pcclock.doc

汇编大全 中国矿业大学计算机学院 汇编实验5

    standard addresses for COM1 and COM3, but none at 2F8h, the standard
    address for COM2, PCCLOCK (and DOS) refer to the port at 3E8h as COM2, not
    COM3.

2.  If your modem is connected to COM3 or COM4, the port is not at the standard
    address of 3E8h for COM3 or 2E8h for COM4, and your computer's BIOS
    recognizes only two ports, you will need to run a separate utility program
    to update the address of the port before PCCLOCK can use your modem.  One
    suitable utility is Port Finder, a shareware program that can be downloaded
    from CompuServe and many BBSs.  On CompuServe, Port Finder is currently
    available as PF253.ZIP in IBMCOM forum library 7.  Contact the author for
    assistance if required.

"Init" specifies the commands needed to initialize your modem.  "|" causes
PCCLOCK to send a carriage return character to the modem; "~" causes PCCLOCK to
delay one second before continuing to send commands to the modem.  The default
"Init" commands are accepted by most Hayes-compatible modems.  However, some

                                    Page 4
modems need to be initialized differently in order to communicate with the NIST
service, which was designed before modems with high speeds, error correction,
and data compression became widely available.  If you are unable to call NIST
using the default "Init" commands and have a 2400-bps modem, try setting "Init"
to "AT&FE1M1QV1|~~", where "&F" resets the modem to "factory default" settings.
If you have a 9600-bps (V.32) or 14400-bps (V.32bis) modem, or if your modem
supports error correction (V.42, MNP 1-4) or data compression (V.42bis, MNP 5),
try setting "Init" to "AT&FNS37=5\N%C|~", where "NS37=5" forces the modem to
operate at the 1200-bps speed of the NIST system, "\N"disables error
correction, and "%C" disables data compression.  If you are still unable to
call NIST, refer to your modem manual for information on communicating with
"older" modems.  Contact the author for assistance if required.

"Dial" specifies the modem commands needed to dial NIST.  As in the "Init"
parameter, "|" causes PCCLOCK to send a carriage return character to the modem.
The telephone number for the NIST atomic clock (1-303-494-4774) appears in this
parameter.  If you are calling from the 303 area code (northern and western
Colorado), you will need to delete the "303".  If you are calling from the
Boulder area, you may also need to delete the "1".  If you do not have tone
dialing (Touch Tone service), change "ATDT" to "ATDP" to use pulse dialing.
Under certain circumstances, such as calling outside a local telephone network
or using a special long distance service, you may need to use additional modem

+--------------+--------------------------------------------------------------+
| Command(s)   | Effect                                                       |
|==============+==============================================================|
| 0 to 9, #,   | Causes the modem to dial the specified digit.                |
| and *        |                                                              |
|--------------+--------------------------------------------------------------|
| space, (, ), | These characters are ignored by the modem, but may be used   |
| and -        | to increase readability of the command.  Example:  "ATDT 1   |
|              | [phone]|" has the same effect as "ATDT13034944774|".  |
|--------------+--------------------------------------------------------------|
| T            | Switches modem to tone dialing.  Use if you have Touch Tone  |
|              | service.  Example:  "ATDT1-303-494-4774|" (the default       |
|              | "Dial" command) calls NIST long distance using tone dialing. |
|--------------+--------------------------------------------------------------|
| P            | Switches modem to pulse dialing.  Use if you do not have     |
|              | Touch Tone service.  Example:  "ATDP1-494-4774|" calls NIST  |
|              | from within the 303 area code using pulse dialing.           |
|--------------+--------------------------------------------------------------|
| W            | Causes the modem to wait for another dialtone.  If no dial-  |
|              | tone is detected within a specified period (5 seconds for    |
|              | most modems), the modem hangs up and a "NO DIALTONE" result  |
|              | code is displayed.  Example:  "ATDT303-494-4774W33|" calls   |
|              | NIST using a long distance service that requires dialing the |
|              | called number, waiting for another dialtone, then dialing a  |
|              | special code.                                                |
|--------------+--------------------------------------------------------------|
| ,            | A comma causes the modem to wait for a specified period (2   |
|              | seconds for most modems) before continuing to dial.          |
|              | Example:  "ATDT9,494-4774|" calls NIST from the Boulder      |
|              | area, first dialing "9" then waiting briefly to dial outside |
|              | a local telephone network.                                   |
+--------------+--------------------------------------------------------------+

                       Table 2.  Modem Dialing Commands

                                    Page 5
commands.  Table 2 shows the modem commands that can be used between the "ATD"
and the "|" in the "Dial" parameter with most Hayes-compatible modems.  Some
modems have additional commands that can be used while dialing.  If you are
unable to dial NIST using the commands shown in the table, check your modem
documentation.

"Hang Up" specifies the commands needed to place your modem "on hook" when
valid data is received from NIST or when you cancel the call by pressing <Esc>.
"|" and "~" have the same effect as in the "Init" parameter.

"Time Zone" specifies an adjustment for your location to the "universal" time
(also known as UTC, GMT, or Zulu time) supplied by NIST.  Values for time zones
in the United States are predefined.  For time zones outside the United States,
select the value "Universal" and set the "UTC Offset" parameter.

"DST Observed" specifies whether or not Daylight Saving Time is observed in
your location.  PCCLOCK is able to automatically adjust the time supplied by
NIST for Daylight Saving Time only in U.S. time zones; therefore, this
parameter is not accessible when "Time Zone" is set to "Universal".

"UTC Offset" specifies an adjustment to the time supplied by NIST for locations
outside the U.S.  The value specified can be zero, positive, or negative.  This
parameter is accessible only when "Time Zone" is set to "Universal".

"Serial I/O" indicates which of two mechanisms PCCLOCK uses to communicate with
your modem, "Interrupt-driven" or "Polled".  See note below for details.


                                Important Note
                                --------------

  Some PCCLOCK users have reported that the interrupt-driven serial I/O
  mechanism, built into the programming language in which PCCLOCK is written,
  does not work properly with their modems.  Therefore, PCCLOCK includes an
  alternative polled serial I/O mechanism.  If interrupt-driven serial I/O
  does not work with your modem, please try polled serial I/O.  If neither
  works properly, please contact the author for assistance.


PCCLOCK.DAT
-----------

PCCLOCK uses the file PCCLOCK.DAT to save configuration parameters, any
modified clock designs, and settings for 12/24-hour mode, date/time display,
chime on/off, alarm time, and alarm on/off.

PCCLOCK.DAT will be created when PCCLOCK is first run and whenever it is not
found by PCCLOCK.  With DOS versions 3.0 and later, PCCLOCK.DAT is placed in
the same directory as PCCLOCK.EXE.  With earlier DOS versions, PCCLOCK.DAT is
placed in the root directory of the current drive.








                                 Page 6
Error Messages
--------------

The following messages may be displayed during modem timesetting operations:

  [Error:]  Date and time not set

  PCCLOCK did not set your PC's clock/calendar.  Possible causes:  The call to
  NIST could not be placed due to a "NO ANSWER" or "BUSY" status, a valid data
  string was not received within the 90-second timeout period, or the call was
  cancelled by pressing the <Esc> key.

  Invalid data received - Retrying . . .

  The preceding NIST data string was not in the correct format, and PCCLOCK is
  staying on-line until another data string is received.  Usually due to a
  noisy phone connection.

  Serial I/O error n

  PCCLOCK was unable to successfully communicate with your modem.  Possible
  causes:  PCCLOCK is configured for the wrong port, power to the modem was
  off, or the selected serial I/O mechanism is not compatible with your
  equipment.  Verify that your modem is operating correctly with your other
  software, and try both interrupt-driven and polled serial I/O (see
  "Configuration" above).  Contact the author for assistance if required.

The following messages may be displayed while printing a registration/order
form:

  Number of copies must be specified

  When registering, you must order at least one copy of the program on either
  a 5.25" or 3.5" diskette.

  Printer off-line or out of paper

  Self-explanatory.

The following messages may be displayed at the DOS command level:

  Error accessing <drive>:<path>\PCCLOCK.DAT - <reason>

  PCCLOCK was unable to read its configuration file upon start-up or write it
  upon exiting.  <reason> indicates the probable cause of the error.  Because
  PCCLOCK writes to PCCLOCK.DAT each time it exits, if PCCLOCK is run from
  diskette, the diskette should remain in the drive and should not be write-
  protected while PCCLOCK is running.

  Invalid video mode - PCCLOCK aborted

  The computer's display is not CGA, EGA, VGA, MCGA, XGA, or compatible, or was
  not set for 80-column by 25-line operation.





                                 Page 7
Revision History
----------------

+---------+------+------------------------------------------------------------+
| Date    | Ver. | Summary                                                    |
|=========+======+============================================================|
| 1/01/91 | 1.0  | Initial release.                                           |
|---------+------+------------------------------------------------------------|
| 2/05/91 | 2.0  | Added timesetting by modem.                                |
|---------+------+------------------------------------------------------------|
| 2/16/91 | 2.01 | Changed to ignore DSR and DCD signals to work with more    |
|         |      | modems.                                                    |
|---------+------+------------------------------------------------------------|
| 3/03/91 | 2.04 | Corrected problems with accessing COM3 and COM4.           |
|         |      | Improved validation of incoming data.                      |
|---------+------+------------------------------------------------------------|
| 4/07/91 | 2.10 | Added "AUTO" command-line option to call NIST and exit.    |
|         |      | Added functions to designate default clock design.         |
|         |      | Added functions to erase and restore clock designs.        |
|         |      | Eliminated need to press <Enter> to save modified clock    |
|         |      | designs.                                                   |