and YDB respectively. Thereby, a CPU core 2 can simultaneously transfer two data values from the built-in memory to a DSP engine 3. Moreover, the third buses XAB and XDB and the second buses YAB and YDB are also separate from first buses IAB and IDB to be externally interfaced and the CPU core 2 can access an external memory in parallel with the access to the second memories 4 and 6 and the first memories 5 and 7.

Abstract: A semiconductor integrated circuit device formed on a single chip or a microcomputer integrated on a semiconductor chip includes a central processing unit (CPU), an interface circuit (or an input/output port), a bus coupled to the CPU and the interface circuit (or the input/output port) and a variable logic circuit (or a subprocessor). The variable logic circuit (or the subprocessor) includes non-volatile memory elements storing instructions, a control circuit generating control signals in accordance with the stored instructions, and an arithmetic logic unit controlled by the generated control signals. Information can be written into the non-volatile memory elements from outside to construct the variable logic circuit or the subprocessor with any desired logical functions.

Abstract: Expansion registers E0 to E7 are added to the existing general registers R0 to R7 built on-chip in a CPU 1 of 8 bits so that all the registers including the added expansion registers may be grasped in its entirety as address data to access to a memory or the like. The address operation is executed at a unit including both the expansion register and the corresponding general register. All the registers including the expansion registers are grasped as one unit of address data to handle the carry or borrow caused in the address operation. Since the expansion registers have their applications limited to the generation of address, the number of kinds or combinations of executable instructions is reduced without inviting a serious reduction in the data processing ability thereby to suppress the increase in the logical and physical scales of the CPU.The register is given 32 bits in its entirety by adding the expansion register Ei of 16 bits to the general registers RiH and RiL of 16 bits of the 8-bit CPU.

Abstract: A single chip semiconductor integrated circuit device having a central processing unit (CPU) and a flash memory which stores data to be processed by the CPU and which provides data to the CPU through the data bus in response to accessing instructions from the CPU through the address bus. The flash memory is constituted by a plurality of memory arrays in which a plurality of word lines are commonly employed for all of the memory arrays and a plurality of data lines are distributed amongst the memory arrays. The nonvolatile memory cells are arranged in a manner in which plural memory blocks are formed. The memory blocks formed can be facilitated with different memory capacities. This is achieved by having one or more rows of memory cells associated with one or more word lines provided within a memory block.

Abstract: Expansion registers E0 to E7 are added to the existing general registers R0 to R7 built on-chip in an 8-bit CPU (1) so that all the registers including the added expansion registers may be grasped in its entirety as address data to access to a memory or the like. The address operation is executed at a unit including both the expansion register and the corresponding general register. All the registers including the expansion registers are grasped as one unit of address data to handle the carry or borrow caused in the address operation. Since the expansion registers have their applications limited to the generation of address, the number of kinds or combinations of executable instructions is reduced without inviting a serious reduction in the data processing ability thereby to suppress the increase in the logical and physical scales of the CPU. The register is given 32 bits in its entirety by adding the expansion register Ei of 16 bits to the general registers RiH and RiL of 16 bits of the 8-bit CPU.

Abstract: A microprocessor has a register in which attributive data corresponding to a memory to be coupled to the microprocessor is written, and a control circuit which controls address signals to be supplied to the memory in accordance with the attributive data. The attributive data is composed of range data for discriminating ranges of address data supplied to an address bus, system data indicative of addressing systems of the memories corresponding to the respective address ranges, and bit number data indicative of numbers of address bits of the memories. Thus, in a case where the memory to be accessed is of an address multiplexing system as in a dynamic RAM, the address data of the address bus is divided into row address data and column address data, which are then supplied to the memory in time division.