Microchip Technology Inc.

Brian E Boles

Rodney J Drake

Igor Wojewoda

Joseph W Triece

Bryan Kris

Randy L Yach

Stephen Bowling

James B Nolan

Joseph Alan Thomsen

Willem Smit

Henry M Pena

Sumit K Mitra

Russell E Cooper

Scott Ellison

Steven Dawson

Joshua M Conner

Timothy J Phoenix

Darrel Johansen

Steve Bradley

Gaurang Kavaiya

Steven Marsh

Richard Fischer

Maria Smit, Legal Representative

Gordon E Luke

Hassan Harb

A method of performing a direct memory access has the steps of selecting a peripheral device for performing a direct memory access through a direct memory access controller; providing a partial address by the peripheral device to the direct memory access controller; and forming the source or destination address by combining the partial address with selected bits from a source register within the direct memory access controller.

Peripheral supplied addressing in a simple DMA module

Peripheral functions of an integrated circuit device may be pooled and dynamically mapped to available external input-output connections of the integrated circuit device by using a set of configuration registers. To provide system robustness, the configuration registers may implement various levels of write protection, error correction and monitoring circuitry. One or more peripheral output functions may be mapped to one or more external output connections. Not more than one output function may be active at the same time on the same output connection. Outputs and inputs may be mapped to the same external input-output connection with or without the output being controllable for placement into an inactive state, e.g., high impedance or open collector. When the input is required to receive external data over the external input-output connection, the output may be placed into the inactive state.

Dynamic peripheral function remapping to external input-output connections of an integrated circuit device

A processor processes a variable cycle interrupt disable instruction DISI X is provided. The instruction disables interrupt processing for a variable number of processor cycles corresponding to the value specified by the instruction operand X. The DISI X instruction may be strategically used by programmers to prevent interrupts from being taken during certain intervals within a program.

Variable cycle interrupt disabling

The present invention relates generally to functional pathway configurations at the interfaces between integrated circuits (ICs) and the circuit assemblies with which the ICs communicate. More particularly, the present invention relates generally to the functional pathway configuration at the interface between one or more semiconductor integrated circuit dice, including an IC package and the circuitry of a system wherein the integrated circuit dice is a digital signal controller. Even more particularly, the present invention relates to a 18, 28, 40, 44, 64 or 80 pin functional pathway configuration for the interface between the digital signal controller and the system in which it is embedded.

Functional pathway configuration at a system/IC interface

A device including a microcontroller fabricated on a semiconductor chip is used to control an LCD display of an external system intended to be controlled by the microcontroller. The microcontroller enters a sleep state in which it operates in a battery power conservation mode during periods of time when functional activity of the microcontroller is reduced. The microcontroller awakens from the sleep state for resumption of activity when such a period ends. Timing to the LCD is decoupled from the microcontroller's own internal clock when the independent internal on-chip clock, which may be an RC oscillator, is selected by the user of the device. This allows the chip to continue to drive the LCD display even though the microcontroller's internal clock has stopped during the sleep.

Microcontroller with internal clock for liquid crystal display

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.

Data pointer for outputting indirect addressing mode addresses within a

The invention allows the programmer to designate one or more pins on a semiconductor device as either address pins, which are in addition to a predetermined set of address lines or as alternate I/O pins. The object of the invention is to provide the programmer with the capability of defining with preciseness the particular size of the address bus needed for a specific application. The invention is comprised of a programming port, optional programming logic, configuration logic, selection logic and a set of pins that may be configured as per the programmer's requirements. The invention is to exist on a single, monolithic semiconductor device.

Programmable pin designation for semiconductor devices

An improved reprogrammable memory device permits definition of a page within an array of memory cells which is variable in size, erasure of only that data contained within the defined variable page while uneffecting the remaining data in the array of memory cells and reprogramming the defined variable page. The improved reprogrammable memory device with variable page size comprises an array of memory cells where the memory cells are arranged in rows and columns; address decode logic coupled to the array of memory cells for accessing the array of memory cells; amplifier logic coupled to the array of memory cells for amplifying the voltage levels between a plurality of the memory cells and data bus when accessing the array of memory cells; column select logic coupled to the array of memory cells for determining which word from a selected row of the array of the memory cells is accessed and for connecting the plurality of memory cells to the amplifier logic; control signals coupled to the amplifier logic for accessing the array of memory cells; and, block enable signals coupled to the address decode logic for varying page size within the array of memory cells to be erased.

Reprogrammable memory device with variable page size

Apparatus for providing multiple of discrete voltage levels to drive a liquid crystal display (LCD) from an LCD module on board a microcontroller chip includes a charge pump with a switched-capacitor that develops the discrete voltages as multiples of the value of a base voltage that remains substantially without change irrespective of change in the supply voltage. A switched-capacitor charging circuit selectively charges a capacitor to produce successive additive charges individually retrievable from the capacitor. An LCD drive selectively transmits the discrete voltage levels to activate the LCD according to status of an external system under the control of the microcontroller. Voltage losses that may occur during the switched-capacitor charging are compensated to maintain the levels of the discrete voltages free of decay. Compensation is achieved by overcharging the capacitor by an amount substantially equivalent to the amount of voltage loss on the capacitor, using active feedback obtained from monitoring the charge on the capacitor.

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Mesa, AZ, United States of America

Brian E Boles