[comp.sys.mac.programmer] MNP modems

tarr-michael@CS.YALE.EDU (michael tarr) (08/12/90)

Anyone out there have any experience getting a MNP-5 modem to connect
with a reliable link using white knight? Should WK be talking to the
modem at 9600 baud eventhough the modem should transmit over the line at
2400? Any tips. It is a practical peripherals 2400SA
-- 
/**************************************************************************
 * Mike Tarr                                    The Human Neuron Project  *
 * tarr@cs.yale.edu                             Department of Psychology  *
 * "My opinions are always my own."             Yale University           *

ngg@bridge2.ESD.3Com.COM (Norman Goodger) (08/28/90)

In article <25793@cs.yale.edu> tarr-michael@CS.YALE.EDU (michael tarr) writes:
>
>Anyone out there have any experience getting a MNP-5 modem to connect
>with a reliable link using white knight? Should WK be talking to the
>modem at 9600 baud eventhough the modem should transmit over the line at
>2400? Any tips. It is a practical peripherals 2400SA
>-- 
	WK really doesn't care whether your modem is using MNP or not
	its completely transparent to the terminal program. MNP is a 
	modem based hardware error correction protocol. For you to
	make use of it with WK, you need to read your modem manual to
	see what commands either turn it off or on, and what baud rates
	over 2400 might be supported between the Mac and the modem, while
	the modem initiates its highest link rate to the other modem.
	Of course the remote modem must also support MNP, for you to
	get MNP connections. In some cases with error correcting protocols,
	the overhead of MNP error correction can slow your file transfers
	down. So unless you have particularly noisy lines, you might not
	want to use MNP connections in all situations.
	.

-- 
Norm Goodger				SysOp - MacInfo BBS @415-795-8862
3Com Corp.				Co-SysOp FreeSoft RT - GEnie.
Enterprise Systems Division             (I disclaim anything and everything)
UUCP: {3comvax,auspex,sun}!bridge2!ngg  Internet: ngg@bridge2.ESD.3Com.COM

daven@svc.portal.com (08/29/90)

In article <25793@cs.yale.edu> tarr-michael@CS.YALE.EDU (michael tarr) writes:
>
>Anyone out there have any experience getting a MNP-5 modem to connect
>with a reliable link using white knight? Should WK be talking to the
>modem at 9600 baud eventhough the modem should transmit over the line at
>2400? Any tips. It is a practical peripherals 2400SA

You will probably want to setup WK to run at 9600 baud. Then turn on WK's
and the modem's hardware handshake, but only if you have a modem cable
that supports hardware handkshake. If not, then use Xon/Xoff in both WK
and the modem, but only if you're not going to use X/YMODEM.

Like all those "but..." clauses? If you can't meet either of the conditions
above (wrong modem cable, and need X/YMODEM) then you're better off staying
at 2400 bps.

Dave Newman


-- 
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Dave Newman - Sofware Ventures        | daven@svc.portal.com | AppleLink: D0025
Berkeley, CA  (415) 644-3232          | AOL: MicroPhone      | CIS: 76004,2161
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jsimon@voodoo.ucsb.edu (08/29/90)

-Message-Text-Follows-

In article <1990Aug28.181857.19878@svc.portal.com>, daven@svc.portal.com writes...

>You will probably want to setup WK to run at 9600 baud. Then turn on WK's
>and the modem's hardware handshake, but only if you have a modem cable
>that supports hardware handkshake. If not, then use Xon/Xoff in both WK
>and the modem, but only if you're not going to use X/YMODEM.

What about ZModem? Can you use MNP5 and software handshaking at the same
time?

russotto@eng.umd.edu (Matthew T. Russotto) (08/30/90)

In article <6180@hub.ucsb.edu> jsimon@voodoo.ucsb.edu writes:
>-Message-Text-Follows-
>
>In article <1990Aug28.181857.19878@svc.portal.com>, daven@svc.portal.com writes...
>
>>You will probably want to setup WK to run at 9600 baud. Then turn on WK's
>>and the modem's hardware handshake, but only if you have a modem cable
>>that supports hardware handkshake. If not, then use Xon/Xoff in both WK
>>and the modem, but only if you're not going to use X/YMODEM.
>
>What about ZModem? Can you use MNP5 and software handshaking at the same
>time?

If you have hardware handshake, either YModem (1K packets) or YMODEM-G (non-
error-correcting) will work fine, as will ZModem.  ZModem works even with
XON/XOFF.  

Hardware handshake allows you to go a bit faster, however, and it gives you
something to look at while uploading :-) (the lights on the modem blink on
and off)
--
Matthew T. Russotto	russotto@eng.umd.edu	russotto@wam.umd.edu
      .sig under construction, like the rest of this campus.