Bus IO Overview

RtGetBusDataByOffset, RtTranslateBusAddress, and RtSetBusDataByOffset facilitate the development of RTSS hardware drivers. Each function eases the gathering of specific hardware information and/or setting hardware.

RtGetBusDataByOffset is used primarily in support of attaching a driver to a hardware device. For example, by issuing a call to RtGetBusDataByOffset, a PCI bus can be scanned, detect a particular device, and then return the bus number where the device resides, the bus interrupt level, and interrupt vector.

Setting hardware is accomplished with a call to RtSetBusDataByOffset. This function is useful when device initialization requires clearing or setting of status registers, slot, and so on.

RtTranslateBusAddress is used to translate a device-specific memory address range into the logical address space of a driver.

Programming Example (Bus I/O)

See the Bus I/O Programming Example in the RTX Example Reference. The code fragment illustrates each of the Bus I/O calls in a PCI driver.