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 CPU has an upper compatibility with a low-order CPU to expand a continuously usable address space relatively. For latching data information, registers are constructed for being an address register with a bit number larger than the address bit number of a low-order CPU. The data information has its byte/word size specified by the size bit of an operation code. The utilization of the data information of a long word size is specified by either the prefix code or the operation code to which is newly added the same bit number as that of the low-order CPU. For the data information of the byte size, the high-/low-orders of the byte size register to be utilized are specified by predetermined 1 bit of a register specifying field. For the data information of the word size, the high-/low-orders of the word size register are specified by the predetermined 1 bit of that data information.

Abstract: A circuit by which an SWI instruction held in a memory circuit is switchedly input in response to a signal supplied externally is provided in a processor, whereby the substitution of a program word can be realized using such an internal circuit, so that a high-speed and reliable break in program execution can be effected. Moreover, an interrupt function separate from normal interrupts is established by setting a specified operation mode, whereby, when a data processor is used as an emulator, the break of a user program including the ordinary interrupt processes can be easily effected by utilizing the special interrupt function. Also, by additionally providing the function of delivering out a signal indicative of the break status, an external circuit can be simplified.

Abstract: An electrically rewritable flash memory device which has a memory cell array arranged in rows and columns of memory cells and which is divided into a plurality of memory blocks having different memory capacities. Each memory block having one or more rows of memory cells. A common voltage control circuit is provided for each of the memory blocks for applying a first potential to a common conductor for a memory block containing a memory cell selected with a selection voltage applied to its associated data line conductor for a writing operation and a second potential higher than the first potential to a common conductor for a memory block containing a memory cell unselected with the selection voltage applied to its associated data line conductor and containing no selected memory cell for a writing operation.

Abstract: In developing the function of a data processing system using a semiconductor integrated circuit for data processing, comprising a non-volatile logical function block to which data is written electrically and a logical operation block utilizing the logical function block to execute the logic operation, data corresponding to the required specification and function of the system is written in the logical function block. Thereby, flexibility is obtained for setting and changing the required function to the semiconductor integrated circuit. The semiconductor integrated circuit also has an operation specification written to the logical block by a writing device designed to write to a non-volatile semiconductor storage device thereby improving the convenience of setting the functions required of the semiconductor integrated circuit.

Abstract: A circuit by which an SWI instruction held in a memory circuit is switchedly input in response to a signal supplied externally is provided in a processor, whereby the substitution of a program word can be realized using such an internal circuit, so that a high-speed and reliable break in program execution can be effected. Moreover, an interrupt function separate from normal interrupts is established by setting a specified operation mode, whereby, when a data processor is used as an emulator, the break of a user program including the ordinary interrupt processes can be easily effected by utilizing the special interrupt function. Also, by additionally providing the function of delivering out a signal indicative of the break status, an external circuit can be simplified.

Abstract: A logic circuit built in a single-chip microprocessor is configured of electrically-programmable memory elements, and information is written into the memory elements from outside, whereby the logic circuit having any desired logical functions can be constructed. The writing operation of the memory elements can be executed in a short time, and a user can obtain the single-chip microprocessor having hardware of peculiar prescribed specifications, in a short period.

Abstract: A reception unit for providing data supplied from a serial input circuit to an inner bus and a transmission unit for providing the data supplied from the inner bus to a serial output circuit hold at least two sorts of control procedures among HDLC procedure, BI-SYNC procedure and start-stop synchronous procedure as control procedures for data transmission/reception, and the control procedures held by these units can be selected alternatively based on a command of the processor.

Abstract: A logic circuit built in a single-chip microprocessor is configured of electrically-programmable memory elements, and information is written into the memory elements from outside, whereby the logic circuit having any desired logical functions can be constructed. The writing operation of the memory elements can be executed in a short time, and a user can obtain the single-chip microprocessor having hardware of peculiar prescribed specifications, in a short period.

Abstract: A single chip microprocessor 1 includes a CPU 2 and a sub-processor 5 for software implementation of peripheral functions of the microprocessor 1. Sub-processor 5 includes electrically writable internal storage devices microprogram memory unit 13 and sequence control memory unit 62 for storing the software. Peripheral functions are defined and/or modified by writing software into the memory units 13 and 62. Accordingly, the time it takes to define and/or modify the peripheral functions is the time it takes to program the memory units 13 and 62. The sub-processor 5 also includes an execution unit 16 for executing a plurality of tasks and an address control circuit 14 for providing addresses to the microprogram memory unit 13. Additionally, the microprogram memory unit 13 provides microinstructions to the execution unit 16. The sequence control memory unit 62 is part of the address control circuit 14 which also includes a plurality of address registers MAR0 to MAR11.

Abstract: A single chip microcomputer formed on a semiconductor substrate includes a central processing unit, a ROM storing therein a program for operating the central processing unit, a digital signal processor, and a multi-port RAM. The digital signal processor develops an outline font on the multi-port RAM in accordance with a program stored in a storage unit provided in the digital signal processor. This eliminates the necessity of development of an outline font by the central processing unit and allows high speed execution of such development of an outline font. Further, the central processing unit and the digital signal processor can operate in a parallel relationship.

Abstract: A reception unit for providing data supplied from a serial input circuit to an inner bus and a transmission unit for providing the data supplied from the inner bus to a serial output circuit hold at least two types of control procedures selected from HDLC procedure, BI-SYNC procedure and start-stop synchronous procedure as control procedures for data transmission/reception, and the control procedures held by these units can be selected alternatively based on a mode control data written in a mode control register by a processor.

Abstract: In a microprocessor, a minimum instruction code length is set to a predetermined number of bits (e.g. one byte) length. One feature of the invention is that an instruction set which can selectively expand the instruction code length at a unit of the predetermined number of bits is used. Another feature is that an operand addressing mode and a type of operation for an operand are designated by separate predetermined number of code bits which are coded in a common coding scheme so that an instruction decoder is shared by those codes.

Abstract: A wait signal formed by a program wait circuit incorporated in a microprocessor is transmitted to outside circuitry, such as a slave microprocessor or a direct memory access control device. Thereby an outside device assumes the functions of bus master which is incorporated into a wait operation for access to a memory unit. With such a construction, a microcomputer system comprising a plurality of devices to be made into a bus mask can be simplified.

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.

Abstract: A circuit by which an SWI instruction held in a memory circuit is switchedly input in response to a signal supplied externally is provided in a processor, whereby the substitution of a program word can be realized using such an internal circuit, so that a high-speed and reliable break in program excution can be effected. Moreover, an interrupt function separate from normal interrupts is established by setting a specified operation mode, whereby, when a data processor is used as an emulator, the break of a user program including the ordinary interrupt processes can be easily effected by utilizing the special interrupt function. Also, by additionally providing the function of delivering out a signal indicative of the break status, an external circuit can be simplified.

Abstract: A semiconductor circuit is constructed of a digital signal input circuit and an analog signal input circuit to be fed with an analog signal through a multiplexer. An analog signal wiring layer to be coupled to the input terminal of the analog signal input circuit is made not to intersect any digital signal wiring layer. As a result, an undesirable coupling capacitance to be formed by the intersecting wiring layers, if any, is not coupled to the analog signal wiring layer. Because of the absence of the undesirable coupling capacitance it is possible to substantially reduce the crosstalk of the digital signal from the digital signal wiring layer to the analog signal wiring layer.

Abstract: A data memory system includes a plurality of buffer regions each having a constant size so that serial data may be stored by linking the buffer regions. A descripter provided to correspond to each of the buffer regions includes memory region addressing information indicating the head address of the corresponding buffer region, data delimiting information indicating whether or not the data to be stored is terminated in the corresponding buffer region, and chain information indicating the head address of a next subsequent descripter.

Abstract: A semiconductor circuit is constructed of a digital signal input circuit and an analog signal input circuit to be fed with an analog signal through a multiplexer. An analog signal wiring layer to be coupled to the input terminal of the analog signal input circuit is made not to intersect any digital signal wiring layer. As a result, an undesirable coupling capacitance to be formed by the intersecting wiring layers, if any, is not coupled to the analog signal wiring layer. Because of the absence of the undesirable coupling capacitance it is possible to substantially reduce the crosstalk of the digital signal from the digital signal wiring layer to the analog signal wiring layer.

Abstract: The data processing system has a data processing function to perform a data processing by specifying one of a plurality of register groups according to an instruction. The instruction contains information for indicating a change from one register group to another register group and information for specifying a desired one or two or more registers in said register group. This makes it possible to transfer the contents of the desired one or two or more registers to other registers at the time of a register change.