Re: Interfacing to parallel port dongle via USB adapter
- From: Jim Thompson <To-Email-Use-The-Envelope-Icon@xxxxxxxxxxxxxxx>
- Date: Wed, 02 Apr 2008 15:31:22 -0700
On Wed, 02 Apr 2008 17:07:49 -0500, Paul Urbanus
<urbpublic@xxxxxxxxxxx> wrote:
Paul E. Schoen wrote:
I have software (PADS Layout) that requires a parallel port dongle, and it
works fine on my present (fairly old) computer, which has a native parallel
port. But newer computers, particularly laptops, do not have these legacy
ports and instead use USB to Parallel (or USB to Serial) converters. They
generally work well for printers, but I have heard that they do not work
for dongles. The usual solution is to obtain a USB dongle from the software
vendor (www.mentor.com), but they require the user to be on "maintenance"
in order to get a USB dongle, and they impose outrageous penalties and
payment of back (unused) support in order to be reinstated.
I have some experience with USB using the Microchip PIC18F2450 series, and
I have a demo board that works nicely as a USB to Serial converter. But I
want to see if it is possible to emulate a parallel port via USB that will
be transparent to the software that interfaces with the dongle. I think the
problem with the commercially available USB-Parallel adapters is that they
work only for printer functions, and not for individual bit-banging, which
is what I understand is done with the dongle.
The PADS dongle I have is a Globetrotter FLEXid (www.macrovision.com). This
is a newer dongle than the one used for another software package that
interfaces to software (TCC) sold by my associate to work with my product,
the Ortmaster. When I researched that dongle, the Rainbow Technologies
Sentinel Pro, it described its operation as using only one or two lines of
the parallel port to send and receive streams of data. If the new dongle
works the same way, it seems that it should be possible to emulate this via
USB.
Info on this device:
http://www.macrovision.com/webdocuments/PDF/FLEXidDongle_faq.pdf. But it
does not give details on the hardware.
Some information I found is http://www.woodmann.com/crackz/Dongles.htm, but
this is a hacking site, and that is not what I want (although I'm tempted).
I'll probably check the parallel port signals with a storage scope to see
what pins are active when I'm running the software with the dongle, and
then I'll have a little more information. But if anyone has done any work
in this area, I'd appreciate a jump start.
TIA,
Paul
Unfortunately, I suspect you won't have any success attaching a security
dongle to a USB-to-parallel adapter. USB carries data in 1 millisecond
frames, except for high speed where 125 microsecond frames are used. And
any USB-parallel adapter will not be high speed, so the slower 1
millisecond packet timing will be applicable.
The parallel port hardware is mapped into the PC I/O space, and access
is not constrained on any descrete time boundaries. So, if the dongle
driver writes something to the dongle hardware and expects a response in
tens to hundreds of microseconds, it will be impossible for the
USB-parallel adapter to respond.
Your best bet is to purchase a PCMCIA/PCCARD parallel port adapter.
Although they are a bit pricey ($100+ USD), they *should* be a faithful
emulation of the hardware port. You might have to change the
port/interrupt addresses to match the legacy addresses of 378h/278h/3BCh
for the driver software to see the port (depends on how old your dongle
software is). For a desktop machine, you should still be able to buy a
PCI parallel port card for $30-$40 USD.
If you can reverse engineer your hardware key (and you are a legitimate
owner of the software), then maybe you could write a kernel level driver
that would emulate the parallel port. I'm a hardware guy and I don't
know diddly about writing kernel level drivers - so this last suggestion
may not be realistic. I have done some looking at dongle communication,
and they much more sophisticated than the old Xilinx days of the 'AA',
'AB', and 'AC' hardware keys, which were easy to duplicate (only
requiring some CMOS counters and gates).
Urb
I seem to recall some software from years ago that captured the signal
and responses to/from a parallel port dongle, then emulated it...
object: to avoid having a dongle hanging off the back of your laptop.
Perhaps it still lives?
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
America: Land of the Free, Because of the Brave
.
- Follow-Ups:
- Re: Interfacing to parallel port dongle via USB adapter
- From: Paul E. Schoen
- Re: Interfacing to parallel port dongle via USB adapter
- References:
- Interfacing to parallel port dongle via USB adapter
- From: Paul E. Schoen
- Re: Interfacing to parallel port dongle via USB adapter
- From: Paul Urbanus
- Interfacing to parallel port dongle via USB adapter
- Prev by Date: Re: Balanced filter -> Balun vs. Balun -> Single-ended filter
- Next by Date: Re: Interfacing to parallel port dongle via USB adapter
- Previous by thread: Re: Interfacing to parallel port dongle via USB adapter
- Next by thread: Re: Interfacing to parallel port dongle via USB adapter
- Index(es):
Relevant Pages
|
