USR Courier V.Everything Modem Settings

The accuracy or usefulness of these settings have not been verified. They were provided by a reader who says they work for him, and are provided here as a public service.

These settings were sent to us by Doug Hughes.

We (Auburn University College of Engineering) have a bunch of USR Couriers hanging off a Sparc 2 with an Aurora SBUS 16 port serial expansion port acting as a PPP/login server. If you don't have an expansion board you'll be limited to 38400 baud rate. We use agetty instead of regular getty, but the setup is pretty much the same. Here is our register and switch list (for a Sportster it would be slightly different.)

This list prepared using ati4

USRobotics Courier V.Everything Settings...
    B0  C1  E1  F1  M1  Q0  V1  X7
    &A3  &B1  &C1  &D2  &G0  &H1  &I0  &K3  &L0  &M4  &N0
    &P0  &R2  &S0  &T5  &X0  &Y1  %N6  #CID=0

    S00=003  S01=000  S02=043  S03=013  S04=010  S05=008  S06=002  S07=060
    S08=002  S09=006  S10=007  S11=070  S12=050  S13=000  S14=001  S15=000
    S16=000  S17=000  S18=000  S19=000  S20=000  S21=010  S22=017  S23=019
    S24=150  S25=005  S26=001  S27=000  S28=008  S29=020  S30=000  S31=000
    S32=005  S33=000  S34=000  S35=000  S36=000  S37=000  S38=000  S39=000
    S40=000  S41=000  S42=126  S43=200  S44=015  S45=000  S46=000  S47=000
    S48=000  S49=000  S50=000  S51=001  S52=000  S53=000  S54=064  S55=000
    S56=000  S57=000  S58=000  S59=000  S60=000  S61=000  S62=000  S63=000
    S64=000  S65=000  S66=000  S67=000  S68=000  S69=000  S70=000

These settings work for both dial-in and dial-out on a SunOS machine. The settings should not change for Solaris2.X either. On the host side make sure that you have the rts/cts kernel patches installed (see for patch information). Also, on SunOS make sure you do a ttysoftcar -n /dev/ttyx (where x is the tty device of the modem, typically 'a' or 'b') to enable hardware flow control before enabling your gettys in the ttytab.

Most of the switches above are factory defaults. Below I'll list which ones I have changed and why.

Dip switch #5 should be set to on. Without this you won't get auto answer.

ats0=3 auto answer on second ring. This somewhat foils modem war-dialers by making the time it takes to find a modem longer

at&k3 This enables V.42bis only, disabling MNP5. I feel this is safe these days. MNP5 can make some file transfers longer on already compressed data.

ats32=5 Auto Answer on/off toggle (used in conjunction with dip switch #5)

ats51=1 Disable MNP/V.42 negotiation at 1200 baud. Nobody has V.42 at 1200 anyway, so why waste time negotiating it. Some may want to set ats51=3 to disable it for 2400 too. However, there are still people using old Microcom modems at 2400 with MNP (I have one for instance, but seldom use it)

Further notes: Courier V.everything has support for MNP10, but there is no special register, switch, or setting for it. If you have a very noisy link (as I sometimes do) it can be helpful to set your client modem in MNP10 mode if that option is available and connect to the courier. Couriers work extremely well as server modems, but may not be as good for a user/home modem.

The Courier can be configured to handle Caller ID and distinctive ring answering. These functions are described in the addendum distributed in newer modems (with the pre-standard 33.6). If you did a firmware upgrade to get 33.6, you can get the addendum information from USR directly. I've only been able to find the firmware on their BBS and not their web site, but you'd think it'd be there somewhere...

Doug Hughes, Auburn University College of Engineering
Feedback: doug