Watchdog timerA watchdog timer (or simply a watchdog), sometimes called a computer operating properly timer (COP timer), is an electronic or software timer that is used to detect and recover from computer malfunctions. Watchdog timers are widely used in computers to facilitate automatic correction of temporary hardware faults, and to prevent errant or malevolent software from disrupting system operation. During normal operation, the computer regularly restarts the watchdog timer to prevent it from elapsing, or "timing out".
Intel 4040The Intel 4040 microprocessor was the successor to the Intel 4004. It was introduced in 1974. The 4040 employed a 10 μm silicon gate enhancement load PMOS technology, was made up of 3,000 transistors and could execute approximately 62,000 instructions per second. General performance, bus layout and instruction set was identical to the 4004, with the main improvements being in the addition of extra lines and instructions to recognise and service interrupts and hardware Halt/Stop commands (the latter allowing operator-controlled single-stepping for debugging purposes), an extended internal stack and general-purpose "Index" register space to handle nesting of several subroutines and/or interrupts, plus a doubling of program ROM address range.
General-purpose input/outputA general-purpose input/output (GPIO) is an uncommitted digital signal pin on an integrated circuit or electronic circuit (e.g. MCUs/MPUs) board which may be used as an input or output, or both, and is controllable by software. GPIOs have no predefined purpose and are unused by default. If used, the purpose and behavior of a GPIO is defined and implemented by the designer of higher assembly-level circuitry: the circuit board designer in the case of integrated circuit GPIOs, or system integrator in the case of board-level GPIOs.
CAN busA Controller Area Network (CAN bus) is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other's applications without a host computer. It is a message-based protocol, designed originally for multiplex electrical wiring within automobiles to save on copper, but it can also be used in many other contexts. For each device, the data in a frame is transmitted serially but in such a way that if more than one device transmits at the same time, the highest priority device can continue while the others back off.
Renesas Electronicsis a Japanese semiconductor manufacturer headquartered in Tokyo, Japan, initially incorporated in 2002 as Renesas Technology, the consolidated entity of the semiconductor units of Hitachi and Mitsubishi excluding their dynamic random-access memory (DRAM) businesses, to which NEC Electronics merged in 2010, resulting in a minor change in the corporate name and logo to as it is now. In the 2000s to early 2010s, Renesas had been one of the six largest semiconductor companies in the world.
4-bit computing4-bit computing is the use of computer architectures in which integers and other data units are 4 bits wide. 4-bit central processing unit (CPU) and arithmetic logic unit (ALU) architectures are those that are based on registers or data buses of that size. Memory addresses (and thus address buses) for 4-bit CPUs are generally much larger than 4-bit (since only 16 memory locations would be very restrictive), such as 12-bit or more, while they could in theory be 8-bit. A group of four bits is also called a nibble and has 24 = 16 possible values.
TimerA timer is a specialized type of clock used for measuring specific time intervals. Timers can be categorized into two main types. The word "timer" is usually reserved for devices that count down from a specified time interval called a countdown timer, while devices that do the opposite, measuring elapsed time by counting upwards from zero, are called stopwatches. A simple example of the first type is an hourglass. Working method timers have two main groups: hardware and software timers.
Instruction set simulatorAn instruction set simulator (ISS) is a simulation model, usually coded in a high-level programming language, which mimics the behavior of a mainframe or microprocessor by "reading" instructions and maintaining internal variables which represent the processor's registers. Instruction simulation is a methodology employed for one of several possible reasons: To simulate the instruction set architecture (ISA) of a future processor to allow software development and test to proceed without waiting for the development and production of the hardware to finish.
