Search results
Results from the WOW.Com Content Network
BIOS interrupt calls perform hardware control or I/O functions requested by a program, return system information to the program, or do both. A key element of the purpose of BIOS calls is abstraction - the BIOS calls perform generally defined functions, and the specific details of how those functions are executed on the particular hardware of the system are encapsulated in the BIOS and hidden ...
The keyboard controller also handles PS/2 mouse input if a PS/2 mouse port is present. Today the keyboard controller is either a unit inside a Super I/O device or is missing, having its keyboard and mouse functions handled by a USB controller and its role in controlling the A20 line becoming integrated into the chipset's northbridge and then ...
IRQ 2/9 is the traditional interrupt line for an MPU-401 MIDI port, but this conflicts with the ACPI system control interrupt (SCI is hardwired to IRQ9 on Intel chipsets); [6] this means ISA MPU-401 cards with a hardwired IRQ 2/9, and MPU-401 device drivers with a hardcoded IRQ 2/9, cannot be used in interrupt-driven mode on a system with ACPI ...
MSI (first defined in PCI 2.2) permits a device to allocate 1, 2, 4, 8, 16 or 32 interrupts. The device is programmed with an address to write to (this address is generally a control register in an interrupt controller), and a 16-bit data word to identify it. The interrupt number is added to the data word to identify the interrupt. [1]
A hardware interrupt is a condition related to the state of the hardware that may be signaled by an external hardware device, e.g., an interrupt request (IRQ) line on a PC, or detected by devices embedded in processor logic (e.g., the CPU timer in IBM System/370), to communicate that the device needs attention from the operating system (OS) [7] or, if there is no OS, from the bare metal ...
Normally a character cell has 8 scan lines, 0–7. So, CX=0607h is a normal underline cursor, CX=0007h is a full-block cursor. If bit 5 of CH is set, that often means "Hide cursor". So CX=2607h is an invisible cursor. Some video cards have 16 scan lines, 00h-0Fh. Some video cards don't use bit 5 of CH. With these, make Start>End (e.g. CX=0706h)
In computing, keyboard interrupt may refer to: A special case of signal (computing) , a condition (often implemented as an exception) usually generated by the keyboard in the text user interface A hardware interrupt generated when a key is pressed or released, see keyboard controller (computing)
Each USB HID interface communicates with the host using either a control pipe or an interrupt pipe. Isochronous and bulk pipes are not used in HID class devices. Both IN and OUT control transfers are required for enumeration; only an IN interrupt transfer is required for HID reports. OUT interrupt transfers are optional in HID-class devices.