Retronetworking

7-11-95

    UNIX & XENIX & Terminals & Other NON-PC-non-dos-based applications

        (including VAX, pay telephones, remote controller or other)

     The  defaults for the modem are &C0  &D0, autoanswer OFF. For 

most  PC applications  you  set  &C1   &D2.  Unix  and  Xenix  do  not  

seem  to  be standardized. Try combinations;  (AT&F sets defaults)

AT&F                AT&F&C1                  AT&F&D2

AT&F&C1&D2          (some rare cases may want &D3 - see manual)

     If  the  device cannot issue the init string to the modem  each  

time, finish  the line with &W and it will be saved to NV ram so the  

modem  will power-up with that configuration.

AT&F&C1&W    (example)

To set autoanswer to ON the command is S0=1     ATS0=1

     Commands  may  be combined on one line, AT&F at the start, &W  at  

the end.  The  modem will also 'wake up' at the same speed, parity,  

bits,  and stop bit that you were using at that time the AT.....&W 

command was issued. So  always  use  the fastest (19,200 or 38,400) 

that  the  modem  and  port support when you do the AT...&W.  CTS/RTS 

hardware flow control is  default and best. The &K command sets flow 

control (see the manual).

>>>  On some devices the &Rx (tracks RTS) and &Sx (tracks DSR) may 

need  to be changed from default (see your manual). DTR delay is 

controlled by  S25. *S38  can  be  increased  to keep the modem from  

hanging  up  due  to  DTR dropping.<<<

     Another  default is E1 (command echo). Many systems prefer not to  

get command  echos,  so E0 should be included in  the string.  To  get  

numeric responses instead of default word responses, change V1 to V0.

    *The %E2 will tel the modem to re-negotate the connection, 

(protocol  & speed) while on-line. %E3 also enables fast hangup.

    *If  you are having sending BREAK or BUFFER (getting  empty)  

problems, try \K0 through \K4 (see manual -  \K5 is default).

    In  working with one SCO Unix user these strings worked.

ANSWER  modem: AT&F&C1E0Q1S0=1 (&W)

calling modem: AT&FQ1S0=0      (&W)

     One Mini-computer user reports this works:

ANSWER  modem: AT&FE0&R1S0=1 (&W)   <-- note: these two had to change &R1

calling modem: AT&F&C1&R1    (&W)   <-- from default &R0

     The  &W also saves the 'current' speed, parity, bits and stop 

bit,  so the modem will wake-up with those defaults.

And a VAX DECSERVER-200 reports this works.. Modem Enabled, Dialup 

Enabled,   DSRLOGOUT Enabled, and DTR WAIT Enabled.

AT&F&C1&D3E0Q1&R1&S1S0=1

     The SUN system with a Systech MTI board requires a special cable  

(see you manual "Adding hardware to your system"). Following that 

diagram should be about 8 pages with information for setting the modem 

and the Unix.

     The  default for Zoom 'V' series modems is to use speed-buffering  

(on the  Turbo you need to set S36=7). This means you set your port  

at  19,200 when  you setup the modem. When you use the modem, the 

modem takes care  of modem-modem speed, buffering between the modem- 

computer.  To set BPS (often incorrectly  called  Baud),  you merely 

set the  terminal  or  software  in terminal  mode  at the BPS speed 

you want, and type AT to the  modem.  This simple  procedure also sets 

Bits, Parity & stop bit. If you want the  modem to 'wake up' at this 

BPS then type AT&W. The modem will stay at this BPS as long  as  the  

Terminal or software on the computer, does not  send  an  AT command 

at any other speed.

     To  'lock'  port  modem speed, set the port at  the  speed  you  

want. (19,200  is often best). Set the modem *ATS95=0 (default) and 

the  software may  then  either  be set to autodetect speed, or to  

turn  autodetect  OFF (best).  No matter what the carrier speed, when 

*S95=0, the modem will  say CONNECT  19200 (or CONNECT 9600 if that 

was what you set), so the  software will  not  issue  a command at the 

carrier speed, but only  at  the  pseudo CONNECT speed, effectively 

LOCKING the port and modem.

     When using in Syncronous mode, along with these suggestions, also  

see your modem manual section on Syncronous for some  Zoom modems. 

Most do  not have Syncronous mode.  When using &Q2 also include E0Q1 

in the same line.

     The  pins  are  standard  RS-232. While PC  cables  are  always  

25-25 straight  through  type  ( or 25-9pin), some  non-pc  may  need  

Null-modem cables,  where  pins 2/3 and 3/4 are swapped. They MUST  be  

hardware  flow control  cables, so an old cable from a 2400 modem may 

fail. On  2400  non-V modems only some of the pins 2-8 and 20 are used.

(* V-series/highspeed modems only)

_____________________________________________________________________

1-11-96                           Dumb Mode

     Like  Hayes,  all Zoom/modems are 'smart' modems and  are  'Hayes  

AT' compatible.  They cannot be turned into 'true dumb' modems.  

However,  they can  be  set to turn off certain responses which in 

most cases is  what  is actually required. Non V-Series modems highest 

register is S27. Settings can be Saved with the &W command. AT&W saves 

all current settings.

     DEFAULT settings are listed first.

E1 - echo commands being sent to the modem back to the computer

E0 - do NOT echo back commands

Q0 - sends modem responses back to the computer

Q1 - do NOT send back any responses

Q2 - Send back originating responses, do NOT send answering responses.

V1 - send responses as words

V0 - send responses as numbers

X4 - this command chooses which CONNECT BUSY (etc.) responses  are  

     sent  back to the computer. See the manual for other than X4.

&S0 - Force DSR ON

&S1 - sometimes needed in 'dumb'

The following may effect in some situation. * are V-series only

* N1 - connect at any speed           * &K3 - RTS/CTS flow control

  N0 - connect fixed speed              &K0 - none

                                        &K4 - Xon/Xoff

&C0 - DCD forced ON                     &K5 - transparent Xon/Xoff

&C1 - DCD follows carrier

                                      &R0 - tracks RTS signal

&D0 - does nothing w/DTR              &R1 - ignores RTS

&D2 - Hangs up on DTR drop

&D3 =  "    "  and resets             S0=0 - do not answer RING

                                      S0=1 - answer on 1 RING

                                      S0=2 - answer on 2 RINGS (etc)

One other thing may help. If the modem must not accept any commands, 

change register  S3. default is 13 for carriage return. Something like 

126 for the ~  char or 124 for the | char might be a good choice. Be 

Sure if  you  save the  change, to write it down so you can change it 

back later. If it was  ~ then  to change it back just type ATS3=13~  

and it will change back to  13. Most  Zoom/modems won't let you save 

register 13, so if you use  S3  you'll have to initialize the modem 

register 13 each time the modem is turned ON.

Check  your manual Appendix the &W command to see the list of commands 

the  modem  will save.

-----------------------------------------------------------------------

NOTE: We have only PCs and Macs to test modems and software at Zoom.  

While Zoom/modems  and  faxmodems  will work with  any  system,  

Zoom/modems  are furnished  for PCs and Macs with appropriate 

software. All the  information you  need to get your modem working in 

other environments is noted in  this document.  If you need further 

help with your system so you  can  implement these instructions, call 

your installer or system analyst.

                                   Don Hinds - Zoom Tech

-----------------------------------------------------------------------

Zoom's Webmaster, who uses a Zoom modem with Linux, adds the following

comments.  Much of this will apply to other PC-based Unix systems

(especially FreeBSD, which uses the same PPP code) as well as Linux.

The three common uses of a modem with Linux are:

1.  PPP connections with pppd

2.  Terminal communications with minicom or seyon

3.  Accepting dialup connections with getty

I will only address 1 and 2, since I have no experience with 3.

pppd will only let you specify modem port speeds up to 38,400.  If you're

using a 28.8 Zoom modem, you will definitely want a faster port speed;

115,200 if it works reliably on your system and your ISP uses that port

speed, 57,600 otherwise.  You get the higher speeds by running setserial

before starting pppd, like so:

setserial /dev/modem spd_hi (57,600)

setserial /dev/modem spd_vhi (115,200)

This assumes you have /dev/modem set as a symbolic link to your actual

modem device (/dev/cua0 or whatever).

In addition, you will want to use the crtscts option to pppd (makes pppd

do hardware handshaking), and set up the modem for hardware handshaking

(AT &C1 &D2).  A final trick that you'll need to know about if you connect

to an ISP that uses dynamic IP addresses and you also have an Ethernet;

add the noipdefault option to your PPP settings.  Otherwise, pppd may

try to use your Ethernet IP address for the PPP connection, instead of

the one from the ISP; the option forces pppd to get an address from the

ISP if possible.  Whether you have this problem or not depends on the type

of IP router your ISP uses.

minicom and seyon don't need any special tricks to work with Zoom modems.

Again, you'll want to enable hardware handshaking on the modem (AT &C1 &D2).

These terminal programs let you specify higher port speeds directly, unlike

pppd, so you don't need to use setserial.

Finally, a warning about the internal ComStar modem.  The ComStar is a

Plug and Play modem with no non-volatile memory for its communication port

settings.  In the DOS and Windows 3.1 environment, you run a utility called

PORTWIZ to set the modem to the port address and IRQ you want.  (Windows

95 has Plug and Play support built in, and sets up the modem automatically.)

To use a ComStar with Linux, you must first boot DOS, run PORTWIZ, then

use LOADLIN to start Linux.  I do not believe that you can run PORTWIZ from

DOSEMU.  We also do not currently know of any software that supports

the speakerphone features of the ComStar under Linux or any other version

of Unix.

The forthcoming external ComStar (shipping summer 1996) will be useable with

Unix systems with no problems; again, the speakerphone features are not

supported by any currently available software, but we will keep a lookout

for voice-capable software and make it available on our web site if possible.

webmaster@zoomtel.com