NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/sys/amiga/hardware-part1/7152

Internet Message Format | 1996-08-05 | 6.9 KB

Path: coranto.ucs.mun.ca!gnoel
From: [e-mail] (George Noel)
Newsgroups: comp.sys.amiga.misc,comp.sys.amiga.hardware,comp.sys.cbm
Subject: Re: Modem problems/prices (was AT Surfer Package)
Date: 14 Mar 1996 17:20:42 GMT
Organization: Memorial University of Newfoundland
Sender: [e-mail]
Message-ID: <4i9kha$[e-mail]>
References: <[e-mail]> <4i4c1o$[e-mail]> <4i5e32$[e-mail]> <4i6t37$[e-mail]>
NNTP-Posting-Host: plato.ucs.mun.ca
Summary: Someone else straighten this guy out.. he won't listen to me!
Keywords: High speed modems on multiple computer types

I have added comp.sys.cbm to this thread so Byron can be associated with some
other C64 owners/enthusiasts whom are also in the know, to show Byron he
isn't.

In article <4i6t37$[e-mail]>,
Byron Montgomerie <[e-mail]> wrote:
>George Noel ([e-mail]) wrote:

>: have long since stopped using it as I had sold it once I got a true RS-232
>: port and RS-232 modem.  I regret selling it now as I could have kept it
>: for my second C64 - it truelly was the best C64 specific modem out there.

Before RS-232 ports (true) were available on the C64, there was the C64
specific modems such as the Commodre 300 (1650) and 1200 (1670) modems and
then a third party Aprotek 2400 baud Mini-Modem all of which relied on the
inbuilt RS-232 routines of the C64 which were flaky.  People never even thought
2400 baud was possible on the C64 back then.  You could also buy third party
adapters such as the Centronix adaptor which plugged into the cassette drive
port so you could use true RS-232 modems on the C64 also but anything over
2400 baud would be unreliable. Then came the following option:

>I was thinking of this CMD port when I mentioned it, with a 1 Mhz c64 it can

What you refer to as the "CMD port" is actually the Swiftlink RS-232
cartridge which plugs into the cartridge/expansion port of the C64.  This
cartridge gives the C64 a true RS-232 port and a buffered UART inside of it.
This is the same port and UART used in various PCs.  It is being put out
by Creative Micro Designs and allows the C64 to use any standard RS-232 modem,
even the ones coming out today. What the cartridge does is buffer the
information coming in until the C64 tells it that it is ready to receive more
to be displayed to the screen.  You were talking about the Aprotek 2400 baud
Mini Modem and a few problems that I had with it as being the reason I was
so "biased" as you put it towards modem problems of today with certain modem
types not connecting properly with each other or staying connected.  The
problems I had with it was only with my BBS as the author of my software had
the transmit and receive timers based on his modem and the timers needed to
be adjusted for mine.  I did that and it worked fine.  It also worked fine
from the start with my terminal program.  I haven't had any trouble with the
RS-232 modem(s) except for some of the different standards of today and
settings of their modems caused connection problems with my RS-232 modem
due to their older chipsets and/or software versus hardware compression/
flow control and/or error correction enabled/disabled.  I was only basing
my opinions on this topic from the experience I had with RS-232 modems and
others connecting with me, other BBSs and the Internet. As said before certain
brand names trim the communications guidelines to get their lower price and
some offer software instead of hardware compression, error correction etc.
which causes a conflict when connected to hardware controlled ones.

>only handle 9600 with video dma turned off.

Only 9600 baud? I don't know where you got that from!  This just goes to
show you do not fully know what you are talking about.  It is a standard
RS-232 port that the cartridge provides so the C64 can use any modem the PC,
Amiga, MAC or whathaveyou can use as long as it is external.  This ranges from
2400 baud upto 38.8 bps.  Another company puts out the HART cartridge which
provides a better UART and lets the C64 go upto 56.6 bps (if your telephone
lines can handle it). :)  The only thing I have ever seen that attempted
to turn the video DMA off was the author of my C64 BBS software which did
that as an attempt to speed up the transfers from the C64 to the floppy and/or
hard drives if a high speed user was on - he was using 9600 baud himself.
With most of the screen blanked, it raised the CPS rates slightly but it
wasn't significant enough for him to keep it in.. he found another means
of increasing the speed anyways.  The writing to the disk drives slowed down
the CPS rates and some was lost also due to the Mhz of the C64 but the modem
still functioned properly and didn't cause any connection problems
resulting from this.  With terminal programs, outputting to the screen
doesn't cause a slowdown, only if you are downloading/uploading (when the
drives get wrote to or read from) and they increased the speed by triple/
quadruple buffering techniques such as Novaterm uses.  This is the same or
similar problem in 7.15 MHz Amigas with high speeds - the standard
serial.device needs to be upgraded to make it more stable by using such
things as the (baudbandit).device and with speeds over 14.4k, a higher
processor such as an 020 is recommended/needed to achieve full CPS rates.
You cannot blame such problems only on the C64 and you cannot say my knowledge
of modems is biased because I use an RS-232 modem on a C64, it is standard
throughout, no matter what computer you have it on when it comes to
settings, and connections with other modems.

>: >only v.fast or use proprietary compression schemes and if you want to avoid
>: >them all you have to do is ask before you buy.
>
>: For those in the know yes, but a lot of people only see the cheaper price
>: and see 14.4k and/or 28.8K and think everything is fine but don't read
>: the small print.  I am basing my opinions on people's trouble connecting
>
>Find me a new 14.4 modem that isn't v34.

V34/V34bis was the point I was trying to make.. hardware or software
controlled?  That makes the difference on price and performance.  Compare
some Zoom and Zoltrix brand name modems to USR modems (Besides the USR
14.4k SI which is software controlled).  You will find a lot of people
have it against these brands and much prefer USR modems.

>The c64 is a 1Mhz machine, it was designed that way, I don't blame it for not
>being able to handle todays modems. :)  You have been reading between the lines
>vertically again I see. :)

Make jokes all you want, the joke is only on you.. you do not need the top
of the line computer to have experience with these types of modems and
connection problems with other no name brand names and/or different
settings.

>Regards,
>
>BM

-=*George*=-

P.S. Byron should worry about what *type* of modem or brandname is included
with Amiga Technologies Surfer/Walker pack rather then which computer
High Speed modems can be used on.