Re: Zlink Block Error Problems.

[Phoenyx <quazar@dcnet2000.com>]

Note: This message is a bit (lot?) longer than the average. I am
trying to offer as many possibilities as I can to help resolve this
problem. Much of these come from prior experience and/or various
references and passed along to you based upon, once again, my own
personal experience.

I am probably posting info which may have been addressed by others
(and maybe me) but I'm compiling the various possibilities as I
think of them.

It has been my experience that the Apple II systems have always been
notorious for finicky serial setups. This is further compounded by
the lack of any real serial connection standards on the various
Apple II models.

Sometimes, what you think should work, will not and what you think
won't work, will. This is even mentioned in my 2c technical
reference manual.

There is very little you can do but tinker with things. To ease this
tedious tinkering, I suggest you set the PC to the protocols you
will be using and try to make the Apple match these. I suggest to
use the standard 8-n-1 and make sure on the PC side, you are
actually setting the hardware level ports from the control panel
system applet.

Something else comes to mind. On the PC, do you have a serial mouse?
What comm port are you using and is it being shared with any other
hardware? A definite no-no when dealing with communication.



Rubywand wrote:
> 
>      Being able to do PC-->A2 disk image transfers with ADT validates a lot of things about your hardware setup.
> 

This may not be quite true. ADT does very little error correction
or testing and what it does do is simple verification of the block
of data. I haven't looked at the source for quite some time but I
think it is a simple checksum method. The program is very forgiving
of the cable setup. I have used a simple 2 wire connection on my 2c
and ADT transferred disk images quite easily. Of course, this was
when I was constructing the cable and I copied a disk image of the
ADT disk and utilities. It also sent the ADT code for the Apple at
300 baud which was really slow. There is more about this else where
in this message.

When finished, the cable was a true null modem to facilitate comm
program connections. As I mentioned in another message in this
thread, I use Proterm. For the most reliable connections, I suggest
you purchase it. It is much more user friendly and the latest
versions are even better than the one I use.

Proterm has an actual null modem setting which you can configure
for the system. This is the setting I use. I don't have the actual
link, perhaps someone will supply it for you. 

Another (unmentioned) option is using 'Apple Oasis' and transfer
files via emulator to Apple. This is a very stable method since it
uses the built in serial ports in the Windows system. This utility
and the disk server were created for a IIe with SSC and offers a
unique method for Apple II communications and file transfers.
Teodor even includes the cable setup info in the doc's.

The disk server transfers through the joystick port on the II to
the parallel port on the PC.

The 'slink' system is a set of a programs which run Apple to Apple
It was originally created for those who can't use the disk server
method. It can also run Apple to emulator, which must have a
reliable set of serial routines. I suggest the Oasis emulator. :)
It can also execute emulator to Apple, depending on your needs.
You set one side as a server and the other as the client.

The client software patches itself into the slot 6 space which
causes the floppy disks access to fail. In this case, you should
make the Apple II (real Apple II?) the server and connect the
server's floppy disk drives to the Oasis emulator. Essentially,
you will be using the real Apple floppy drives for 5.25 i/o. AFAIK,
this should work for Prodos disks and standard Dos 3.3 disks. All
others such as copy protected disks or modified Dos disks or 13
sector disks probably won't work. I haven't tested these other disk
possibilities since I have not found the need for this. Of course
all this works better with a larger storage media. :) As an added
enhancement, the (included) disk manager program can transfer files
between disk images and Windows/Dos disks. Well at least the hard
disk.

Here is where setting the actual hardware port in Windows is
needed. It must be set to match the settings of the super serial
card. Rather, the SSC must be set to match the PC.

A check of the cable should also be done. It should be a shielded
cable. It should be a true 'null modem' link. This means either a
standard serial cable with a null modem adapter or a custom
null modem cable. It is very easy to create such a cable and the
parts are available at most Radio Shack stores. For the novice
or those who don't feel like soldering, I suggest you get the
crimp on cable connectors pins as they work very well. Personally,
I prefer the cable method myself. This way I know it is what I
need and there are only two connections, real simple.

Someone here has also mentioned using ADT with a straight serial
cable without null modem. I haven't tested this and if I remember
correctly, the SSC settings are different. Which brings up another
possibility. Is the modem/terminal block set to the right type
of connection. This is a rectangular 'chip like' jumper which has
a triangle pointer which you use to know what it's set for. Pointing
up (top of card) is modem mode and down is terminal mode.

Most likely, the max baud rate should be 9600 as the 1 mhz cpu
can't cope well with faster speeds. Also many of the comm
programs are designed to only work at 2400 bps or less due to
this cpu bottleneck.

You may want to try sending the ADT file as a text transfer. If I
remember correctly, that's how I transferred it. If you are sending
the Apple part of ADT, you must transfer it at 300 baud. This is
caused by the speed with which the Apple II monitor (rom, not the
screen :) ) handles interpreting incoming data at faster speeds.
I.E. very slowly!

-- 

Thank you for your time and interest. I hope it was helpful
or at least interesting.

Phoenyx,

Apple2 user since March 1984

Links to Phoenyx's pages:
preferred..... http://zip.to/Phoenyx_A2
alternate..... http://www.tinyangeldesigns.com/Apple2