PCI Interrupts

When the interrupt originates from a PCI device, the level is not fixed in the hardware but is configured at PC setup time. To be able to handle such interrupts with flexibility, INtime includes a PCI support library (pcibus.lib) with several functions (see pcibus.h). The example shown is the function PciFindDevice. Given a vendor and device ID number, it fills in the structure including the interrupt level.

For details see the help file and the knowledge base. Note that the INtime RT Process wizard can generate PCI interrupt handling code. We strongly recommend using the wizard.

The returned interrupt level (dev.byIntLine) is then used as part of the parameter wLevel in the interrupt related functions – it is slightly different for shared, and message signaled interrupts.

Note: when a PCI device is installed in the system, Windows will detect it and install a device driver for it. To allow INtime to use such a device, it must be passed to INtime using the INtime Device Manager.