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Device Drivers

RTIP-32 maintains a Device Table with points to device driver entrypoints and other device specific data. By default, the device table has only one slot for a single device. Use configuration value CFG_NIFACES to change the table's size. Other than hardware resources, RTIP-32 has no limit on the number of simultaneously opened devices.

Device drivers must be added to the device list at run time after xn_rtip_init has been called before the device can be opened with xn_interface_open_config, xn_interface_open, or xn_attach. For each supplied driver, a bind function is supplied which will add the corresponding driver to the device table. The bind functions accept an instance number as a parameter which is used to distinguish several instances of the same driver (e.g. two or more identical Ethernet cards in one computer). Each instance of the same driver must have incrementing instance numbers starting at 0.

The following drivers are available:

Function xn_interface_open_config and xn_interface_open are used to open a device after xn_rtip_init has been called. xn_interface_open_config supplies hardware resource information such as the IRQ and port I/O addresses to use for ISA devices. PCI devices are able to determine this information automatically. Function xn_attach is used to open a serial port device for PPP or CLIP connections.

For examples on initializing Ethernet devices, see the included Demo Programs.

Diagnostics and Callbacks

Recompiling RTIP-32 Driver Source Files