.TH UN 4V "26 March 1982" .UC 4 .SH NAME un \- Ungermann-Bass interface .SH SYNOPSIS .B "device un0 at uba0 csr 0160210 flags 99 vector unintr" .SH DESCRIPTION The .I un interface provides access to a 4 Mb/s baseband network. The hardware utilizes a standard DEC DR11-W DMA interface in communicating with the host. The Ungermann-Bass hardware incorporates substantial protocol software in the network device in an attempt to offload protocol processing from the host. .PP In configuring a .I un the flags value is used to define the network to which the interface is attached. The host's address is discovered during auto-configuration by communicating with the interface. This driver supports only the Internet address format. .SH DIAGNOSTICS .BR "un%d: can't initialize" . Insufficient UNIBUS resources existed for the device to complete initialization. Usually caused by having multiple network interfaces configured using buffered data paths on a data path poor machine such as the 11/750. .PP .BR "un%d: unexpected reset" . The controller indicated a reset when none had been requested. Check the hardware (but see the bugs section below). .PP .BR "un%d: stray interrupt" . An unexpected interrupt was received. The interrupt was ignored. .PP .BR "un%d: input error csr=%b" . The controller indicated an error on moving data from the device to host memory. .PP .BR "un%d: bad packet type %d" . A packet was received with an unknown packet type. The packet is discarded. .PP .BR "un%d: output error csr=%b" . The device indicated an error on moving data from the host to device memory. .PP .BR "un%d: invalid state %d csr=%b" . The driver found itself in an invalid internal state. The state is reset to a base state. .PP .BR "un%d: can't handle af%d" . A request was made to send a message with an address format which the driver does not understand. The message is discarded and an error is returned to the user. .PP .BR "un%d: error limit exceeded" . Too many errors were encountered in normal operation. The drive will attempt to reset the device, desist from attempting any i/o for approximately 60 seconds, then reset itself to a base state in hopes of resyncing itself up with the hardware. .PP .BR "un%d: restarting" . After exceeding its error limit and reseting the device, the driver is restarting operation. .SH SEE ALSO intro(4N), inet(4F) .SH BUGS The device does not reset itself properly resulting in the interface getting hung up in a state from which the only recourse is to reboot the system. .PP The driver is untested with 4.1c.