Software Vault: The Diamond Collection

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Computer Help References version 1.19.95 ──────────────────────────────────────────────────────────────────────────── H A R D W A R E ──────────────────────────────────────────────────────────────────────────── As new information is added, it will appear at the beginning of each specific section. All new information will have the date it was added in the header. If you find something you've read before that is marked as a new addition, it is due to a correction, or addition to that topic. ──────────────────────────────────────────────────────────────────────────── Testing for a Defective Pentium (586) Chip ========================================== -> Added on January 19, 1994 Here is a test that will uncover the Pentium bug if you have it. This test was used in Excell spreadsheet but others should give the same results! Pentium 486 ─────────────────────────────────────────────────────────── 1. Take this number 4195835 4195835 2. Multiplied by 3145727 3145727 3. Divide by 3145727 3145727 ─────────────────────────────────────────────────────────── 4. Your answer 4195579 4195835 Good Luck with the test! * David Coller @ 1:234/40 ──────────────────────────────────────────────────────────────────────────── 3 Different types of "slots" ============================ -> Added on January 19, 1994 VL-Bus connectors have _three_ in-line expansion slots. Just like the 16bit ISA (AT) bus added an extension to the end of the PC's 8bit slot, the VL-Bus slot adds yet another, like this: ---Three--- -----Four------ -One-- -VLB slots- ---ISA slots--- -8bit- ┌─────────────────────────────────────┐ │ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ │ \ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ \ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ 8bit portion │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ of the bus │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ / │ └─┘ └─┘ └─┘ └─┘ └─┘ └─┘ └─┘ └─┘ │ / │ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ │ \ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ 16bit portion │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ of the bus │ └─┘ └─┘ └─┘ └─┘ └─┘ └─┘ └─┘ │ / │ ┌─┐ ┌─┐ ┌─┐ │ \ │ │ │ │ │ │ │ │ \ │ │ │ │ │ │ │ ┌─────┐ │ 32bit portion │ │ │ │ │ │ │ │ 486 │ │ of the bus │ │ │ │ │ │ │ │ CPU │ │ / │ └─┘ └─┘ └─┘ └─────┘ VLB motherboard │ / └─────────────────────────────────────┘ * Vernon.Frazee@f71.n135.z1.fidonet.org ──────────────────────────────────────────────────────────────────────────── 3 Ways to Control a Hard Drive ============================== -> Added on January 3, 1994 I have just gotten some new experience with 32bda and BIOSes ... A friend of mine has a new Pentium, and he wasn't able to get Windows 32 bit DISK access (32bda) working on his system. I looked into his IDE setup in BIOS and found that he was using the new EIDE drive access methods. Standard IDE is accessed with what is known as standard CHS (Cylinder/Head/ Sector), but EIDE has two other methods over those: Extended CHS, and LBA (Logical Block Access). Both ECHS and LBA are methods for accessing IDE hard drives larger than 528MB. LBA is the most sophisticated protocol, and ECHS is an intermediate protocol between LBA and the old CHS. His BIOS setup autodetects which method is suitable to use with his drives, and chooses appropriately. It first checks for LBA, then ECHS, and finally standard CHS. Often the smaller IDE drives won't work with LBA at all, so the next method they try is ECHS. There is almost no difference between CHS and ECHS as far as the drives are concerned, and the autodetect usually settles on ECHS. This is where the problem arises: the BIOS is using ECHS, while the 32bda of Windows (which is a replacement for BIOS while running Windows) emulates only CHS. The standard 32bda polls the BIOS for information regarding the drive physical characteristics, and finds that it doesn't really understand the format, because the information is in ECHS format not CHS format. I was able to solve his problem by simply going into the BIOS setup and manually overriding the autodetected method with a standard CHS method. There is no need to use LBA or ECHS unless you have drives that are bigger than 528MB, so you might as well use standard CHS. There are no performance benefits to using the newer access protocols either over standard CHS, they are just there to allow access to drives greater than 528MB, so you might as well use standard CHS. * Yousuf Khan @ 1:163/525 or 1:163/215 ──────────────────────────────────────────────────────────────────────────── Bigger Hardrive Means Bigger Appetite ===================================== -> Added on January 3, 1994 Did you just buy and install a BIG hard disk? You probably took the easy route and partitioned it as one whole physical drive, right? Did you know that a large partition on a hard disk is one of the biggest waste of hard disk space? Here is a simple chart of space used by each cluster in relation to the actual size of the Hard Drive itself. Size of Partition in MB Size of Cluster in Kbytes 16 - 127.99 2 128 - 255.99 4 256 - 511.99 8 512 - 1023.99 16 1024 and greater ?? Where the waste comes in are those files that are smaller that the size of each individual cluster. Have you ever considered how many files you have that are that small? As the MB partitioning increase, the amount of wasted disk space increases because those small files are going to consume the next largest cluster size. As an example ... the majority of CONFIG.SYS and AUTOEXEC.BAT files are probably under 1K. If these two files were on a partitioned drive of 420MB, those two files would consume 16K of disk space even though together they are less than 2K in size. I guess the answer to the question is the effort worth it?!? Breaking down your large hard drive after it's in use could involve fooling with several drives to move between during each operation; starting the backup programs again and again when the tape has finished with one drive and trying to keep track of the tapes; or worse yet using a "million" floppies. And having compressed drives can only complicate the situation. The choice is yours! * Bill Gaston @ 1:382/91 ──────────────────────────────────────────────────────────────────────────── P.O.S.T. Screen Error Messages ============================== -> Added on December 7, 1994 01x Undetermined problem errors; 02x Power supply errors; 1xx System board errors; 101 Interrupt failure 102 Timer failure 103 Timer interrupt failure 104 Protected mode failure 105 Last 8042 command not accepted 106 Converting logic test 107 Hot non-maskable interupt test 108 Timer bus test 109 Memory select error 110 PS/2 parity check error 111 PS/2 memory adapter error 112 PS/2 MicroChannel arbitration error 113 PS/2 MicroChannel arbitration error 121 Unexpected hardware interrupts occured 131 PC system board cassette port wrap test failure 161 System options not set (run SETUP) - dead battery 162 System options not set (run SETUP) - CMOS checksum/config. error 163 Time and date not set (run SETUP) - clock not updating 164 Memory size error (run SETUP) - CMOS setting does not match memory 165 PS/2 system options not set 166 PS/2 MicroChannel adapter time-out error 199 User indicated INSTALLED DEVICES list is not correct 2xx Memory (RAM) errors; 201 Memory test failure, error location will be displayed in hexadecimal 202 Memory address error, address lines 00-15 203 Memory address error, address lines 16-13 215 PS/2 motherboard memory failure 216 PS/2 motherboard memory failure 3xx Keyboard errors; 301 Keyboard did not respond to software reset or a stuck key failure was detected. If a stuck key, the scan code for the key is displayed in hexadecimal 302 System unit keylock is locked 303 Keyboard or system unit failure 304 Keyboard or system unit failure; keyboard clock high 305 PS/2 keyboard fuse (on system board) error │ 4xx PS/2 system board parallel port errors; │ 401 PS/2 system board parallel port failure 4xx Monochrome display adapter (MDA) errors; 401 Monochrome memory test, horizontal sync frequency test, or video test failure 408 User indicated display attributes failure 416 User indicated character set failure 424 User indicated 80x25 mode failure 432 Parallel port test failure; monochrome display adapter 5xx Color Graphics Adapter (CGA) errors; 501 CGA memory test, horizontal sync frequency test, or video test failure 508 User indicated display attributes failure 516 User indicated character set failure 524 User indicated 80x25 mode failure 540 User indicated 320x200 mode failure 548 User indicated 600x200 mode failure 6xx Floppy drive/adapter errors; 601 Floppy drive/adapter power on self test failure 602 Drive test failure; disk boot record is not valid 606 Disk chainline function failure; drive error 607 Disk is writeprotected; drive error 608 Bad command; drive error 610 Disk initialization 611 Time-out; drive error 612 Bad controller chip 613 Bad direct memory access; drive error 614 Bad direct memory access; boundry overrun 615 Bad index timing; drive error 616 Drive speed error 621 Bad seek; drive error 622 Bad cyclic redundancy check; drive error 623 Record not found; drive error 624 Bad address mark; drive error 625 Bad controller chip; seek error 626 Disk data compare error 7xx 8087, 80227, or 80397 math coprocessor errors; 9xx Parallel printer adapter errors; 901 Parallel printer adapter test failure * jamie.hermans@tech-spk.alive.ampr.ab.ca or FidoNet: Jamie Hermans @ 1:342/707 ──────────────────────────────────────────────────────────────────────────── Communications Terms ==================== -> Added on November 5, 1994 ╔════════╗ ╔════════╗ ║Computer║ DTE- DCE- DTE- ║Computer║ ║ A ║ Rate ┌─ A ─┐ Rate ┌─ B ─┐ Rate ║ B ║ ║ ╠══════════╡Modem├─────────────┤Modem╞══════════║ ║ ╚════════╝ └─────┘ └─────┘ ╚════════╝ (Figure 1) Pictured above is a brief sketch of a complete signal circuit, consisting of two computers (A & B) interconnected thru their Modems. Five Definitions ~~~~~~~~~~~~~~~~ (as they relate to the above Figure 1) BAUD RATE: The actual rate of signal transitions per second. Since each signal may represent more than one bit, it is not the same as BPS. BPS or Bits Per Second: The number of data bits per second transmitted between two modems. Sometimes incorrectly called the baud rate. (See Baud Rate above) DCE (Data Communication Equipment) rate: The transmission speed of the interface between two modems. The DCE rate and BPS are synonymous. DTE (Data Terminal Equipment) rate: The transmission speed of the interface between a computer / terminal and it's modem. Includes the RS - 232 Serial ports. Baud rate is frequently cited in this interface (*as is bps*), all of which is depicted on Figure 1. Note DTE / baud exists on both ends, while DCE / bps is between the modems. DTE is often called the Port area (and Port Speed) since this is where the Serial Ports are. THROUGHPUT: The DCE rate expressed in cps (Characters/second = bytes/sec). In a modern 9600 bps modem (often incorrectly called a 9600 baud modem) the signal rate is actually 2400 baud. It is encoded with four data bits per baud, resulting in a DCE rate of 9600 bps. The 14,400 bps modem is much the same, but encoded with 6 data bits per baud. In a 2400bps modem (often incorrectly called a 2400 baud modem) the signal rate is actually 600 baud. It is encoded with four data bits per baud, resulting in a DCE rate of 2400bps. The 1200bps modem is much the same, but encoded with only 2 data bits per baud. Since the normal BBS communication schemes employ 8 bits (for each Byte, or character) + 1 start bit, + 1 stop bit = 10 bits/character, it follows that the DCE rate is 10 times the character rate. Therefore a DCE rate of 2400bps results in a Thruput of ~240cps. As this represents a 100% efficiency, this figure is not attainable (without additional techniques), but can be very closely approached using a modern protocol like Zmodem MobyTurbo (tm), which can achieve a thruput of 235 to 238cps on .ZIP'd files. High speed modems usually utilize error correction to exceed the 100% efficiency rate (~1100 cps at 9600 & ~1650 at 14400). MODEM PROTOCOLS ~~~~~~~~~~~~~~~ A variety of ITU-TSS V. standards as well as Microcom MNP standards apply to modems. MODULATION PROTOCOLS ~~~~~~~~~~~~~~~~~~~~ V.17 Emerging ITU-TSS standard for 14400/second FAX. V.17 also supports a more robust 9600 bits/second than V.29 V.21 Transmission at up to 300 bits/second (300 baud) V.22 Transmission at 1200 bits/second (600 baud) V.22bis Transmission at 2400 bits/second (600 baud) V.23 1200 bps ITU-TSS operation with 75 bps back channel (Europe) V.25 Answer sequence for calls originating outside US & Canada V.25bis For Synchronous comm using HDLC & character oriented protocols V.27ter ITU-TSS standard for 2400 & 4800 bit/second (Group III) Fax V.29 ITU-TSS standard for 9600 bit/second (Group III) FAX V.32 Transmission at 4800 & 9600 bits/second (2400 baud) V.32bis Transmission at 4800, 7200, 9600, 12000 & 14400 bps (2400 baud) V.34 Transmission at 2400 to 28800 bps in 2400 steps V.54 Analog, digital and remote digital loopback testing TIA/EIA-578 Service Class 1 Asynchronous Fax DCE Control Standard TIA/EIA-592 Service Class 2.0 Asynchronous Fax DCE Control Standard Note that in the United States of America, Bell 103 and Bell 212a are the protocols that are widely used for 300 and 1200 bps respectively. In Europe, and the rest of the world, V.21 and V.22 are the protocols used for these speeds. ERROR-CONTROL PROTOCOLS ~~~~~~~~~~~~~~~~~~~~~~~ MNP 2-4 Detects and corrects transmission errors. MNP standards do not include full V.42 compliance. Each MNP level adds additional features. The top level, Version 4, strips start and stop bits and optimizes data packets for line conditions. V.42 Handshaking procedure that determines what levels of error correction are common between two modems. LAP-M, a more sophisticated but similar protocol to MNP Level 4, is defined as the primary error correction protocol in V.42 MNP Level 4, providing backwards compatibility with all MNP levels except 1 is recommended as an Annex error correction protocol. Therefore, all V.42 modems should be compatible with all MNP 2-4 modems as well. MNP 10 A set of Adverse Channel Enhancements that helps modems work better with poor connections, compensating for line noise, echo problems, and limited bandwidth. Modems will make multiple attempts to set up a transmission link, optimize the size of data packets for a connection, and adjust to the highest rate possible. The protocol was originally developed to improve connections with cellular modem connections, but it may improve land line connections as well. DATA-COMPRESSION PROTOCOLS ~~~~~~~~~~~~~~~~~~~~~~~~~~ MNP 5 Provides compression as great as 2 to 1 on some files. Not related to V.42bis, but they often appear in the same modems. Slows down compressed file transfers. V.42bis Provides compression as great as 4 to 1 on some files. Doesn't itself include MNP 5 compatibility, and will not slow down transfer of compressed files. T.4 Specifications for encoding FAX data according to one of several possible compression algorithms. T.30 A standard for controlling the handshake of two Group III FAX devices. It sets negotiations between devices for speed and data encoding, and sends a 1100 hertz communications tone between devices. NOTE: Each V.nnbis complements, but is separate from, its V.nn counterpart. Theo Irmer, director of the ITU-TSS wrote: "I would like you to note further, that the use of "bis", "ter" etc. in the numbering of Recommendations (e.g. V.42bis) does not necesarily mean a simple expansion of the Recommendation having the original number, (e.g. V.42). In other words, V.42 and V.42bis should be considered as independent, separate Recommendations." A discussion of proprietary modulation protocols -- Compucom CSP, Hayes Express, Microcom MAX, Telebit PEP, & USR HST -- is beyond the scope of this primer, except to emphasize that ALL proprietary's will connect at Hi Speed with ONLY THEIR OWN; ie HST to HST, PEP to PEP, etc. This includes v.FC, which is not a standard of any kind, though many manufacturers support or will support it in their V.34 modems. UARTs: Universal Asynchronous Receiver/Transmitters are required elements in the signal circuit to convert the parallel transmission to serial (in the serial port--or COM port). For systems using external modems, the terminal UART is employed. Internal modems, however, make use of their own internal UART. Most commonly supplied in these cases is the 8250 or (in AT's) the 16450. For the majority of users, these chips will suffice for 9600+ bps DCE rates. Some systems, however, that are experiencing interrupt latency (IL) are liable to experience data overruns and lost bits when using the stock UARTs. If you fit into that category, you will likely require an NS16550AFN (now known also as the PC16550CN), a direct plug-in replacement for the above named UARTs. The 16550 has onboard 16 byte FIFO buffers (transmit & receive) to retain the otherwise lost bits, during IL occurrences. The factors that increase the IL risk are: slow hardware, fast modems, multitasking, and other CPU intensive software. Because you fit the IL profile does NOT mean you require a 16550, just a higher risk. If you ARE losing bits during xfers, however, you should definitely consider the 16550. Sometimes this means switching to a separate plug-in serial card (and external modem) in order to incorporate the new chip. * Bob R. -=- International COMM Echo Moderator -=- @ 1:154/40 ──────────────────────────────────────────────────────────────────────────── IDE and SCSI drives (RE: 32bit access) ====================================== -> Added on October 30, 1994 -> Windows for Workgroups First, make sure your Windows swap file is located on your IDE drive. Next, configure Control Panel / 386Enh / virtual memory for 32-bit DISK access and 32-bit FILE access. Add these following two lines to the [386Enh] section of SYSTEM.INI: device=vxdldr.386 device=ios.386 This will enable the "real mode remapper". Now restart Windows. If Windows hangs, reboot and comment out the following line from the [386Enh] section of SYSTEM.INI and restart Windows once again: NoEMMDriver=True * This is a known and proven bug in Microsoft WFWG 3.11 that occurs under special conditions. At this point, your IDE drive should have both 32-bit DISK access and 32-bit FILE access. Your SCSI drive should have 32-bit FILE access only. * Unknown InterNet Newsgroup Post ──────────────────────────────────────────────────────────────────────────── Connecting Two Network Cards ============================ -> Added on October 30, 1994 QUESTION: "I have two computers both with WFW 3.11 installed. I would like to share resoures and drives. I have the opportunity to use a 3COM network card and an Allied Telesys network card. That plus a length of 8 conductor twisted pair cable terminated with RJ45 connectors. I also have the network card drivers that came OEM. Will this work - or is there more hardware & software required? Does one of the computers or another computer have to be setup as server? Do I require a hub to interconnect the computers through?" ANSWER: After you get the cards configured and installed you can avoid the hub by swapping the transmit and receive pairs of your cable. 1 2 3 4 5 6 7 8 │ │ │ │ │ │ │ │ Connecting Cable │ │ │ │ │ │ │ │ 3 6 1 4 5 2 7 8 Active pins are 1 & 2 and 3 & 6, one end is normal, one end swapped. Also keep in mind that pairs should be kept together to keep twists from end to end, the twists are what keeps out RF and EF interference. So pair 1 & 2 and 3 & 6 should twist from end to end. * Mark Wright @ 1:343/105 ──────────────────────────────────────────────────────────────────────────── Remote Access at Higher Speeds ============================== -> Added on October 30, 1994 First this procedure is not recommended by Microsoft, but I am successfully running it on several WFW3.11 workstations, 2 NTAS 3.1 servers, and the Daytona BETA. Basically they don't want you to manually edit the .INF or the .INI files. First step is to backup the MODEM.INF file!! Next you need to have a suggested settings section for the .INF file and add this to the MODEM.INF If the manufacture doesn't have a suggested settings for your 28.8 modem, then find a modem close to the one you have, ie USR Courier D/S for the USR Courier D/S 28.8. Copy the section of the .INF file that is similiar to the one you need. Paste the section back in the MODEM.INF file under the original section. Change the name of the section in brackets to a different name you will recognize later (I add 28.8 to the end). Now you need to edit the following lines in the new section: MAXCARRIERBPS=14400 change this to 28800 MAXCONNECTBPS=19200 change this to 57600 if you have a 16550 uart otherwise change this to 38400 If you don't have a 16550, I'd suggest getting one. RAS will work at 28.8 with the DTE set to 38400, but you will probably get serial over-run errors especially if modem compression is turned on. Now save the file and reconfigure RAS. Your "new" modem will be one of the entries you can choose. I have heard of problems with modem compression causing serial overruns even at 57600. So try it with compression on, if you have problems turn it off. RAS at 28.8 is actually workable. Files transfers are quick, but if you have noisy lines be carefull because RAS uses the network protocols not an error correcting protocol like zmodem. * Unknown Newsgroup Post ──────────────────────────────────────────────────────────────────────────── USRobotics Sportster Modem ========================== -> Added on October 30, 1994 The proven initialization string for the USR Sportster is as follows. Type AT&F to reset to factory defaults before entering and saving (AT&W) the new settings. AT&B1&N0&H1&K3&A1&M4&I0&R2S10=15V1X4S27=32 After you save the settings, use ATZ as your Modem Init string in all the programs that use it. You should regularily achieve 1650 cps on a Zmodem download on normal phone lines. * jeff.marchi@pcgfx.com (If you want to enter this in the initialization string slot of your comm prog then add ^M directly at the end of the string). Steps to utilizing this string: 1) Go to the Terminal screen and type AT&F <enter> to restore your factory defaults. 2) CAREFULLY type this string to the Terminal window *exactly* as above. Hit the <enter> key. When you get the "OK" signal ... 3) Type AT&W <enter>. This will save the string in your NVRAM. 4) Change your init string in Telemate to ATZ^M, and this will activate your NVRAM settings each time you initialize or return to Originate Mode. If you want a faster dial sequence than default (S11-70), then type ATS11=50&W this will speed up the dial sequence and save it to NVRAM. Again, having ATZ as your Telemate init string will utilize your NVRAM settings. The following is a quick breakdown of what the commands in this string do: 1) &B1 This locks the serial port at the speed you have set (this should be 38400 for 14400s; 19200 for 9600s). 2) &N0 This allows variable rate connections. 3) &H1 Enables hardware flow control (CTS). 4) &K3 Disables MNP5 data compression while still allowing Selective Data Compression based on V.42bis. MNP5 is not useful for already compressed files...in fact it adds data to the files thus degrading performance. 5) &A1 This enables ARQ error control result codes. 6) &M4 Normal or default ARQ error control is enabled. 7) &I0 Xon/Xoff software flow control is disabled. 8) &R2 RTS (hardware flow control) is enabled. 9) S10=15 Delay of 1.5 seconds before hang-up if carrier is lost. 10) V1 Verbal Result Codes is enabled. 11) X4 Recognizes all result codes (default). 12) S27=32 Disabled V.42 (enabled MNP). * Gordon Vanscheik @ 1:3417/2 Some Sportsters were sold that had Dual Standard ROMS in them. There is a "magic" string that you can enter and your modem will turn into and stay as a 16800 Courier Dual Standard. To verify the change, type ATI4 or ATI5 in a communications program. The modem will not return to a Sportster until it loses power, resetting by ATZ will not do it! This only works with certain dated ROMS! ATGW03C6,22GW05CD,2F * tony.madsen@freddy.supernet.ab.ca ──────────────────────────────────────────────────────────────────────────── Connecting Two Modems ===================== -> Added on October 30, 1994 If you're on a voice call with someone and want to transfer a file or do something over the modem, use this little trick to save yourself from the need to hang up and redial. Make sure both modems are initialized and ready, then type the following commands: ATX3D on one computer ATA on the other one It doesn't matter which computer uses which command, but you can't use the same on both. * jamie.hermans@tech-spk.alive.ampr.ab.ca or FidoNet: Jamie Hermans @ 1:342/707 ──────────────────────────────────────────────────────────────────────────── SHHHH ... Quite! ================ -> Added on October 30, 1994 Doing some late night modemming? Turn the speaker down with ATL0 or L1. Turn it completely off with ATM0. * PC Computing - August 1994 ──────────────────────────────────────────────────────────────────────────── Sluggish Compression? ===================== -> Added on October 30, 1994 If you have a 386 or faster, and are using DoubleSpace, you can speed things up a little bit. First, type "DBLSPACE /INFO" to locate the uncompressed drive containing the compressed file DBLSPACE.000. Go to the root directory of that drive and type "ATTRIB -S -H -R DBLSPACE.INI". Now edit DBLSPACE.INI and add "Enable386=1" as it's own line. Save and exit the editor and at the prompt type "ATTRIB +S +H +R DBLSPACE.INI". Reboot for the change to take effect. * PC Computing - August 1994 This has been tested with the new DriveSpace (DOS 6.22) and appears to work just fine. Simply substitute "DRVSPACE.*" with "DBLSPACE.*" in the example above. * jamie.hermans@tech-spk.alive.ampr.ab.ca or FidoNet: Jamie Hermans @ 1:342/707 ────────────────────────────────────────────────────────────────────────────