.\" SCCSID: @(#)ik.4	8.1	9/11/90.TH ik 4 VAX "" Unsupported.SH Nameik \- Ikonas frame buffer, graphics device interface.SH Syntax.B "device ik0 at uba? csr 0172460 vector ikintr".SH DescriptionThe.PN ikprogram provides an interface to an Ikonas frame buffer graphics device.Each minor device is a different frame buffer interface board.When the device is opened, its interface registers are mapped,by virtual memory, into the user processes address space.This allows the user process very high bandwidth to the frame bufferwith no system call overhead..PPBytes written or read from the device are DMA'd from or to the interface.The frame buffer XY address, its addressing mode, etc. must be set up by theuser process before calling write or read..PPOther communication with the driver is by ioctls.The IK_GETADDR ioctl returns the virtual address where the user process canfind the interface registers.The IK_WAITINT ioctl suspends the user process until the ikonas devicehas interrupted (for whatever reason \(em the user process has to setthe interrupt enables)..SH RestrictionsAn invalid access (for example, longword) to a mapped interface registercan cause the system to crash with a machine check..SH Files.PN /dev/ik