A virtualized window will appear on-screen, where PlayKey initializes the launcher and the game begins to run in fullscreen.
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A user initializes these qubits, which is sort of like setting the weights on a weighted die, and then lets them interact via the mathematical rules of quantum mechanics.
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To run the system, you first impose a horizontal magnetic field, which initializes the qubits to an equal superposition of up and down—the equivalent of a blank slate.
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And like the standard Canary, the Flex also has built-in night vision detect that will trigger when the camera senses low light — or when the user initializes it manually over the app.
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ICKDSF ("Device Support Facility") installs, initializes and maintains DASD, either under an operating system, or standalone.
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The server performs a syntax check and initializes server internal resources for later use. The MySQL server supports using anonymous, positional placeholder with ?. See example in.
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IO.SYS initializes the minimal File Allocation Table driver and loads MSDOS.SYS into memory. It then displays "Starting Windows" depending on the BootDelay line in the MSDOS.SYS file.
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Synthesis is the step where the structure of the flowsheet is chosen. It is also in this step that one initializes values for variables which one is free to set.
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The first line, x=1, creates a global variable `x` and initializes it to `1`. The second line, function g() { echo $x ; x=2 ; }, defines a function `g` that prints out ("echoes") the current value of `x`, and then sets `x` to `2` (overwriting the previous value). The third line, function f() { local x=3 ; g ; } defines a function `f` that creates a local variable `x` (hiding the identically named global variable) and initializes it to `3`, and then calls `g`. The fourth line, f, calls `f`.
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The interface of that original system serves as a de facto standard. The BIOS in modern PCs initializes and tests the system hardware components, and loads a boot loader from a mass memory device which then initializes an operating system. In the era of DOS, the BIOS provided BIOS interrupt calls for the keyboard, display, and other input/output (I/O) devices that standardized an interface to application programs and the operating system. More recent operating systems do not use the BIOS interrupt calls after loading.
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Diagram showing how open system (hydraulic) pingos are formed. Hydraulic (open-system) pingos result from groundwater flowing from an outside source, i.e. sub-permafrost or intra-permafrost aquifers. Hydrostatic pressure initializes the formation of the ice core as water is pushed up and subsequently freezes.
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The translator derives a `.po` (Portable Object) file from the template using the `msginit` program, then fills out the translations. `msginit` initializes the translations so, for instance, for a French language translation, the command to run would be: msginit --locale=fr --input=name.pot This will create `fr.po`.
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A hardware reset or hard reset of a computer system is a hardware operation that re-initializes the core hardware components of the system, thus ending all current software operations in the system. This is typically, but not always, followed by booting of the system into firmware that re-initializes the rest of the system, and restarts the operating system. Hardware resets are an essential part of the power-on process, but may also be triggered without power cycling the system by direct user intervention via a physical reset button, watchdog timers, or by software intervention that, as its last action, activates the hardware reset line (e.g, in a fatal error where the computer crashes).
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Redox reactions take place in the cell between the metals and oxygen containing species in the cell to produce ROS. Other novel techniques include utilizing quantum dots such as cadmium telluride, under a bright light source to excite and release electrons; this process initializes ROS production similar to the metal nanoparticles.
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Memory allocated with the must be deallocated with the operator, rather than . Using the inappropriate form results in undefined behavior. C++ compilers are not required to generate a diagnostic message for using the wrong form. The C++11 standard specifies an additional syntax, p = new T[N] {initializer1, ..., initializerN}; that initializes each to .
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The zero or ultra-thin client initializes the network to gather required configuration files that then tell it where its OS binaries are stored. The entire zero client device runs via the network. This creates a single point of failure, in that, if the network goes down, the device is rendered useless.
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When the existing leader fails or when the algorithm initializes, a new leader needs to be elected. In this case, a new term starts in the cluster. A term is an arbitrary period of time on the server for which a new leader needs to be elected. Each term starts with a leader election.
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In the PC bootup sequence, the first sector of the boot disk is loaded into memory and executed. If this is the DOS boot sector, it loads the first three sectors of into memory and transfers control to it. then: # Loads the rest of itself into memory. # Initializes each default device driver in turn (console, disk, serial port, etc..).
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On September 18, 2018, BlueStacks announced the release of its latest flagship version, BlueStacks 4. BlueStacks 4 benchmarks 6-8x faster than every major mobile phone according to the Antutu benchmark. BlueStacks 4 also includes dynamic resource management which only initializes the required Android libraries thus freeing resources. A new dock and search offer a clean user interface.
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It also places various configuration parameters into memory, and transfers control to the kernel. The kernel reads these parameters, initializes and runs, replacing DOS/Windows completely. Optionally, it can be configured to supply the kernel with an initial RAM disk, loaded into memory before transferring control to the Linux kernel. It passes to the kernel information about the RAM disk and its location.
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XAML file containing this list along with the entry point (class and assembly). It can be hosted in any HTML file using an object tag, for example: A Silverlight project contains the `Silverlight.js` and `CreateSilverlight.js` files which initializes the Silverlight plug-in for use in HTML pages, a XAML file for the UI, and code-behind files for the application code.
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This is the first stage of the UEFI boot but may have platform specific binary code that precedes it. (e.g., Intel ME, AMD PSP). Minimal code written in assembly for the specific architecture. It initializes a temporary memory (often CPU cache as RAM) and serves as the system’s software root of trust with the option of verifying PEI before hand-off.
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The most difficult hardware that coreboot initializes is the DRAM controllers and DRAM. In some cases, technical documentation on this subject is NDA restricted or unavailable. RAM initialization is particularly difficult because before the RAM is initialized it cannot be used. Therefore, to initialize DRAM controllers and DRAM, the initialization code may have only the CPU's general purpose registers or Cache-as-RAM as temporary storage.
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An object declared, for example, as will contain two members, and , plus three constructor functions. The first (default) constructor initializes both members with the default values and , whereas the second one accepts one parameter of each type. The third is a template copy-constructor which will accept any , provided the types and are capable of implicit conversion to and respectively. GCC's implementation defines the mechanism as follows.
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When the runspace is created, the Windows PowerShell runtime initializes the instantiation, including initializing the providers and enumerating the cmdlets, and updates the `SessionState` object accordingly. The Runspace then must be opened for either synchronous processing or asynchronous processing. After that it can be used to execute commands. To execute a command, a pipeline (represented by a `Pipeline` object) must be created and associated with the runspace.
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To construct constant expression data values from user-defined types, constructors can also be declared with `constexpr`. A `constexpr` constructor's function body can contain only declarations and null statements, and cannot declare variables or define types, as with a `constexpr` function. There must exist argument values such that, after argument substitution, it initializes the class's members with constant expressions. The destructors for such types must be trivial.
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Activation executes Built-in-Test and initializes position counters for the actuators. Each bolt actuator is extended two revolutions, then retracted three to verify operability of both the bolt and the motor. Latches are driven one at a time to the open position which, for Node Radial Ports, deploys M/D Covers. All 20 actuators are set to the operational initial positions (0 revolutions for the bolts, 202° for latches).
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When the constructor is called, torch initializes and sets a Lua table with the user- defined metatable, which makes the table an object. Objects created with the torch factory can also be serialized, as long as they do not contain references to objects that cannot be serialized, such as Lua coroutines, and Lua userdata. However, userdata can be serialized if it is wrapped by a table (or metatable) that provides `read()` and `write()` methods.
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Hacking coreboot at Denver 2008 summit. Since coreboot must initialize the bare hardware, it must be ported to every chipset and motherboard that it supports. Before initializing RAM, coreboot initializes the serial port (addressing cache and registers only), so it can send out debug text to a connected terminal. It can also send byte codes to port 0x80 that are displayed on a two-hex-digit display of a connected POST card.
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GConf is currently based on the C implementation of CORBA named ORBit. Its architecture consists of a session daemon that initializes various sources of configuration schemas on user login. Each source is based on a specific backend that translates the key and value pairs that compose the configuration database; the default backend is based on XML. At this time, this is the only working backend for GConf, although an LDAP backend existed in embryonic form.
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Every mission initializes with a briefing stage, allowing the player to choose their equipment, coordinate their attacks, and develop the plot. Throughout each mission the player directly controls one team member, and can take control of any living operative. However, any casualties cannot be used in future missions unless the mission is reset. In multiplayer, the game pits two teams of players against each other in order to complete objectives depending on the game mode.
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The first transition is the start transition that initializes the local variable. A connection request message conReq is sent, a 5 seconds timer conReqTimer is started, and the state machine goes to the connecting state. In the connecting state if the timer goes off -that is equivalent to a message receive- the connection request is sent again up to 10 times. If a connection confirmation is received the state machine goes to connected state.
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COM /Y This configuration sets common environment variables, loads a disk cache, places common directories into the default PATH, and initializes the DOS mouse / keyboard drivers. The `PROMPT` command sets the prompt to "C:\>" (when the working directory is the root of the C drive) instead of simply "C>" (the default prompt, indicating only the working drive and not the directory therein). In general, device drivers were loaded in `CONFIG.SYS`, and programs were loaded in the `AUTOEXEC.
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The application declares and initializes an iterator that locates and returns qualified objects as soon as they are located. The Objectivity/DB Parallel Query Engine splits queries into subtasks directed at individual databases or containers. Remote query agents service each subtask and return results to the iterator. The Parallel Query Engine has two replaceable components: a splitter that can determine how to best subdivide the task and a filter in the query agent that can further refine a query.
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To make it easy to distribute middleware, T-Kernel has separate specification for subsystem and device driver which will be suitable for different types of middleware APIs. A real-time OS appropriate for individual application can be created by combining the middleware called T-Kernel Extension with the T-Kernel. T-Monitor initializes hardware and handles the interrupt set up at the start. T-Monitor lessens hardware-dependency of T-Kernel, and improves the application portability.
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Each palette register contain a 3×6 bit RGB value, selecting a color from the 18-bit gamut of the DAC. These color registers are initialized to default values IBM expected to be most useful for each mode. For instance, EGA 16-color modes initialize to the default CGA 16-color palette, and the 256-color mode initializes to a palette consisting of 16 CGA colors, 16 grey shades, and then 216 colors chosen by IBM to fit expected use cases.
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When the program initializes its use of the disk, it provides the kernel with a function that the kernel can use to determine which blocks the program controls. The kernel uses this callback to verify that when it allocates a new block, the program claims only the block that was allocated in addition to those it already controlled. ; Networking : The kernel implements a programmable packet filter, which executes programs in a byte code language designed for easy security-checking by the kernel.
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The half-head arrows indicate a random gap between various areas of virtual memory. At any point when the kernel initializes the process, the length of these arrows can be considered to grow longer or shorter from this template independent of each other. During the course of a program's life, the heap, also called the data segment or .bss, will grow up; the heap expands towards the highest memory address available. Conversely, the stack grows down, towards the lowest memory address, 0.
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Initially distraught with her condition, she eventually finds solace in the fact her existence is the key to finally rebooting the Matrix and erasing Oligarch override control once and for all. She ultimately meets her end in the Source of The Matrix, merging with a human inside the core of the Machine code base itself, combining the three core groups; Man, Machine and Program. This initializes the final reboot sequence, removing the Oligarch control and allowing the Machines to finally exist without fear of cruel masters.
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For most file systems, a program initializes access to a file in a file system using the open system call. This allocates resources associated to the file (the file descriptor), and returns a handle that the process will use to refer to that file. In some cases the open is performed by the first access. The same file may be opened simultaneously by several processes, and even by the same process, resulting in several file descriptors for the same file; depending on the file organization and filesystem.
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This method had a revival with the uprise of mobile devices and device targeting. URL hijacking is an off-domain redirect technique that exploited the nature of the search engine's handling for temporary redirects. If a temporary redirect is encountered, search engines have to decide whether they assign the ranking value to the URL that initializes the redirect or to the redirect target URL. The URL that initiates the redirect may be kept to show up in search results, as the redirect indicates a temporary nature.
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Models use systems of differential equations based on the laws of physics, fluid motion, and chemistry, and use a coordinate system which divides the planet into a 3D grid. Winds, heat transfer, radiation, relative humidity, and surface hydrology are calculated within each grid and evaluate interactions with neighboring points. A global forecast model is a weather forecasting model which initializes and forecasts the weather throughout the Earth's troposphere. It is a computer program that produces meteorological information for future times at given locations and altitudes.
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Many iterative square root algorithms require an initial seed value. The seed must be a non-zero positive number; it should be between 1 and S, the number whose square root is desired, because the square root must be in that range. If the seed is far away from the root, the algorithm will require more iterations. If one initializes with x0 = 1 (or S), then approximately \tfrac12 \vert \log_2 S \vert iterations will be wasted just getting the order of magnitude of the root.
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The Serial ATA spec requires SATA device hot plugging; that is, devices that meet the specification are capable of insertion or removal of a device into or from a backplane connector (combined signal and power) that has power on. After insertion, the device initializes and then operates normally. Depending upon the operating system, the host may also initialize, resulting in a hot swap. The powered host and device do not need to be in an idle state for safe insertion and removal, although unwritten data may be lost when power is removed.
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The MakeSet operation adds a new element. This element is placed into a new set containing only the new element, and the new set is added to the data structure. If the data structure is instead viewed as a partition of a set, then the MakeSet operation enlarges the set by adding the new element, and it extends the existing partition by putting the new element into a new subset containing only the new element. In a disjoint-set forest, MakeSet initializes the node's parent pointer and the node's size or rank.
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Delayed auto-start services have been added in Windows Vista, in order to solve the problem of a prolonged system startup, as well as to speed-up the start of critical services that cannot be delayed. Originally the auto-start method of service initialization was designed for essential system services upon which other applications and services depend. The SCM initializes the delayed services only after handling all the non-delayed auto-start services, by invoking the `ScInitDelayStart()` function. This function queues a delayed (120 seconds by default) work item associated with a corresponding worker thread.
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If Ctrl+Alt+Delete was pressed ("warm boot"), a special flag value stored in nonvolatile BIOS memory ("CMOS") tested by the BIOS allows bypass of the lengthy POST and memory detection. The POST identifies, and initializes system devices such as the CPU, RAM, interrupt controllers, DMA controllers, chipset, video display card, keyboard, hard disk drive, optical disc drive and other hardware. Early IBM PCs had a routine in the POST that would download a program into RAM through the keyboard port and run it. This feature was intended for factory test or diagnostic purposes.
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To understand how external variables relate to the `extern` keyword, it is necessary to know the difference between defining and declaring a variable. When a variable is defined, the compiler allocates memory for that variable and possibly also initializes its contents to some value. When a variable is declared, the compiler requires that the variable be defined elsewhere. The declaration informs the compiler that a variable by that name and type exists, but the compiler does not need to allocate memory for it since it is allocated elsewhere.
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Dojo provides a packaging system to facilitate modular development of functionality in individual packages and sub-packages; the base Dojo "bootstrap" script initializes a set of hierarchical package namespaces — "io", "event", etc. — under a root "dojo" namespace. After initialization of the root namespace, any Dojo package can be loaded (via XMLHttpRequest or other similar transport) by using utility functions supplied in the bootstrap. It is also possible to initialize additional namespaces within or parallel to the "dojo" namespace, allowing extensions of Dojo or the development of private Dojo-managed namespaces for third-party libraries and applications.
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The CORBA specification dictates there shall be an ORB through which an application would interact with other objects. This is how it is implemented in practice: # The application simply initializes the ORB, and accesses an internal Object Adapter, which maintains things like reference counting, object (and reference) instantiation policies, and object lifetime policies. # The Object Adapter is used to register instances of the generated code classes. Generated code classes are the result of compiling the user IDL code, which translates the high-level interface definition into an OS- and language-specific class base for use by the user application.
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Mac OS X booting up in single-user mode In PowerPC-based Macintoshes, the boot process starts with the activation of BootROM, the basic Macintosh ROM, which performs a Power On Self Test to test hardware essential to startup. On the passing of this test, the startup chime is played and control of the computer is passed to OpenFirmware. OpenFirmware initializes the Random Access Memory, Memory Management Unit and hardware necessary for the ROM's operation. The OpenFirmware then checks settings, stored in NVRAM, and builds a list of all devices on a device tree by gathering their stored FCode information.
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LZ78 algorithms achieve compression by replacing repeated occurrences of data with references to a dictionary that is built based on the input data stream. Each dictionary entry is of the form `dictionary[...] = {index, character}`, where index is the index to a previous dictionary entry, and character is appended to the string represented by . For example, "abc" would be stored (in reverse order) as follows: `dictionary[k] = {j, 'c'}, dictionary[j] = {i, 'b'}, dictionary[i] = {0, 'a'}`, where an index of 0 specifies the first character of a string. The algorithm initializes last matching index = 0 and next available index = 1.
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Basically, Argo builds on the existing upper-ocean thermal networks, extending their spatial and temporal coverage, depth range and accuracy, and improving them through the addition of salinity and velocity measurements. The Argo system helps to study quantitatively the evolving state of the upper ocean and the patterns of its climate variability, including heat, fresh water storage and transport. Apart from these, it also enhances the value of altimeter by sufficiently improving the coverage and resolution of sea surface height variability interpretation and initializes the ocean and coupled forecast models for data assimilation and dynamic model testing.
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A zero client makes use of very lightweight firmware that merely initializes network communication through a basic GUI (Graphical User Interface), decodes display information received from the server, and sends local input back to the host. A device with such simple functionality has less demand for complex hardware or silicon, and therefore becomes less prone to obsolescence. Another key benefit of the zero client model is that its lightweight firmware represents an ultra-small attack surface making it more secure than a thin client. Further, the local firmware is so simple that it requires very little setup or ongoing administration.
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More common is to use the loop setup instruction (represented in assembly as either with pseudo-instruction and , or in a single line as ), which optionally initializes and sets and to the desired values. This only requires 4–6 bytes, but can only set and within a limited range relative to where the loop setup instruction is located. P0 = array + 396; R0 = 100; LC0 = R0; LOOP my_loop LC0; // sets LT0 and LB0 LOOP_BEGIN my_loop; // pseudo-instruction; generates a label used to compute LT0 // LC0 cannot be written directly to memory, // so we must use a temporary register.
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It does this by making a definition for every parameter of the Simulink model. It can generate a function which initializes the loading of a newly developed control system and, it can generate the step function which holds the code for the logic of each module. ;Orchestra HMI HMI is a Java application (therefore a cross-platform one), that looks for and interacts with different parts of a control system. Orchestra HMI has a graphic interface (including a touch screen) which can run on any common PC. It can be customised to suit the user and provides user authentication.
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Curiously, although it was originally designed for acyclic graphical models, it was found that the Belief Propagation algorithm can be used in general graphs. The algorithm is then sometimes called loopy belief propagation, because graphs typically contain cycles, or loops. The initialization and scheduling of message updates must be adjusted slightly (compared with the previously described schedule for acyclic graphs) because graphs might not contain any leaves. Instead, one initializes all variable messages to 1 and uses the same message definitions above, updating all messages at every iteration (although messages coming from known leaves or tree-structured subgraphs may no longer need updating after sufficient iterations).
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The yellow- spectrum HPS lamps also slowly dim over time but are known for "cycling," where the lamp cycles on and off when it has reached the end of its life cycle. When cycling, the arc within the lamp extinguishes and the lamp must cool down before the starter circuit initializes a new arc. This has been the most recognized downfall of HPS. Some HPS lamps start to burn a pinkish/reddish color at the end of their life (usually when already cycling), or start to burn a pinkish/white color and go dim, or also burn out at the end of their life cycle whether they cycle or not.
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For example, in Java if a call to a constructor has been inlined then the shared variable may immediately be updated once the storage has been allocated but before the inlined constructor initializes the object. # Thread B notices that the shared variable has been initialized (or so it appears), and returns its value. Because thread B believes the value is already initialized, it does not acquire the lock. If B uses the object before all of the initialization done by A is seen by B (either because A has not finished initializing it or because some of the initialized values in the object have not yet percolated to the memory B uses (cache coherence)), the program will likely crash.
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Depending on what features the DMA controller provides, these control registers might specify some combination of the source, the destination, the direction of the transfer (reading from the I/O device or writing to the I/O device), the size of the transfer unit, and/or the number of bytes to transfer in one burst. To carry out an input, output or memory-to- memory operation, the host processor initializes the DMA controller with a count of the number of words to transfer, and the memory address to use. The CPU then commands the peripheral device to initiate a data transfer. The DMA controller then provides addresses and read/write control lines to the system memory.
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Although the model could easily recover from any type of initialization, for example by choosing a set of random values, it is convenient to get an accurate background estimate as soon as possible. Ideally a segmentation algorithm would like to be able to segment the video sequences starting from the second frame, the first frame being used to initialize the model. Since no temporal information is available prior to the second frame, ViBe populates the pixel models with values found in the spatial neighborhood of each pixel; more precisely, it initializes the background model with values taken randomly in each pixel neighborhood of the first frame. The background estimate is therefore valid starting from the second frame of a video sequence.
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This is accomplished by jumping on a Koopa Troopa, picking up its shell, and then throwing it at other enemies to defeat them. Levels consist of two planes, a "foreground" and a "background", with lower, middle, and upper floor on each plane, and four pipes connecting different combinations of planes and floors. Some enemies can be defeated with Mario throwing a shell at an enemy on the same plane as himself, while others can only be defeated if Mario throws a shell at an enemy into the background from the foreground, or vice versa. The game's sole usable item is a mushroom, which, when touched, initializes "Fever Time", where Mario's shell throwing defeats any enemy it touches, regardless of its defenses.
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In both C# and Java, an object's fields can be initialized either by variable initializers (expressions that can be assigned to variables where they are defined) or by constructors (special subroutines that are executed when an object is being created). In addition, Java contains instance initializers, which are anonymous blocks of code with no arguments that are run after the explicit (or implicit) call to a superclass's constructor but before the constructor is executed. C# initializes object fields in the following order when creating an object: # Derived static fields # Derived static constructor # Derived instance fields # Base static fields # Base static constructor # Base instance fields # Base instance constructor # Derived instance constructor Some of the above fields may not be applicable (e.g. if an object does not have static fields).
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Let minL be a pointer that points to the minimum element in the doubly linked list L, c_{x_0} be the minimum element stored in the 2–4 tree, T, k be the number of elements stored in T, and n be the total number of elements stored in queap Q. The operations are as follows: New(Q): Initializes a new empty queap. : Initialize an empty doubly linked list L and 2–4 tree T. Set k and n to zero. Insert(Q, x): Add the element x to queap Q. : Insert the element x in list L. Set the bit in element x to one to demonstrate that the element is in the list L. Update the minL pointer if x is the smallest element in the list. Increment n by 1.
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ArtSbot (Art Swarm Robots), 2003, comprise several small autonomous robots, called Mbots, each equipped with color detection sensors, obstacle avoidance sensors, a microcontroller and actuators, for locomotion and pen manipulation. Mbots have two distinct behaviors: the random behavior that initializes the process by activating a pen, based on a small probability (usually 2/256), whenever the color sensors read white; and the positive feed-back behavior that reinforces the color detected by the sensors, activating the corresponding pen (since there are two pens, the color circle is split into two ranges - 'warm' and 'cold'). With this process the collective set of robots generate compositions where from a random background some color clusters emerge. RAP (Robotic Action Painter), 2006, work alone but based on the same principles of emergence and stigmergy.
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Second-stage boot loaders, such as GNU GRUB, rEFInd, BOOTMGR, Syslinux, NTLDR or BootX, are not themselves operating systems, but are able to load an operating system properly and transfer execution to it; the operating system subsequently initializes itself and may load extra device drivers. The second- stage boot loader does not need drivers for its own operation, but may instead use generic storage access methods provided by system firmware such as the BIOS or Open Firmware, though typically with restricted hardware functionality and lower performance. Many boot loaders (like GNU GRUB, Windows's BOOTMGR, and Windows NT/2000/XP's NTLDR) can be configured to give the user multiple booting choices. These choices can include different operating systems (for dual or multi-booting from different partitions or drives), different versions of the same operating system (in case a new version has unexpected problems), different operating system loading options (e.g.
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In all computers, software instructions control the physical hardware (screen, disk, keyboard, etc.) from the moment the power is switched on. In a PC, the BIOS, pre-loaded in ROM on the main board, takes control immediately after the processor is reset, including during power-up, when a hardware reset button is pressed, or when a critical software failure (a triple fault) causes the mainboard circuitry to automatically trigger a hardware reset. The BIOS tests the hardware and initializes its state; finds, loads, and runs the boot program (usually, but not necessarily, an OS loader); and provides basic hardware control to the software running on the machine, which is usually an operating system (with application programs) but may be a directly booting single software application. For IBM's part, they provided all the information needed to use their BIOS fully or to directly utilize the hardware and avoid BIOS completely, when programming the early IBM PC models (prior to the PS/2).
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DL may contain the drive number, as used with INT 13h, of the boot device. SS:SP points to a valid stack that is presumably large enough to support hardware interrupts, but otherwise SS and SP are undefined. (A stack must be already set up in order for interrupts to be serviced, and interrupts must be enabled in order for the system timer-tick interrupt, which BIOS always uses at least to maintain the time-of-day count and which it initializes during POST, to be active and for the keyboard to work. The keyboard works even if the BIOS keyboard service is not called; keystrokes are received and placed in the 15-character type-ahead buffer maintained by BIOS.) The boot program must set up its own stack, because the size of the stack set up by BIOS is unknown and its location is likewise variable; although the boot program can investigate the default stack by examining SS:SP, it is easier and shorter to just unconditionally set up a new stack.
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At this point WHDLoad performs its main task of switching off the AmigaOS operating system, disables multitasking and interrupts, and copies memory regions which are used by AmigaOS and required by the installed program to an unused place until the AmigaOS is needed again. WHDLoad also degrades the graphics hardware to OCS on original Amiga machines (this function actually can work also on emulated Amigas, but only on newer versions of WinUAE which recognizes WHDLoad and preserves its interrupts), then WHDLoad initializes all hardware with defined values and jumps into the Slave interface required for the program in question. The Slave interface loads the main executable of the installed program by calling a WHDLoad function (resload_DiskLoad or resload_LoadFile), then patches the main executable (so that the loaded program will be capable of loading its data stored into the hard disk via the Slave, in order to fix compatibility problems, and to enable an exit from the program) and calls the main executable. At this point the program that has been installed can perform the task for which it has been written, loading its data as it would from a real floppy disk.
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