1.\" Copyright (c) 1983, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)hdh.4 8.1 (Berkeley) 06/05/93 7.\" 8.Dd 9.Dt HDH 4 vax 10.Os BSD 4.3 11.Sh NAME 12.Nm hdh 13.Nd 14.Tn ACC 15.Tn IF-11/HDH 16.Tn IMP 17interface 18.Sh SYNOPSIS 19.Cd "pseudo-device imp" 20.Cd "device hdh0 at uba0 csr 166740 vector hdhintr" 21.Sh DESCRIPTION 22The 23.Nm hdh 24device provides an 25.Tn HDLC 26Host 27.Pq Tn HDH 28interface to an 29.Tn IMP . 30It is normally used when participating 31in the 32.Tn DARPA 33Internet. The controller itself is not accessible 34to users, but instead provides the hardware support to the 35.Tn IMP 36interface described in 37.Xr imp 4 . 38The configuration entry for the 39.Tn IMP 40must also include the 41.Em pseudo-device 42as shown above in the 43.Sx SYNOPSIS . 44.Sh DIAGNOSTICS 45.Bl -diag 46.It hdh%d: not alive. 47The initialization routine was entered even though the device 48did not autoconfigure. This indicates a system problem. 49.Pp 50.It hdh%d: cannot get chan %d uba resources. 51Insufficient 52.Tn UNIBUS 53resources existed to initialize the device. 54This is likely to be a shortage of 55.Tn UNIBUS 56mapping registers. 57.Pp 58.It hdh%d: LINE UP. 59This indicates that both the 60.Tn HDLC 61and 62.Tn HDH 63protocols have declared the 64link to the 65.Tn IMP 66alive. 67.Pp 68.It hdh%d: LINE DOWN. 69This indicates that the link to the 70.Tn IMP 71has died. 72.Pp 73.It hdh%d: TIMEOUT. 74.It hdh%d: HOST DATA ERROR. 75.It hdh%d: IMP SEQUENCE ERROR. 76.It hdh%d: HOST SEQUENCE ERROR. 77These errors indicate that an 78.Tn HDH 79protocol error has been detected. 80.Pp 81.It hdh%d: cannot get supervisor cmnd buffer. 82This error indicates that an 83.Em mbuf 84could not be allocated to send a command to the 85.Tn IF-11/HDH . 86.El 87.Pp 88Any other error message from hdh%d: indicates a serious error 89detected by either the driver or the 90.Tn IF-11/HDH 91firmware. 92.Sh SEE ALSO 93.Xr netintro 4 94.Sh HISTORY 95The 96.Nm 97driver appeared in 98.Bx 4.3 . 99