Re: Question about //e serial ports

[sbennett@gnh-starport.cts.com (Stephen Bennett)]

morton@ceres.fccc.edu (Dan Morton) writes:
> I'd like to hook up a modem to a //e.  The //e
> currently has a serial printer connected to a
> super serial card.  My questions are:
>
> 1) Is there any problem using this card for
>    a modem connection?
 
It'll work fine, as long as you have the settings correct (see below) and
the proper cable (same)  :)
 
> 2) Does the port support 9600 baud (I have
>   a Concord Data Systems modem)?
 
Yup, it will:  Here's how to set it.  There's a black jumper block on the
right side of the SSC as you look at the components.  This is how you switch
it between use for a modem or printer.  Pull out the jumper, and put it in
so that the point of the triangle is pointing UP (there should be the word
MODEM over the block) instead of down (where the SSC should say TERMINAL).
You also need to move switches 1-5, 1-6 and 1-7 to ON, and 2-7 to OFF.
(There are two types of switches that have been used on the SSC.  If you
have rocker switches, the switch is ON when the top of the switch is pushed
in.  If you have sliding switches, the switch is ON when the switch has been
slid to the top.)
 
> 3) How do you select the speed?
 
Switches 1-1 through 1-4 are for the baud rate settings.  For 9600 baud,
you should set them as:  1-1 through 1-3 OFF, 1-4 ON.
 
Other switch information you may need is:
 
Switch 2-1 should be set ON for 1 stop bit, OFF for 2 stop bits.
 
Switch 2-2 should be set ON for 8 data bits, OFF for 7 data bits.
 
Switches 2-3 through 2-4 control parity bits.  For parity to be Even, set
both 2-3 and 2-4 OFF, for parity to be Odd, set switch 2-3 ON and switch
2-4 OFF, and for No parity, set 2-4 ON (and switch 2-3 is ignored).
 
  For most communications uses, you can set switches 2-1 through 2-4 ON
for N,8,1 parity and data bits...  This may be different for your
particular communication program, you'll have to see.
 
Switch 2-5 should be set ON to automatically generate LF after carriage
returns, OFF otherwise (I believe that you'll want this to be OFF).
 
Switch 2-6 controls forwarding of interrupts to the Apple II.  I believe
that this should be set to OFF for the //e, so that interrupts won't be
forwarded to the computer.
 
> 4) What are the pinouts?
 
It's a standard DB-25 connector, and if you've switched the jumper, that has
the effect of having switched the Transmit Data and Receive Data pins (pins
2 and 3, as I recall) that's normally done in the modem cable, so you can
use a standard straight through DB-25 cable, probably the same one as you
were using to the printer, if I remember all of this correctly (It's been
awhile since I've done much with SSCs, but this should be correct).
If I'm incorrect about the cable, I'm sure someone will correct me, I'm
pretty sure everything else is correct...  :)
 
> ----------------------------------------------------------------------------
> Internet:    morton@fccc.edu            Fox Chase Cancer Center
> Phone:       (215) 728-3633             7701 Burholme Ave
> Fax:         (215) 728-2513             Philadelphia, PA 19111
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