Data Bases • Custom Term Papers • Free Term Papers • Free Research Papers • Free Essays • Free Book Reports • Plagiarism? Links • Top 100 Term Paper Sites • Top 25 Essay Sites • Top 50 Essay Sites • Search 97,000 Papers @ DirectEssays.com • Search 101,000 Papers @ ExampleEssays.com • Search 90,000 Papers @ MegaEssays.com Free Essays • Term Paper Sites • Chuck III's Free Essays • Free College Essays • TermPaperSites.com • My Term Papers • Get Free Essays • Essay World • Planet Papers	Search Lots of Essays Back to Subjects - Technology Modem hardware Modem hardware First and foremost, my advice is that you should always have the most current drivers for your modem. These are most often available free of charge from your modem's manufacturer's web site. If you don't know the correct website for your modem manufacturer, check your documentation that came with your Factory Settings/Default Modem String If you cannot get your modem to initialize, try using AT&F1 or ATZ as your initialization strings. AT&F1 usually will return a modem to factory settings. ATZ should reset your modem to default settings. No Dial Tone and Modem Speaker Volume If you cannot get a dial tone, be sure that your modem is properly plugged in and connected to your system as well as the telephone jack. If applicable, make sure that your modem's speaker is turned up enough so that you can hear dial tones, busy signals, and handshakes. (Handshakes are the noises the modem usually makes as it is connecting with another modem). This will help you determine whether or not your modem is able to obtain a dial tone and even dial out. If it is able to get a dial tone and dial out, but cannot connect, it may be a problem with the modem you are trying to call. In Windows 95/98, you can change your modem speaker volume in the Control Panel, Modems. Select your modem, and click on "Properties" to raise or lower your modem's speaker volume. If you still cannot connect to the number, try using a different local access number. Try not to use a long telephone cord, as longer cables tend to have some signal degradation, which means slower connections and file transfers. Lots of people have asked how they can tell who made their no-name modem. Sometimes it's not important to know the exact manufacturer. The most common commands between modems are often the same. If you are using Windows 3.x, you probably don't need any specific modem driver. Lots of modems use a common chipset (such as Rockwell) on a board. Most of the time, you can find the chipset name printed on the largest chip on the modem, and sometimes you may find it by entering some of the AT "ID" commands (ATI1, ATI2, ATI3, etc.) in the screen of a communications program such as the Terminal and/or HyperTerminal programs. Terminal comes standard with Windows 3.x, and HyperTerminal is included with Win95/98. The ATI commands usually run up through 10 or 12, and you can learn a lot from them, such as the values in the s-registers, and sometimes even a list of modem commands. One of the ATI commands will usualy return some modem ID or chipset ID (Rockwell chipset ID's usually start with an "R"). If you know the chipset name, you can probably find drivers that you can download on the manufacturer's web site. To send AT commands to your modem(s), run the HyperTerminal program (HyperTrm.exe) which is usually found at Start, Programs, Accessories, HyperTerminal. In the "Connection Description" dialog box, enter the name "AT COMMANDS", choose any icon it offers, and click OK. On the "Connect Screen", do not enter a phone number, but rather click the down arrow on the "Connect Using" line and pick "Direct to Com#" (replace "Com#" with the communication port your modem is on). Save this session. From now on, just double click the "AT COMMANDS" icon to open a terminal screen within which you can communicate directly with your modem by AT commands. If you have a WinModem and cannot get it function in DOS or DOS Mode, it is due to the fact that WinModems will only function under Windows, and most do not use a Rockwell chipset. These modems will only function under Windows 3.x/Win95/98, although I have recieved information that suggests they might work under Windows NT as well, however that is currently beyond the scope of this file. If you cannot get your WinModem to function, I suggest checking your manufacturer's website and downloading the most current drivers for it. You may be able to access the Internet by using a friend, family, or co-worker's computer in order to obtain the drivers if you cannot connect to the Internet with your WinModem. You can then copy the drivers onto a floppy disk and use them in your own computer. Unplugging Devices From Modem's PHONE Jack This tip appears courtesy of thor@micronet.net (Ray) and AXCEL216@aol.com. If someone's modem is not connecting at its full potential the phone they have coming out of their machine may be effecting it. Most modems have a jack for "LINE" and "PHONE" the one labeled "LINE" being incoming and the one labled "PHONE" being outgoing. If there is a telephone or caller ID box connected to the "PHONE" (outgoing) jack, it may be affecting your Internet/Fax/BBS connections. For Ray, it would only connect at 31200 while the telephone was plugged into the "PHONE" (outgoing) jack, but when he unplugged the telephone from the "PHONE" (outgoing) jack he was connecting at 33600 every time. Thank you very much Ray and George for this tip. Ray (thor@micronet.net) and George (AXCEL216@aol.com) Some people have found that their Internet file transfers are quite slow, often between 900-1,800 characters per second, even on a 56k modem. It might very possibly be a result of a Windows 95/98 Maximum Transmission Unit (MTU) problem. Look at the "Bytes received/sec." in System Monitor (SYSMON) and compare it to the characters per second reported by your web browser. These two numbers should be within 10%-12%; so if your "Bytes received/sec." is 3,300, your characters per second should be around 3,000. If the characters per second are 900-1,800, you are getting a lot of unneeded retransmissions that are quite possibly due to the Windows 95/98 MTU problem. Microsoft has not released a fix for this yet, but if you download and run: "http://www.aimnet.com/~jnavas/modem/tcpipcfg.exe" (no quotes) and change your MTU value to 576 (the default is 1500), it will correct the MTU "bug" in Windows 95 versions 4.00.950 (retail), 4.00.950a (OSR1) and 4.00.950 B (OSR2), however, I have been unable to get TCPIPCFG.EXE to work when Microsoft Internet Explorer 4.0 or 4.01 for Win95, or Windows 98 (with IE 4.01 SP1) Update: [3/20/1998] A concerned reader (zrock@kermode.net) writes: I just read your modem tips file and you should clarify the MaxMTU fix. The setting 576 doesn't work for all ISP's it can range anywhere from 512 all the way to 1500.... 1500 is where my ISP's setting is set and where I get the best performance. I also noticed that just using MTUspeed to add the 1500 setting made a difference even though it is the Win95/98 default. I also noticed more of an improvement by installing Microsoft's Unimodem update (a huge difference) then rebooting, uninstalling my modem (rebooting), then reinstalling my modem drivers I jumped from 2.1 k/sec to over 3.0 k/sec. CptSiskoX@Geocities.com and zrock@kermode.net Unless you use ultra-high-speed serial boards or special buffers, an external serially connected ISDN modem will always result in slower performance than an internal ISDN modem. This is because the 16550 UART maximum is 115.2Kbps, not the 128Kbps a dual-channel ISDN connection is capable of reaching. If you want to get every drop of performance out of your ISDN modem, use an internal one. Any modem user has probably received an important transmission with characters missing. There is no way to find and retrieve the lost characters, but you can increase your odds of receiving data intact by adding a line or two to your SYSTEM.INI file. Before starting, it's important to understand how Windows handles incoming data transmissions. Your modem sends the data it receives to Windows' COMM driver. This stores the received data in a memory buffer until your communications program retrieves it. Unfortunately displaying and storing all the received data keeps your communications program working overtime. As a result, it can't always retrieve data from the COMM driver as often as it By default, Windows sets aside just enough buffer space to store 128 incoming characters. Unfortunately, once a modem has been connected, data flows continuously. Your computer can temporarily stop the flow of data, but doing that takes time. Meanwhile, data continues to arrive and must be stored in the COMM driver buffer. If your communication link is slow, or your communication program is fast, a 128-character buffer might suffice. But with a fast modem or a slow program, it's possible for more than 128 characters to arrive before your program can process them. In that case, the COMM driver has no place to store the 129th character and those that come after it. Luckily, you can expand Windows' COMM buffers. By adding a line to the [386enh] section of the SYSTEM.INI file, you can create a buffer as large as 10,000 characters. Actually since the COMM driver maintains a buffer for each of your PC's COM ports, you can add up to four lines, each controlling the size of a particular port's buffer. Each line should resemble this: Replace the x with a number between 1 and 4 to indicate the desired COM port, and substitute num with a number from 128 to 10,000 to set the buffer size. You have to exit and restart Windows for the change to take effect. Use a text As for how big should your COMM buffer be, if characters are being dropped from incoming data transmissions, create a new buffer of at least 2,048 (2KB) characters. If problems persist, increase the size of the buffer to Often, Win95/98 systems arrive with the COM ports set for 9,600bps, but if you're using a 14.4Kbps or faster modem, increase that. Open the Control Panel's System applet and click on the Device Manager tab. Expand the Ports entry, double-click on each serial COM port and follow these steps. Click on the Port Settings tab. Make sure your Bits Per Second entries read 115,200 or higher (or at least 57,600), and the Flow Control is set to Hardware. Next, click on the Advanced button and then select the "Use FIFO buffers [requires 16550 compatible UART]" option. You can experiment with the Receive and Transmit Buffer options in modem properties in Win95/98, but I suggest you just configure both to the highest setting and bring them down if communication problems arise. If Windows 95/98 didn't recognize and install your modem correctly, it may not be using the right AT initialization string for a dial-up connection which could hamper performance. To check this setting, open the Modems applet in the Control Panel. The modem brand and type should match the one installed on your system. If it doesn't match, highlight it and click on the Remove button in the Modems Control Panel; then click on the Add button and follow the wizard Faster Data Transfer and Connection Speeds For Win95/98, in the Modems Control Panel, click on the Properties button. Under the General tab, make sure the "Maximum Speed" is configured to 115,200 or higher (or at least 57,600). Open the Connection tab, click on the Advanced button and check the User Error Control, Compress Data and Use Flow Control Line noise is one of the easiest things to detect. This is almost never a problem on ISDN, DSL, or cable modems. But on a regular analog telephone line, this can have a major impact. One rather crude method of testing for line noise is to pick up the telephone receiver (while not connected by your modem on the line) and listen for static-like, crackling sounds. These are often indications of line noise. It can be caused by faulty wiring, moisture, and several other factors. The best way of getting rid of it is to use as short of phone cords as possible with your modem, and if problems still persist, call your telephone provider and have a technician come to your home and analyze your line quality. Don't let them leave until it is *crystal* clear to the point where you can hear a pin drop. If you are experiencing random dropped connections, try turning off data compression. Also making sure that error correction is on and flow control is set for Hardware (RTS/CTS) usually helps. Data compression set "on" is a default configuration in most modems. When Win95/98 detects a modem, it tries to load an initialization (.inf) file for that modem brand and model. If Win95/98 isn't sure what modem is installed, it loads a default file named modem.inf. With modem.inf being used, Windows may or may not send the correct command to disable data compression. If this happens, read your modem documentation and enter the AT command to disable data compression. Click Start, Settings, Modems, Properties, Connection, Advanced, and then type the AT command(s) in the Extra Settings box. Modems have limited buffer space for both error correction and data compression. Error correction is necessary to provide an error-free connection. Also, when errors do happen, modem buffer space is needed to correct them. Modems have error thresholds that, when exceeded, will cause serial overruns and will hang up the call, resulting in a disconnection. Sometimes modems will "lock" into a mode and won't respond to any initialization or "AT" commands. Often times, powering down the PC and turning it back on a few moments later will reset the modem to its default state and it will again accept your commands. It may only be necessary to exit Windows if you are using Win 3.x or if you are using Windows 95/98/NT then restarting the PC by using the "Start, Shut Down, Restart the Computer" option, which is a little faster than having to completely power off the PC. Rather than wasting time with a completely non-responsive modem (assuming it had been working prior to its non-responsiveness) this will often fix the Has a modem company mistreated you as a customer or not come through on a promise they advertised on the box your modem came in? Were you promised free upgrades only to find it's a hassle to get them to deliver on it/them? Then you aren't alone. If this has happened to you, then you can visit The Better Business Bureau at www.bbb.org an submit a complaint, stating what had happened and providing all relevant information. This isn't by any means limited to modems, but in this case it was. If any company, computer-related or otherwise tries not to deliver on their promises, I would definitely say this is a course of action you have open to you. The page you will need to visit to actually complete the complaint is: http://www.bbb.org/complaints/consumerform.html Do *NOT* mention me in your complaint please as I have NOTHING to do with your individual complaints. I am NOT affiliated with The Better Business Bureau in any way and do not wish to associate myself with them, but they may be able to help you if you've been mistreated by a company. If the "Log on to network" option is selected, Dial-Up Networking tries to find a Microsoft Windows Network. If it doesn't find one, the connection will time out. To disable the "Log on to Network" option, follow these steps. Click Start, Programs, Accessories, Dial-Up Networking. Right click the connection you use to connect to your Internet Provider. Click Properties. On the Server Types Tab, clear the check box for the "Log on to Network" This tip is to ensure that you are using the right protocols when connection to your ISP. Windows 98 by default installs NetBEUI, IPX/SPX, and TCP/IP protocols to the dial-up adapter, but most ISPs only require TCP/IP to connect To disable unnessary protocols in the connection, click on Start, Programs, Accessories, Dial-Up Networking, right click the connection for your ISP and click Properties. On the Server Types tab, under "Allowed Network Protocols" clear the NetBEUI and IPX/SPX checks. To make sure that you have the right protocols, in this case, TCP/IP, click Start, Settings, Control Panel, Warning About 3COM/US Robotics Modems Many people have been writing and reporting complaints with US Robotics/3COM modems under Microsoft Windows 95 and Microsoft Windows 98. Windows 95/98 seem to have trouble detecting and/or installing the proper drivers for these types of modems, especially newer ones. If this happens to you, try installing the driver from the US Robotics/3COM CD-ROM that came with the modem or download the newest drivers from their website by using another computer with a functioning modem, then copying them to the machine having problems by using a floppy disk. Point the setup program to the correct drivers and select your modem from the list. This should get Windows 95/98 to recognize your modem Avoid Disconnections Using Most Modems Try putting this in your "Extra Settings" box in Win95/98's Modem Control Panel applet if you suffer from random disconnections. It has been known to help improve reliability substantially on many modems. Here is the INIT to try: "ATS15=128 &K3 S34=32 S12=0" (no quotes). This is best for use with US Robotics and 3COM modems but should work with Sometimes modems will experience interference in their connections and data transmissions. Often, this can be attributed to having other lines touching the telephone cord that connects your modem to the telephone jack. Being in contact with cable TV, printer, monitor, and even joystick cords or cables can cause data corruption and interference in some cases. If you are experiencing these kind of unexplained problems but seem to have no line noise on your line, this could be a possible reason why it is happening. To get rid of this problem, make sure that your telephone cord isn't touching any other cords or cables, and then try your connection again. Hopefully, you'll have better If you want to increase the port speed to your modem under Windows NT 4.0, you may have tried to find the "Device Manager" in the Control Panel by opening the "System" applet. Windows NT 4.0 keeps it's port settings in the Control Panel in the "Ports" applet. Simply open it and select the port(s) you wish to adjust, then make the desired changes and close it. You may be prompted to reboot. Upon rebooting, your new port settings will have taken effect. Bibliography: Word Count: 3213
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