RS-422/485 Synchronous Serial PCMCIA Cards
FAQ
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I tried just looping data back to the adapter using a standard
COM Port null modem, why didn't it work?
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My SyncDrive(Plus) application is not working. How can I establish
that my hardware is configured properly?
-
Once I have determined using example programs that my hardware
is good, but my application program still doesn't work, what
should I do next?
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Under which OS is my RS-422/485 Synchronous Serial PCMCIA Card
supported?
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What are SyncDrive and SyncDrive Plus?
-
What are the major differences between SyncDrive and SyncDrive
Plus?
-
What is required to use SyncDrive and/or SyncDrive Plus?
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Which memory models does SyncDrive (Plus) support?
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What is the SyncDrive (Plus) Digital Phase-Locked Loop (DPLL)
used for?
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What are the data encoding requirements for using the DPLL?
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What are the clock speed requirements for the DPLL?
-
How does using the SyncDrive (Plus) DPLL affect the data rates
that can be achieved?
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Does SyncDrive (Plus) use the FIFOs in the optional Z85230
upgraded SCC?
-
What does the SyncDrive "error" indicator mean in a receive
com_block's buffer_status variable?
-
Why aren't there any SyncDrive example programs for buffer
queues using byte-synchronous communications?
-
Does the OS/2 version of SyncDrive work with version 4.00 OS/2
Warp?
-
Where can I find help with using my RS-422/485 Synchronous
Serial PCMCIA Card under OS/2?
-
Do I need local administrator rights to install a Quatech serial
device?
-
Should I disable the Toshiba laptop built-in infrared ports
in the system BIOS before installing my PCMCIA card?
-
My MPAP card appears correctly installed on my
laptop but it cannot communicate with my serial devices. What
should I do?
-
Will my Synchronous Serial PCMCIA card work under Windows 95/98/Me/2000/XP
that is controlled by a third party PCMCIA card services (Softex,
Card Wizard, etc.)?
-
Why are Quatech PCMCIA cards no longer supported under DOS?
-
I am using a computer that is running Card and Socket Services.
Can I still get the DOS drivers for my PCMCIA cards?
-
What does PCMCIA stand for?
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If I have problems not addressed in this FAQ, what information
do I need to submit on the technical support request form in
order to get help?
-
When installing a product, I get an error message stating "The System Cannot Find the File Specified." How can I fix this?
Q1. I tried just looping data back to the
adapter using a standard COM Port null modem, why didn't it work?
A. Null modems are intended for asynchronous adapters or
standard COM ports. They are not meant for synchronous communication
as with synchronous communication, the pinouts and signals are different
from asynchronous.
Q2. My SyncDrive(Plus) application is not
working. How can I establish that my hardware is configured properly?
A. A good step in determining whether a problem is related
to the software program or the hardware is to try known good compiled
SyncDrive(Plus) example applications on the hardware. Quatech provides
a set of example applications for both SyncDrive and SyncDrive Plus.
Q3. Once I have determined using example
programs that my hardware is good, but my application program still
doesn't work, what should I do next?
A. The answer to this question could be one of a great many
things depending on what the application is. The following are descriptions
of two of the most common problems our customers have experienced
over the last few years when writing application programs using
SyncDrive and SyncDrive Plus
Check the SyncDrive Configuration
This is usually a good place to start if the application program
is causing a crash or lockup. In particular, the customer should
double-check base_address, tx_interrupt, rx_interrupt, tx_dma_channel,
and rx_dma_channel.
Clock Sourcing
If the problem seems to be that transmit and receive functions aren't
functioning correctly, the programmer should double-check the clock_source
variable in the channel configuration structure. Also, be certain
that the modes in clock_source are set properly and check the hardware
manual to be certain that the clock signals are being routed to
the proper SCC outputs and inputs.
Q4. Under which OS is my RS-422/485 Synchronous
Serial PCMCIA Card supported?
A. View the latest OS
support matrix for RS-422/485 Synchronous Serial PCMCIA Cards.
Q5. What are SyncDrive and SyncDrive Plus?
A. SyncDrive and the new SyncDrive Plus are frame-level
synchronous communication driver packages written specifically for
use with C and are designed to aid users of Quatech MPA/MPAP/MPAC
hardware in the development of their application software.
Q6. What are the major differences between
SyncDrive and SyncDrive Plus?
A. There are three major differences between SyncDrive and
SyncDrive Plus.
- SyncDrive Plus is for Windows 2000/XP while SyncDrive is for
Windows 95/98/Me and OS/2
- SyncDrive Plus supports only bit-synchronous SDLC/HDLC protocols,
while SyncDrive supports both Bit-synchronous (SDLC/HDLC) and
byte-synchronous (monosync/bisync) protocols.
- SyncDrive Plus supports and is included free with MPAP series
PCMCIA cards and MPAC series PCI boards. SyncDrive supports and
is included free with the MPAP and MPAC series cards, as well
as Quatech's MPA series ISA boards.
Q7. What is required to use SyncDrive and/or
SyncDrive Plus?
A. SyncDrive requires a system with an Intel-compatible
80386 processor or later running Windows 95/98/Me or OS/2, SyncDrive
Plus requires a Pentium compatible processor, running Windows 2000
or Windows XP. Both require a C compiler. An import library that
resolves your applications' external references to SyncDrive(Plus)
functions is supplied in the DLL.
Q8. Which memory models does SyncDrive (Plus)
support?
A. DOS programs must be compiled in Large model. For Windows
95/98/Me/2000/XP and OS/2, programs are compiled in Flat model.
Q9. What is the SyncDrive (Plus) Digital
Phase-Locked Loop (DPLL) used for?
A. In configurations that do not include separate signals
for clocking information, it is sometimes possible to use the DPLL
to extract clocking information from the encoded data itself. There
are special requirements for the data encoding techniques and clock
speeds to be used with the DPLL. The DPLL can be used as the source
for the received data clock by making the appropriate bit selections
in the clock_source variable in the channel configuration structure.
Q10. What are the data encoding requirements
for using the DPLL?
A. SyncDrive (Plus) requires that the received data be either
NRZI (most common), FM0 or FM1 encoded. This choice should be made
in the operating_mode variable in the channel configuration structure.
The operating_mode selection affects both transmit and receive operations.
Q11. What are the clock speed requirements
for the DPLL?
A. The SCC always uses its internal baud rate generator
(BRG) as an input clock to "seed" the DPLL. The DPLL needs to oversample
the received data bit stream in order to extract clocking information.
This means that the DPLL's input clock needs to be running at a
multiple of the actual rate of the received data bit stream.
If the received data is NRZI-encoded, the DPLL input clock must
run at 32 times the received data rate. The clock_source variable
in the channel configuration structure must be set for X32 clock
mode. If the received data is FM-encoded, the DPLL input clock must
run at 16 times the received data rate. The clock_source variable
must be set for X16 clock mode.
Q12. How does using the SyncDrive (Plus)
DPLL affect the data rates that can be achieved?
A. The clock mode factors into the denominator of the equation
for calculating baud rate constants. As the clock mode increases,
the highest possible baud rate decreases. Running a X32 clock, for
example, will permit a substantially lower maximum baud rate than
would running a X1 clock. This is a tradeoff for using the DPLL.
Q13. Does SyncDrive (Plus) use the FIFOs
in the optional Z85230 upgraded SCC?
A. Yes, the FIFOs in the Z85230 are always used by SyncDrive
(Plus). The application does not need to enable them, and cannot
disable them.
Q14. What does the SyncDrive "error" indicator
mean in a receive com_block's buffer_status variable?
A. This bit will be set when a receive CRC error occurs
or when the receive buffer of the SCC itself suffers an overrun.
An overrun will occur when the SCC is not being serviced rapidly
enough. It is essentially a "horsepower" issue. Possible solutions
include lowering the data rate, using DMA if possible (SyncDrive
supports DMA only in the bit-synchronous mode), increasing the speed
of the host computer, etc.
Q15. Why aren't there any SyncDrive example
programs for buffer queues using byte-synchronous communications?
A. Actually, they do exist, and are available on request.
Please submit our Technical Support
Request form to obtain them. We don't distribute them because
they don't run well under DOS. The example programs do a lot of
printing to the screen with the "printf()" C runtime function call,
and the BIOS functions which handle this apparently disable interrupts
for long periods of time. This causes problems for buffer queues,
which are constantly generating interrupts as their operation runs
in the background. Using DMA reduces the number of interrupts substantially
and lets the bit-synchronous queue examples run better under DOS.
Unfortunately, this isn't an option for byte-sync modes. OS/2 and
Windows do not seem to suffer from the problem of printf() disabling
interrupts, and the buffer queue examples work even better under
those operating systems.
This is not to say that byte-sync applications cannot use buffer
queues. On the contrary, buffer queues should work fine in any application
so long as interrupts are not disabled for long periods of time.
Note that as SyncDrive Plus does not support byte-synchronous communication
protocols, there are no such examples available for it.
Q16. Does the OS/2 version of SyncDrive
work with version 4.00 OS/2 Warp?
A. Yes. The OS/2 version of SyncDrive works under OS/2 versions
2.1 up through 4.00. Users of this OS/2 version, however, should
have at least 16 M of memory before beginning to develop their SyncDrive
application.
Q17. Where can I find help with using my
RS-422/485 Synchronous Serial PCMCIA card under OS/2?
A. Though OS/2 is becoming increasingly less popular, Quatech
knows that there are many dedicated users out there, and we are
committed to continued support of OS/2. See our OS/2
tip sheet for answers to common questions about installation,
un-installation, configuration, and troubleshooting.
Q18. Do I need local administrator rights
to install a Quatech serial device?
A. Yes. When installing most kinds of hardware, you must
have local admin rights or equivalent on the PC. If your computer
is part of a Domain or participates in a networked environment,
please contact your local LAN Administrator for assistance.
Q19. Should I disable the Toshiba laptop
built-in infrared ports in the system BIOS before installing my
PCMCIA card?
A. Yes. Experience has shown that these infrared ports can
interfere with the proper installation of Quatech PCMCIA cards.
Once the installation is complete, these ports can be enabled again
without further problems
Q20. My MPAP card appears to have installed
correctly on my laptop, but it can't communicate with my serial
devices. What can I do?
A. Quatech's MPAP-200/300 is a 5V PCMCIA card and is known
to be incompatible with the new laptops listed below, all of which
do not provide enough power for the card. If you experience this
problem we suggest you contact your laptop manufacturer to determine
whether there is a voltage incompatibility with the MPAP. Note that
the entire MPAP line is currently being redesigned for 3.3V power.
Current list of laptops providing only 3.3V power that are incompatible
with the MPAP-200/300:
- Acer Travelmate 2200
- Compaq Presario X6000 series
- Compaq Mobile Workstation NW824
- Compaq NX9020
- Dell Inspiron 6000
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Fujitsu Lifebook N-Series
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HP ze4900
- HP DV1000
- Panasonic Toughbook CF-51 series
- Panasonic CF-72 series
- Panasonic CF-73 series
- Panasonic CF-M33
- Sony Vaio V505
- Toshiba Libretto 100
Q21. Will my Serial PCMCIA card work under
Windows 95/98/Me/2000/XP that is controlled by a third party PCMCIA
card services (Softex, Card Wizard, etc.)?
A. Quatech developed its drivers to work directly with the
ones found on the Windows operating systems. Enabling these original
Windows's drivers will provide quick and easy installation of all
Quatech's PCMCIA cards. We cannot predict how or if our cards will
function when used with other company's card services.
Q22. Why are Quatech PCMCIA cards no longer
supported under DOS?
A. Quatech DOS support for PCMCIA cards was built to work
with Card and Socket Services from System Soft. Newer laptops do
not use this software, and System Soft is no longer supporting it.
If you have a computer with Card and Socket Services installed you
should be able to use Quatech's cards under DOS. However, as there
is no longer any support for the program, we can no longer continue
to support our cards under DOS. Note that only SyncDrive not SyncDrive
Plus will work under DOS.
Q23. I am using a computer that is running
Card and Socket Services. Can I still get the DOS drivers for my
PCMCIA cards?
A. Yes. Quatech DOS drivers for Communication PCMCIA cards
can be found on the Support for Discontinued
Product page. These drivers are for use at your own risk, and
our technical support team cannot provide any help with installation,
configuration, or troubleshooting. However, our tip sheet "PCMCIA
for DOS" may provide some useful suggestions.
Q24. What does PCMCIA stand for?
A. Personal Computer Memory Card
International Association
This group is "an international standards body and trade association
with over 200 member companies that was founded in 1989 to establish
standards for Integrated Circuit cards and to promote interchangeability
among mobile computers where ruggedness, low power, and small size
were critical." (Excerpted from the pcmcia.org site). Its main job
is to oversee the continued development of portable peripherals
built on the PCMCIA form factor.
For more information on PCMCIA go to: www.pcmcia.org.
Q25. If I have problems not addressed in
this FAQ, what information do I need to submit on the technical
support request form in order to get help?
A. Please include the following information in the "description"
field of the technical support request
form:
- Product Model Number (ie: MPAP-200/300)
- Version of SyncDrive or SyncDrive Plus being used. (This can
be found on the Quatech COM CD)
- Type of C Compiler being used.
- Brief description of your application.(I.E. Bit-Sync, Byte-sync,
etc.)
- Specific explanation of the problem being experienced.
- Any error messages or error codes being generated
Q26. When installing a product, I get an error message stating "The System Cannot Find the File Specified." How can I fix this?
A. Windows 2000/XP has a bug that it cannot properly detect new hardware by *.inf files, if the RunOnce registry key is missing.
This key is often used by installers to execute post-reboot programs, but sometimes they accidentally delete this key.
Go to Start » Run and enter "regedit"
Go to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion
With CurrentVersion Highlighted, go to the Edit menu and select New » Key
Name the key RunOnce - Leave everything else about the key alone.
The RunOnce key should now exist underneath the CurrentVersion key.
Reboot your PC.
Once the key exists, Windows 2000/XP stops redetecting the Hardware
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