.TH cxy 4.SH Namecxy \- CXY08 communications interface.SH Syntax.B "device dhu0 at uba0 csr 0160440 flags 0x?? vector dhurint dhuxint".SH Description.NXR "CXY08 communications interface"A CXY08 provides eight communication lines with modem controladequate for UNIX dialup use. The device behaves and looks justlike a DHV11 and is specified in the configuration line the sameas a DHV11 device.Each line attached to the CXY08 communications interfacebehaves as described in.MS tty 4and can be set to run at any of 16 speeds. See.MS tty 4for the encoding..PPBit.I iof flags can be specified for a .PN cxydevice to say that a line is not properlyconnected and that the line should betreated as hardwired with carrieralways present.Thus, specifying flags 0x04 in the specification of .PN dhu0would cause line tty02 to be treated in this way..PPThe .PN dhu driver normally interrupts on each input character..NTThe .PN cxa ,.PN cxb ,.PN cxy ,.PN dhv ,and .PN dhqdevices operate under the control of the .PN dhu driver..SH Diagnostics.B "dhu%d: receive fifo overflow.brThe character input fifo overflowedbefore it could be serviced.  This can happen if a hard error occurswhen the CPU is running with elevated priority, as the system then prints a message on the console with interrupts disabled.This can cause a few input characters to be lost to users.It is not serious..PP.B "dhu%d:%d DMA ERROR.brA DMA transfer error has occurred.The.PN cxyunit number and line number are printed.This means that the channel indicated has failed to transfer DMA datawithin 10.7 microseconds of the bus request being acknowledged or thatthere is a memory parity error.This may cause a few output characters to be lost..PP.B "dhu%d: DIAG. FAILURE.brThis indicates that the.PN cxyinternal diagnostics have detected an error..PP.B "dhu%d: DHU HARDWARE ERROR.  TX.DMA.START failed".brThe .PN cxy failed to clear the start bit.  Normally, this is cleared to signal that a DMA transfer has completed..SH Files.TP 15.PN /dev/tty??.TP.PN /dev/ttyd?Dialups.SH See Alsotty(4), MAKEDEV(8)