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PIC Instruction Listings
The PIC instruction set refers to the set of instructions that Microchip Technology PIC or dsPIC microcontroller supports. The instructions are usually programmed into the Flash memory of the processor, and automatically executed by the microcontroller on startup. PICmicro chips have a Harvard architecture and instruction words have unusual sizes. Originally, 12-bit instructions included 5 address bits to specify the memory operand, and 9-bit branch destinations. Later revisions added opcode bits, allowing additional address bits. In the instruction set tables that follow, register numbers are referred to as "f", while constants are referred to as "k". Bit numbers (0–7) are selected by "b". The "d" bit selects the destination: 0 indicates W, while 1 indicates that the result is written back to source register f. The C and Z status flags may be set based on the result; otherwise they are unmodified. Add and subtract (but not rotate) instructions that set C also set the DC (d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PIC Microcontroller
PIC (usually pronounced as ''"pick"'') is a family of microcontrollers made by Microchip Technology, derived from the PIC1650"PICmicro Family Tree", PIC16F Seminar Presentation originally developed by General Instrument's Microelectronics Division. The name PIC initially referred to ''Peripheral Interface Controller'',"MOS DATA 1976", General Instrument 1976 Databook and is currently expanded as ''Programmable Intelligent Computer''."1977 Data Catalog", Micro Electronics from General Instrument Corporation The first parts of the family were available in 1976; by 2013 the company had shipped more than twelve billion individual parts, used in a wide variety of embedded systems. The PIC was originally intended to be used with the General Instrument CP1600, the first commercially available single-chip 16-bit microprocessor. The CP1600 had a complex bus that made it difficult to interface with, and the PIC was introduced as a companion device offering ROM for program storage, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pointer (computer Programming)
In computer science, a pointer is an object in many programming languages that stores a memory address. This can be that of another value located in computer memory, or in some cases, that of memory-mapped computer hardware. A pointer ''references'' a location in memory, and obtaining the value stored at that location is known as ''dereferencing'' the pointer. As an analogy, a page number in a book's index could be considered a pointer to the corresponding page; dereferencing such a pointer would be done by flipping to the page with the given page number and reading the text found on that page. The actual format and content of a pointer variable is dependent on the underlying computer architecture. Using pointers significantly improves performance for repetitive operations, like traversing iterable data structures (e.g. strings, lookup tables, control tables and tree structures). In particular, it is often much cheaper in time and space to copy and dereference pointers th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Signal Processing
Digital signal processing (DSP) is the use of digital processing, such as by computers or more specialized digital signal processors, to perform a wide variety of signal processing operations. The digital signals processed in this manner are a sequence of numbers that represent samples of a continuous variable in a domain such as time, space, or frequency. In digital electronics, a digital signal is represented as a pulse train, which is typically generated by the switching of a transistor. Digital signal processing and analog signal processing are subfields of signal processing. DSP applications include audio and speech processing, sonar, radar and other sensor array processing, spectral density estimation, statistical signal processing, digital image processing, data compression, video coding, audio coding, image compression, signal processing for telecommunications, control systems, biomedical engineering, and seismology, among others. DSP can involve linear or nonli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GitHub
GitHub, Inc. () is an Internet hosting service for software development and version control using Git. It provides the distributed version control of Git plus access control, bug tracking, software feature requests, task management, continuous integration, and wikis for every project. Headquartered in California, it has been a subsidiary of Microsoft since 2018. It is commonly used to host open source software development projects. As of June 2022, GitHub reported having over 83 million developers and more than 200 million repositories, including at least 28 million public repositories. It is the largest source code host . History GitHub.com Development of the GitHub.com platform began on October 19, 2007. The site was launched in April 2008 by Tom Preston-Werner, Chris Wanstrath, P. J. Hyett and Scott Chacon after it had been made available for a few months prior as a beta release. GitHub has an annual keynote called GitHub Universe. Organizational ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temporal Multithreading
Temporal multithreading is one of the two main forms of multithreading that can be implemented on computer processor hardware, the other being simultaneous multithreading. The distinguishing difference between the two forms is the maximum number of concurrent threads that can execute in any given pipeline stage in a given cycle. In temporal multithreading the number is one, while in simultaneous multithreading the number is greater than one. Some authors use the term super-threading synonymously. Variations There are many possible variations of temporal multithreading, but most can be classified into two sub-forms: ;Coarse-grained: The main processor pipeline contains only one thread at a time. The processor must effectively perform a rapid context switch before executing a different thread. This fast context switch is sometimes referred to as a ''thread switch''. There may or may not be additional penalty cycles when switching. :There are many possible variations of coa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overflow Flag
In computer processors, the overflow flag (sometimes called the V flag) is usually a single bit in a system status register used to indicate when an arithmetic overflow has occurred in an operation, indicating that the signed Two's complement, two's-complement result would not fit in the number of bits used for the result. Some architectures may be configured to automatically generate an exception on an operation resulting in overflow. An example, suppose we add 127 and 127 using 8-bit registers. 127+127 is 254, but using 8-bit arithmetic the result would be 1111 1110 binary, which is the two's complement encoding of −2, a negative number. A negative sum of positive operands (or vice versa) is an overflow. The overflow flag would then be set so the program can be aware of the problem and mitigate this or signal an error. The overflow flag is thus set when the most significant bit (here considered the sign bit) is changed by adding two numbers with the same sign (or subtracting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carry Flag
In computer processors the carry flag (usually indicated as the C flag) is a single bit in a system status register/flag register used to indicate when an arithmetic carry or borrow has been generated out of the most significant arithmetic logic unit (ALU) bit position. The carry flag enables numbers larger than a single ALU width to be added/subtracted by carrying (adding) a binary digit from a partial addition/subtraction to the least significant bit position of a more significant word. This is typically programmed by the user of the processor on the assembly or machine code level, but can also happen internally in certain processors, via digital logic or microcode, where some processors have wider registers and arithmetic instructions than (combinatorial, or "physical") ALU. It is also used to extend bit shifts and rotates in a similar manner on many processors (sometimes done via a dedicated flag). For subtractive operations, two (opposite) conventions are employed as most ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Padauk Technology
''Pterocarpus'' is a pantropical genus of trees in the family Fabaceae. It belongs to the subfamily Faboideae, and was recently assigned to the informal monophyletic ''Pterocarpus'' clade within the Dalbergieae. Most species of ''Pterocarpus'' yield valuable timber traded as padauk (or padouk); other common names are mukwa or narra. '' P. santalinus'' also yields the most precious red sandalwood in China known as Zitan. The wood from the narra tree ('' P. indicus'') and the Burmese padauk tree ('' P. macrocarpus'') is marketed as amboyna when it has grown in the burl form. The scientific name is Latinized Ancient Greek and means "wing fruit", referring to the unusual shape of the seed pods in this genus. Uses Padauk wood is obtained from several species of ''Pterocarpus''. All padauks are of African or Asian origin. Padauks are valued for their toughness, stability in use, and decorativeness, most having a reddish wood. Most Pterocarpus' woods contain either water- or alcoh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holtek
Holtek Semiconductor () is a Taiwan-based semiconductor design centre and provider with its headquarters and design operations based in the Hsinchu Science Park in Taiwan, and has sales offices located in USA and India. Holtek's design focus is in both 32-bit and 8-bit along with Touch microcontroller development, and as of 2022 the firm employed 631 employees. Holtek also designs and provides peripheral semiconductor products such as remote control, telecommunication, power management, computer peripheral, and memory devices. Holtek's device application area is concentrated in the consumer product field such as household appliances, computer peripheral products, remote controllers, leisure products, medical equipment as well as industrial controllers. Holtek microcontrollers are in home appliances including brands such as Philips, Siemens, Märklin and Japanese brands such as Futaba and Sony. History Holtek Semiconductor was established as a design house in Taipei in 1983. From ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Addressing Mode
Addressing modes are an aspect of the instruction set architecture in most central processing unit (CPU) designs. The various addressing modes that are defined in a given instruction set architecture define how the machine language instructions in that architecture identify the operand(s) of each instruction. An addressing mode specifies how to calculate the effective memory address of an operand by using information held in registers and/or constants contained within a machine instruction or elsewhere. In computer programming, addressing modes are primarily of interest to those who write in assembly languages and to compiler writers. For a related concept see orthogonal instruction set which deals with the ability of any instruction to use any addressing mode. Caveats Note that there is no generally accepted way of naming the various addressing modes. In particular, different authors and computer manufacturers may give different names to the same addressing mode, or the same na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C Programming Language
''The C Programming Language'' (sometimes termed ''K&R'', after its authors' initials) is a computer programming book written by Brian Kernighan and Dennis Ritchie, the latter of whom originally designed and implemented the language, as well as co-designed the Unix operating system with which development of the language was closely intertwined. The book was central to the development and popularization of the C programming language and is still widely read and used today. Because the book was co-authored by the original language designer, and because the first edition of the book served for many years as the ''de facto'' standard for the language, the book was regarded by many to be the authoritative reference on C. History C was created by Dennis Ritchie at Bell Labs in the early 1970s as an augmented version of Ken Thompson's B. Another Bell Labs employee, Brian Kernighan, had written the first C tutorial, and he persuaded Ritchie to coauthor a book on the language. Ker ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel BCD Opcode
The Intel BCD opcodes are a set of six x86 instructions that operate with binary-coded decimal numbers. The radix used for the representation of numbers in the x86 processors is 2. This is called a binary numeral system. However, the x86 processors do have limited support for the decimal numeral system. In addition, the x87 part supports a unique 18-digit (ten-byte) BCD format that can be loaded into and stored from the floating point registers, from where ordinary FP computations can be performed. The integer BCD instructions are no longer supported in long mode. Usage Number representation BCD numbers can be represented in two ways in integer registers: packed decimal and unpacked decimal. * Packed (4 bits) ** In packed decimal representation a decimal digit is stored in one nibble. ** The values 10 to 15 are not used. * Unpacked (8 bits) ** In unpacked decimal representation a decimal digit is stored in one byte. ** The values 10 to 255 are not used. ** The upper nibble ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
