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───────────────────────────────────────────────────────────────────────
*** VBBS MODEM DOCUMENTATION ***
───────────────────────────────────────────────────────────────────────
VBBS comes preconfigured to work correctly with MOST modems.
If you are configuring for a 2400 baud modem in particular, it is
likely that the extent of your modem setup will be limited to chosing
the correct modem port in VCONFIG's channel.cfg.
Some modems, particularly some of the newer manufacture high
speed modems may require a bit more configuration and for that reason,
exclusive setup and initialization information is provided in this
document for many of the more popular high speed modems.
------------------
High Speed Modems:
------------------
Recent developments in the high speed modem market has found
the price of high speed modems dropping substantially over the past
several months. This is due primarily to a particular communications
chipset designed and manufactured by the Rockwell corporation. These
modems are "V.32bis" (14.4k baud) modems and most as well contain a FAX
facility as well. The price of these modems are currently ranging from $199
which is SUBSTANTIALY less expensive than high speed modems of lesser
speeds were priced only 1 year ago.
Many modem manufacturers offer SysOps of BBSs a special
discount off the User retail price of their modems. Information on current
SysOp deals on modems as well as extended help on setting up all
modems with VBBS can be found on the VirtualNET modem message base.
--------------------------------------------------------------------------
Additional Modem Set-Up assistance is available from any VBBS Support BBS.
--------------------------------------------------------------------------
VBBS and the Modem Initialization Setup
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
----------------------------------
The VCONFIG/Channel Configuration:
----------------------------------
VBBS presently allows up to 64 phone lines to be configured, even though in
most cases only the first 1 or 2 channels will be used by the average hobby
sysop. Explainations will lean more towards this, for it is sufficient
enough if you were to connect more lines.
For each Data line in VBBS, a channel (phone line) configuration must be
set to define the Serial Com port that the individual line(s) will be
running from. Below is a example layout.
1.) Com Port :
2.) Base Address (Hex):
3.) IRQ (Hex) :
4.) Baud Rate :
5.) Init String :
6.) Locked Baud Rate :
7.) Hardware (RTS/CTS) Handshake :
8.) Minimum Baud allowed :
1.) Com Port:
--------------
Define Commmunications port 1-8 per channel. If by chance you use more
than eight different channels in the board, it is possible to use a Com
Port more than once, but MUST be addressed differently in the Base Address
field to prevent an IRQ conflict. (See Section on IRQ's).
2.) Base Address:
------------------
This is were you define the Base address that DOS understands as the Port
assignment for the channel. (example: COM1 is 3F8, COM2 is 2F8).
3.) IRQ:
---------
Assignment for IRQ (Interupt Requests) that must be set for further
definition of the Com port channel. (See Section on IRQ's for more
technical reference).
4.) Baud Rate:
---------------
Define your Modem's baud rate speed, from 300 to 57600.
Note: 300/1200 and 2400 baud modems must be set for thier Proper speed.
High Speed modems use the Locked Baud Rate that your High speed can handle,
for instance, if you have a 14.4 modem, you would define 14400, 19200,
38400 or 57600, whatever your modem allows, and also whatever works
accordingly to the type of computer equipment it is handling.
5.) Init String:
----------------
This is the Modem initialization string used by VBBS for the particular
channel to define the reset and operation of the channel with your Modem.
(see section on Modem NRAM's and INIT Strings for further definition).
6.) Locked Baud Rate:
---------------------
Toggle Yes/No for Locked Baud Rate on High Speeds. This should be set to
no for 2400's and below.
7.) Hardware (RTS/CTS) Handshake:
----------------------------------
Three Options can be toggled for this, and is only used for High Speed
modems. No, Yes(Normal), and Yes(Slow). Most likely, you will want to set
this for Yes(Normal), because it behaves the best for High Speeds and error
control.
8.) Minimum baud rate allowed:
-------------------------------
This option is new to 5.50 and allows the sysop to configure what the
minimum speed for the channel/modem shall be. This choice is beneficial to
sysops not wanting 300 or 1200 baud callers, or the sysop may set it for a
minimum baud of 9600 for a particular Channel if they just want thier High
Speed Modem Line available only to High Speed callers.
Serial Cards and Com Ports:
UART Chips and Recommendations:
What is the 16550 and how can it benefit communications?
--------------------------------------------------------
The chip, formally known as the NS16550AFN chip, is the heart of your
asynch board. It is the UART chip, or Universal Asynchronous Receiver/
Transmitter.
The advantage of the 16550 over the older 16450 and 8250 UARTs is that
it has a 16 byte buffer on it. Now, sixteen bytes doesn't sound like a
whole heck of a lot but it is SIXTEEN TIMES the size of the buffer on
the older UARTs which only had one a one byte buffer.
The advantages of the 16-byte buffer are two fold:
1) It makes high speed communications more reliable.
On the older chips, with their one-byte-buffer, you would lose data
if a second byte came in from the modem before the CPU had a chance
to pull the first byte out. The 16550, with its 16-byte-buffer,
gives the CPU up to 16 chances to pull the data out before a
character is lost.
To realize what this means you can figure that at 19200 bps you are
expecting the CPU to service the comm port 1920 times each second or
once every .0005 seconds. If the CPU happens to take .0006 seconds
to get around to servicing the comm port then in a one-byte buffer
UART that first byte is lost. On the 16550 chip, with 16 bytes of
buffer space, you have up to .008 seconds to service the comm port.
2) It helps make a multitasking system more efficient.
When VBBS is transmitting data it has to stop the CPU and fill the
UART's transmitter buffer. That means that if the caller in the
background is doing a directory scan his scan will take longer while
VBBS attempts to send data out to the first caller.
In the one-byte-buffer UARTs at 19200 bps VBBS must stop the CPU
1920 times each second just to send data out the comm port. With
the 16550, however, it can stuff up to 16 bytes into the buffer at
a time and therefore interrupts the CPU only 120 times each second.
That drops the performance hit on the CPU, even at high speeds, to
almost that of a 1200 to 2400 bps modem!
To top it off... the older 8250 chips were buggy, making them less
reliable, and they were never designed for the high speeds that we
expect out of our modems today. The NS16550AFN, on the other hand, is
designed with high bus speeds and high modem speeds in mind. When
multitasking, even at slower baud rates, the 16550 can be very helpful
in providing smooth operation for the entire system.
--------------------------------------------------------------------------
Modem Initialization Settings:
Modem Setups and Init Strings:
For all practical purposes 300/1200/2400 Baud modems are probably the
easiest to setup and run, because they have no internal VCHIPS in them like
v.32, v42, etc. and for VBBS should require only a workable Init String to
maintain operation. Below are Init strings gathered over time from sysops
on the VirtualNET, and should function well depending on the brand that you
have.
Modem AT command settings
--------------------------------------------------------------------------
Standard 2400 bps or 1200 bps Hayes Compatibles (NON-MNP):
If your modem supports the extended "&" command set, then try:
ATX4Q0E0V1&C1&D2S2=251S7=40
X4 Enables extended result codes
Q0 Modem returns Result Codes
E0 Modem does not echo commands back to the computer
V1 Modem returns Verbal Result Codes
&C1 Modem asserts Carrier Detect based on connection status
&D2 On DTR high-to-low transition, Modem Hangs Up.
S2=251 Disable Modem Escape Sequence
S7=40 Time Modem waits for a carrier when initiating a new connection
If your modem does not support the & command set, try using:
ATX4Q0E0V1S2=251S7=40
Modems which do not use the & command set usually have DIP switches of some type
to set their mode of operation. Verify that your modem is set to:
a) Assert CD (carrier detect) only when conencted to a remote modem
b) Hang Up on drop of DTR (data terminal ready)
--------------------------------------------------------------------------
Exclusive High Speed Modem NRAM Setups.
Below is a collection of workable NRAM Setups, some with INIT strings that
have proven usable with VBBS for Channel assignments.
--------------------------------------------------------------------------
US Robotics Courier HST / Courier Dual Standard:
Since the HST utilizes so many settings, it is almost impossible to include
them all in one initialization string. Therefore, you may wish to use the
NRAM feature to store the settings which are common to most applications,
and use the VBBS init string for VBBS-specific settings.
NRAM Settings Recommended:
X7 Return full result codes
&H1 Turns on hardware handshaking for output from DTE (CTS line) *
&R2 Turns on hardware handshaking for input to DTE (RTS line) *
&B1 Fixes the DTE to DCE rate **
&N0 Negotiates highest link rate with fallback/fallforward enabled
&M4 Enables ARQ if remote modem has ARQ
&C1 Modem asserts carrier detect based on connection status
&D2 On DTR high-to-low transition, modem hangs up
&A3 Give FULL EXTENDED Result Codes
(choose one of these 3 &K commands based on your preference)
&K1 Enables data compression if remote modem requests compression
&K3 Enables V.42 bis data compression but not MNP5
&K0 Disables all compression
ATI4
USRobotics Courier 14400 HST Dual Standard Settings...
B0 C1 E1 F1 M1 Q0 V1 X7
BAUD=38400 PARITY=N WORDLEN=8
DIAL=HUNT ON HOOK TIMER
&A3 &B1 &C1 &D2 &G0 &H1 &I0 &K3 &L0
&M4 &N0 &P0 &R2 &S0 &T5 &X0 &Y1 %R0
S00=000 S01=000 S02=251 S03=013 S04=010
S05=008 S06=002 S07=045 S08=002 S09=006
S10=007 S11=050 S12=050 S13=000 S14=000
S15=008 S16=000 S17=000 S18=000 S19=000
S20=000 S21=010 S22=017 S23=019 S24=150
S25=000 S26=000 S27=000 S28=008 S29=020
S30=000 S31=000 S32=001 S33=000 S34=000
S35=000 S36=000 S37=000 S38=000
- Or use this -
ATI4
USRobotics Courier 14400 HST Dual Standard Settings...
B0 C1 E1 F1 M1 Q0 V1 X7
BAUD=19200 PARITY=N WORDLEN=8
DIAL=HUNT ON HOOK TIMER
&A3 &B0 &C1 &D2 &G0 &H1 &I0 &K3 &L0
&M4 &N0 &P0 &R2 &S0 &T5 &X0 &Y1 %R0
S00=000 S01=000 S02=251 S03=013 S04=010
S05=008 S06=002 S07=045 S08=002 S09=006
S10=007 S11=070 S12=050 S13=000 S14=001
S15=008 S16=000 S17=000 S18=000 S19=000
S20=000 S21=010 S22=017 S23=019 S24=150
S25=000 S26=000 S27=000 S28=008 S29=020
S30=000 S31=000 S32=001 S33=000 S34=000
S35=000 S36=000 S37=000 S38=000
and for your VBBS initialization string, use:
ATX7Q0E0V1S2=251S7=25&H1&R2&B1&M4&N0&K1&A3
- or, at least -
ATX7Q0E0V1S2=251S7=25&H1&R2&B1&A3
--------------------------------------------------------------------------
USR 9600 HST:
Use the init string above, stated for the USR/DS.
USRobotics Courier 9600 HST Settings....
C=1 E=1 F=1 M=3 Q=0 V=1 X=7 B=1
BAUD=19200 PARITY=N WORDLEN=8
DIAL=TONE ON HOOK TIMER
&A1 &B1 &G0 &H1 &I2 &K0
&M4 &N0 &P0 &R2 &S1 &Y1
S00=000 S01=000 S02=251 S03=013
S04=010 S05=008 S06=002 S07=025
S08=002 S09=006 S10=007 S11=040
S12=050 S13=000 S14=001 S15=000
S16=000 S17=000 S18=000 S19=005
S20=000 S21=010 S22=017 S23=019
NVRAM Settings
USRobotics Courier 9600 HST NRAM Settings....
DIAL=TONE M=3 X=7 F=1 B=1
BAUD=19200 PARITY=N WORDLEN=8
&A1 &B1 &G0 &H1 &I2 &K0
&M4 &N0 &P0 &R2 &S1 &Y1
S02=251 S03=013 S04=010 S05=008
S06=002 S07=025 S08=002 S09=006
S10=007 S11=040 S12=050 S13=000
S15=000 S19=005 S21=010 S22=017
S23=019
--------------------------------------------------------------------------
Compucom High Speed Modems:
AT&F2*H1%C0\N0S25=2M0QV1ES11=50&C1&D2H&W
Compucom STAR:
AT&F2*H2&D2S7=75&Y0&WX4M0L0S11=50
This may be too long to fit in the init string space provided by VBBS,
If so, just assign all these values to one of the NRAM settings, and init
string will actually read:
ATZ0
To assign an NRAM setting (2 are available, 0 and 1) type in the init string
above, in whole or in parts, and then type:
AT&W0
To disable the CCSP (Compucoms proprietary protocol) type
AT*H0
Baud rate should be locked and set to 19200, or 38400 for those with 16550
UARTs.
--------------------------------------------------------------------------
TwinCom V.32:
(No NRAM settings submitted)
ATE0H0M0Q0V1X4S0=0S2=1W0S95=145
--------------------------------------------------------------------------
Cardinal 9600:
(No NRAM settings submitted)
ATW2Q0V1E0&D2&C1S2=251M0&W2S95=1235
- or -
ATQ0V1E0&D2&C1S2=251S7=45M0
--------------------------------------------------------------------------
Supra/Fax 14.4:
NRAM settings can be run as default factory....
AT&F2 and then AT&W to write the set.
AT&K3\N3\T5E0H0M0Q0V1X4S0=0S2=1W2S95=3
--------------------------------------------------------------------------
Lightning Communications:
AT&FE0&D2&C1&Q9S7=65W2M0
Locked Baud Rate: 38400
RTS/CTS : Slow
(No Current Information provided on NRAM)
--------------------------------------------------------------------------
Zoom 14400 Fax/Modem:
Locked Baud Rate: 38400
RTS/CTS : Slow
AT&C1&D2E0H0Q0V1X4W0S95=3\T2
--------------------------------------------------------------------------
Zoom 2400 V.42bis:
ATX4Q0V1E0&D2&C1S2=251S7=45
ACTIVE PROFILE:
B1 E1 L2 M1 N1 P Q0 V1 W1 X4 Y0 &C0 &D0 &G0 &J0 &K3 &Q5 &R0 &S0 &T4 &X0 &Y0
S00:000 S01:000 S02:043 S03:013 S04:010 S05:008 S06:002 S07:045 S08:002 S09:006
S10:014 S11:095 S12:050 S18:000 S25:005 S26:001 S36:005 S37:000 S38:020 S44:003
S46:138 S48:000 S49:008 S50:255
STORED PROFILE 0:
B1 E1 L2 M1 N1 P Q0 V1 W0 X4 Y0 &C0 &D0 &G0 &J0 &K3 &Q5 &R0 &S0 &T4 &X0
S00:000 S02:043 S06:002 S07:030 S08:002 S09:006 S10:014 S11:095 S12:050 S18:000
S25:005 S26:001 S36:005 S37:000 S38:020 S44:003 S46:138 S48:007 S49:008 S50:255
STORED PROFILE 1:
B1 E1 L2 M1 N1 P Q0 V1 W0 X4 Y0 &C0 &D0 &G0 &J0 &K3 &Q5 &R0 &S0 &T4 &X0
S00:000 S02:043 S06:002 S07:030 S08:002 S09:006 S10:014 S11:095 S12:050 S18:000
S25:005 S26:001 S36:005 S37:000 S38:020 S44:003 S46:138 S48:007 S49:008 S50:255
--------------------------------------------------------------------------
ZyXel High Speed:
this is saved as Profile 0. Init string is just ATZ0.
Be aware that register S20 sets the DTE speed, set to 19200, so you
may want to change this to S20=2 or S20=1.
Current Setting.............
B0 E0 L4 M0 N5 Q0 V1 X6
&B1 &C1 &D2 &G0 &H3 &J0 &K4 &L0 &M0 &N0 &P0 &R1 &S0 &X0 &Y0
*B0 *C0 *D0 *E0 *I0 *M0 *P9 *Q2 *S0
S00=000 S01=000 S02=251 S03=013 S04=010
S05=008 S06=003 S07=060 S08=002 S09=006
S10=007 S11=070 S12=000 S13=000 S14=002
S15=002 S16=000 S17=018 S18=000 S19=000
S20=003 S21=176 S22=000 S23=112 S24=133
S25=000 S26=000 S27=156 S28=064 S29=000
S30=000 S31=017 S32=019 S33=000 S34=030
S35=000 S36=000 S37=000 S38=016 S39=000
ZyXEL 14400 V.32 V.32bis V.42 V.42bis Send/Recieve Fax/Modem:
AT&FX6E0&C1&D2&G2H0M0|
Locked Baud: 19200
harware handshaking normal
---------------------------------------------------------------------------
DESCRIPTION OF COMMUNICATION STANDARDS. INCLUDES MODEM & FAX.
---------------------------------------------------------------------------
STANDARD NAME DESCRIPTION
---------------------------------------------------------------------------
CCITT v.21 Standard for 300 bps. (FSK).
Bell 103J
Bell 202 Old standard for 1200 bps, half duplex. Leased lines.
CCITT v.22 Standard for 1200 bps. (DPSK).
Bell 212A
CCITT v.22bis Standard for 2400 bps. (DPSK).
CCITT v.26ter Standard for 2400 bps with echo cancellation.
Bell 208 Standard for 4800 bps. Used on leased lines.
CCITT v.27ter Standard for G3 FAX at 4800 bps with fall back to 2400 bps.
CCITT v.29 Standard for G3 FAX at 9600 bps with fall back to 7200 and
4800 bps. Also v.27ter/v.29 is used by CompuCom modems.
Half duplex. Reverse direction bps (slow?).
CCITT v.32 Standard for 9600 bps with echo cancellation. Fall back
to 4800 bps. Both direction simultaneously. (QAM).
CCITT v.32bis Standard for 14400 bps with echo cancellation. Fall back
to 12000, 9600, and 7200 bps. (TCM). Both directions
simultaneously.
CCITT v.33 14400 with fall back to 12000 bps. Used for what?
USR HST14400 US Robotics HST modulation. 14400 bps in one direction
and 450 bps in reverse direction. Fall back to 12000,
9600, and 4800 bps.
Trailblazer Proprietary and fast! Up to 18000 bps. ???
Hays V-Series Proprietary full-duplex 9600 baud. Hays its own CCITT LAP-B
error correction and its own scheme for data compression.
EIA Class2 FAX Fax standard called G2. ???
CCITT v.FAST Standard for 19200 bps or slightly higher. Uses echo
CCITT v.32bisbis canellation and is not FINALIZED. The first modems will be
available in late 1993. The name of the standard has not
been determined yet. It will have a much greater capability
to adapt modem speeds to meet existing conditions (more than
any existing modem). Theory sets a limit in the low 20000
bps range. This will probably be the LAST analog modem
standard.
ISDN Integrated Services Digital Network. This uses fiber optic
cable. It is currently available in larger cities within
3 miles (has been lengthen) of the central office. Available
in two flavors: Primary Rate Interface service and Basic
Rate Interface service. Basic, also known as 2B+D provides
users with two 64Kbit/sec channels for voice and data and
one 16Kbit/sec channel used by the carrier for call setup
and network management. The primary, also known as 23B+D
provides 23 64Kbit/sec channels and one 16Kbit/sec channel.
Some recent west coast subscribers will be paying a one
time $75 fee for a network connection device and $97 per
month for service, which includes two voice lines.
SMDS Switched Multi-Megabit Data Service. Uses fiber optics.
???
HDSL High-rate Digital Subscriber Link. Bell Labs and Bellcore
have recently developed this technology. It is capable of
carrying 1.5 megabits/sec over copper phone lines! Limited
to about 3 miles from the central office. Benificial since
it provides high speed data rate without running new fiber
optic cable to the customer. This is still in the labs.
---------------------------------------------------------------------------
MODE BPS BAUD MODULATION NOTES
---------------------------------------------------------------------------
v.33 14400 2400 128-TCM
v.33 12000 2400 64-TCM
v.32bisbis 19200 2400 512-TCM TBD ???
v.32bis 14400 2400 128-TCM
v.32bis 12000 2400 64-TCM
v.32bis 9600 2400 32-TCM
v.32bis 7200 2400 16-TCM
v.32 9600 2400 32-TCM
v.32 9600 2400 16-QAM Uncoded
v.32 4800 2400 4-DPSK
v.29 9600 2400 16-QAM
v.29 7200 2400 8-QAM
v.29 4800 2400 4-DPSK
v.27ter 4800 1600 8-PSK
v.27ter 2400 1200 4-DPSK
G3 FAX -> -> -> According to v.29/v.27ter
v.22bis 2400 600 16-QAM
v.22 1200 600 4-DPSK Same as BELL 212A
ISDN 65536 65536 FiberOptic Digital
The baud rate over the phone line means that more than two tones are used at
the baud frequency to achieve the bps rate. 4-DPSK means four tones...
---------------------------------------------------------------------------
NAME DESCRIPTION OF ERROR CORRECTION AND DATA COMPRESSION
---------------------------------------------------------------------------
MNP1 Hardware error correction.
MNP2 Hardware error correction.
MNP3 Hardware error correction. Strips off start and stop bits during
transmission over phone line.
MNP4 Hardware error correction. Fastest way to send compressed files.
Strips off start and stop bits during transmission. Also adapts
to line conditions.
MNP5 Hardware error correction and data compression (up to 2 time
compression on TEXT). Do NOT use on compressed files!
MNP6 Additional Universal Link Negotiation and Statistical Duplexing
to MNP5 service
MNP7 Additional Enhanced Data Compression with MNP4.
MNP8 Nothing available ???
MNP9 Additional Enhanced Data Compression with v.32 modems Also adds
Enhanced Universal Link Negotiation, which allows connection to
both MNP and non-MNP modems at the highest performance level.
MNP10 Hardware error correction and data compression. Special!
v.42 CCITT error correction. LAPM. Fastest way to send compressed
files. Strips off start and stop bits during transmission.
v.42bis CCITT data compression (up to 4 time compression on TEXT).
Uses a version of the Lempel-Ziv data compression algorithm.
---------------------------------------------------------------------------
baud means Actual rate of symbols trasmitted per second.
bps means Bits Per Second.
MNP means Microcom Networking Protocol.
CCITT means International Telephone and Telegraph Consultative Committee.
FSK means Frequency Shift Keying.
DPSK means Phase Shift Keying.
QAM means Quadrature Amplitude Modulation. Combination of PSK and AM.
TCM means Trellis Coded Modulation.
LAPM means Link Access Procedure for Modems.
--------------------------------------------------------------------------