SIO2PC - The Next Generation
by David Davies
The SIO2PC has undergone a couple of redesigns since Nick
Kennedy's original design introduced the idea of using a PC as a slave for the
Atari 8-bit. The two-chip MAX-232 design was scaled down and replaced by a somewhat
cheaper and simpler to build single-chip design. Certainly, I
remember
experiencing several problems getting the original design to work a few years
ago, while a quick attempt to get the single-chip version working on a
breadboard a few weeks ago yielded immediate hook-up with my laptop.
The design for the single-chip version I built was taken
from the APE (Atari Peripheral Emulator) web site. The site also contained
details of how to build a similar (but incompatible) cable to allow you to
connect an original Atari 8-bit disk drive to a PC. With the APE ProSystem
software running on your PC and a drive like the 1050 hooked up, you can create
ATR files from your original disks. The ATR files can be loaded into just about
any Atari 8-bit emulator. An extra feature of ProSystem is backing up your copy protected disks. But more on that later.
A few weeks ago, while browsing the AtariAge discussion
board, I came across a few posts by the author of APE. At the bottom of his
posts there were links to new pages on his site. One link went to a page
giving details of his new flash ROM cartridges for the 8-bit and another gave access to a page with yet another version of the SIO2PC adapter.
Steve Tucker's new SIO2PC design is a combination of both the
single-chip SIO2PC and the ProSystem cable. A problem with having two separate
cables built is that plugging the wrong one into your Atari drive could
damage
it. Here is a solution that removes that worry as it will automatically switch
between APE and ProSystem mode as necessary.
The unit itself is professionally produced and presently
available in two versions. One includes a terminal block at one end to
allow you to connect a cannibalised SIO cable for attaching it to the Atari.
The other version, which is probably in limited supply, actually houses a
13-pin PCB-mounted SIO connector which allows you to use a normal SIO cable
between the device and the Atari. This is the version I got my hands on.
It is on a lacquered PCB
containing the usual 1489 chip, as used in the standard single-chip SIO2PC
design, and a GAL programmed logic chip. The rest of the board contains a
capacitor, two green LEDs, a red LED, a 9-pin serial socket for connecting to
the PC and a 13-pin SIO socket for connecting to the 8-bit. The red LED is a
power indicator and the two green LEDs indicate data transmission
across the device.
One of the main problems with the unit is that it ships
without any instructions, so it was pretty much a case of trial and error. In
the end it took me about two hours to work out the sequence in order to get it to
work properly.
One thing to remember is that the device doesn't take power
from the PC. Your Atari must be switched on for it to work. This might sound
obvious when using the APE software. However, it's not so obvious if you're
using ProSystem. Even though you're accessing the disk drive from your PC, you
still need the Atari connected to the drive and switched on to provide power.
The
SIO2PC should also be last in your device chain.
Something that many people might worry over is the fact that
the device is not protected by an external cover or case. The PCB and parts are
open to the world and may therefore be subject to damage from excessive
handling or electrostatic discharge from the user's hands or clothing. To some
extent the risks of such are over-hyped. Virtually all new semiconductors are
designed to withstand an electrostatic discharge of at least 10,000 volts.
But,
of course, it doesn't mean that you should start testing the SIO2PC with your
newly built stun gun!
So how well does it work? To put it into simple terms, it
does what it says on the box. With ProSystem running I was able to use the 1050
to back-up a protected Atari disk onto the laptop and then use APE to load it
back into the Atari. But I managed to hit a strange problem when creating ATR
format files with ProSystem. Most refused to load into APE yet they ran fine on
the Atari800Win Plus emulator. I contacted the author and he tested the
software and hardware on his system, but reported that they worked fine. It
may well be a testing issue but, let's face it, it's impossible to test every
possible PC configuration - you just have to hope that the software works. As
a case in point, a friend once bought me a copy of Populous: The Beginning
a few
years back. I couldn't get it to work on my system (blue
screen of death every time) although it was well within the recommended
specifications for the game.
Something that perhaps suggests a combination of issues
related to the new SIO2PC design and the hardware I've had it running on is the
fact that, although I didn't test it fully at the time, the original SIO2PC
cable I built on the breadboard seemed to work fine. APE allows automatic
configuration based on your hardware set-up. When the original design was
connected to the laptop, the configuration option worked flawlessly. Now, with
the new SIO2PC the PC completely locks up when I try to auto-configure.
However, I suspect that my problems may well be an isolated
incident. All in all, if you haven't already got your hands on an SIO2PC of one
form or another then Steve Tucker's version of the fabled cable is one well
worth considering. Although more expensive than a home-built unit it has the
advantage of being suitable for the SIO2PC software, APE and ProSystem.
But for
me the biggest advantage is that I don't have to slice up another much-needed
SIO cable. But if you want one which doesn't require butchering an SIO then you
may have to be quick to order one with a 13-pin SIO socket on the board as they
are in limited supply.
Verdict
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Name:
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New
SIO2PC
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Developer:
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Steve
Tucker
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Pros:
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-
Only one interface needed to use either ProSystem or APE.
- Little
risk of damaging your hardware with two seperate home-built interfaces.
- Reliable
operation once set up properly.
- No need to disect your own SIO cable
if you opt for the version with the female SIO plug.
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Cons:
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-
No instructions
(online instructions outdated and of little help).
- No
outer cover to prevent
possible damage from mishandling or ESD.
- APE/ProSystem
software unintelligent.
- Seemingly some compatibility
issues on some PC
systems.
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Rating:
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|
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