The "Information Alley", Volume 2, Issue 8 -- August 7, 1995
Copyright 1994-95, Apple Computer, Inc.
The "Information Alley" is a publication of Apple Computer, Inc., Support Information Services. It is available to all Apple customers and Apple computer users through a variety of online services.
The goal of the "Information Alley" is to help Apple computer users get full use of their Apple computers, peripherals, and software. Feel free to distribute the "Information Alley" to anyone.
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Contents of Part 1 of 2
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Thoughts From the Alley Cat -- Font Problem Found and Fixed
Apple Software Updates Information Available via email
New Color StyleWriter Pro Black Ink Cartridge
Power Macintosh 9500 -- Video Blinking at Startup
Energy Saving Control Panels
Starting Your Performa From a CD-ROM Disc
Using the Chinese Language Kit on a Power Macintosh 9500 Series Computer
QuickDraw GX 1.1.2 -- Desktop Printer Icons Do Not Stay Put
Printing White Text on Black from HyperCard in QuickDraw GX
Contents of Part 2 of 2 (this document)
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Disk/Disk or Directory/Directory Copy Between AWS 95 and A/UX
Apple Open Transport
AppleShare 4.1 Update Kit Information
Slow External Mouse on a PowerBook 500 Series Computer
Apple LaserWriters -- Screen Frequency and Gray Levels
Extra Floppy Disk Shows in the Main Window When Using Disk First Aid
Disk/Disk or Directory/Directory Copy Between AWS 95 and A/UX
This article describes how to copy all the files in the root (/) partition between an Apple Workgroup Server 95 and A/UX, without loosing access privileges and without having to recreate the /dev directory. The following commands create a duplicate of the directory structure of the source drive onto the target drive. You can also use this command sequence to copy a directory tree from one directory to another.
* To Copy The Complete Contents Of A Partition
Complete the steps in the following table while logged in as root:
Step 1
Mount the partition you want to copy to (target) on /mnt:
mount /dev/dsk/c5d0s0 /mnt
NOTE: Replace SCSI ID and partition as appropriate.
Step 2
Go to the / directory:
cd /
Step 3
Perform the copy preventing the copy from becoming recursive and without overwriting the lost+found directory in the target partition:
Now you have a copy of the source drive, complete with the /dev directory.
* To Create a Duplicate of a Directory Structure
Step 1
Go to the directory containing the source directory to be copied:
cd /a_directory
Step 2
Perform the copy of the source_dir to the directory where you want the source_dir structure to be moved to:
find source_dir -print | cpio -pdlmuv /target_dir
This results in a directory called source_dir inside of target_dir.
Apple Open Transport
--------------------
By Fred Widmer
Open Transport provides individual computer users with many benefits. Two of the most visible and important benefits relate to making networking more accessible:
* Ease of Switching Network Configurations
Open Transport makes it easy to switch from one network
configuration to another. A computer user "on the go" might want
to connect to the Internet in various locations, each requiring a different network configuration. With Open Transport, settings for each network location can be stored for easy access and use. Changed settings are available immediately – no restart of the computer is required to use the new configuration.
* Integrated Online Help
Open Transport integrates online help, based on Apple Guide technology, to make it easier for an individual to connect to a network, with fewer demands on network manager and support resources.
Open Transport provides significant new flexibility in setting up network configurations. A network manager can recommend or require configuration settings for users on the network, or allow users to determine their own settings.
Open Transport also improves support for centralized configuration management. For example, Open Transport/TCP supports the Dynamic Host Configuration Protocol (DHCP), letting network managers administer addressing and other TCP/IP configuration information from a central server.
Open Transport makes it easier and more cost-effective to develop Macintosh-based applications for a wide variety of customers. With Open Transport, the Mac OS has built-in networking and communications based on cross-platform industry standards, including the POSIX compliant X/Open Transport Interface (XTI), Unix STREAMs and Data Link Provider Interface (DLPI). Applications written to support Open Transport can directly support a wide range of networking environments (serial, dial-up network, LAN, and WAN), and multiple protocols (AppleTalk, TCP/IP, serial, and others) from a common code base.
* Questions and Answers About Performance
Question: Is Open Transport native on Power Macintosh? Does this make networking faster?
Answer: Open Transport is written to take advantage of the PowerPC processor -- it is native code. This provides the necessary foundation for increased networking performance in the Mac OS. To realize performance gains, however, it is equally important that networking applications also be accelerated for Power Macintosh, and that applications adopt the new Open Transport XTI-based programming interfaces.
The built-in "backward compatibility" support for existing AppleTalk and TCP/IP applications continues, for technical reasons, to run as 680x0 code in emulation on Power Macintosh. This protects a customer's investment in networking applications, but also obscures underlying performance increases from the native protocol implementations.
Question: When will new or updated applications that support the native Open Transport APIs become available?
Answer: Some new applications and updated versions of existing applications are native and use Open Transport now. More will be shipping this year. Contact the specific third-party vendor for more details on their product release plans.
Question: How much faster will native Open Transport applications be?
Answer: Networking performance is influenced by many factors. Customers will see the highest performance networking when using Power Macintosh native applications that fully support Open Transport APIs. Performance will be greater with protocols that use larger datagram sizes—such as TCP/IP—than with AppleTalk (which has a fixed and limited datagram size). On high-speed datalinks (such as fast Ethernet, FDDI, and ATM), the performance of the network interface card (NIC) driver code is also a significant factor. Comparative shopping for NICs – based on price, service, reliability, and performance -- will be in order.
Open Transport v1.0 - running on the built-in Ethernet of the Power Macintosh 9500 – has been clocked at 9,300 Kbps throughput using low-level TCP/IP benchmarks. A pre-release version of a third party Open Transport-native implementation of 'nfs' protocols was benchmarked at 8,400 Kbps. Both figures approach theoretical maximum performance for 10 Mbps Ethernet. AppleTalk performance is somewhat lower, with low-level benchmarking coming in at a bit over 7,500 Kbps throughput.
Question: Does the new native code include Ethernet drivers for Macintosh onboard Ethernet adapters?
Answer: The Power Macintosh 9500 ships with a new native DLPI Ethernet driver for built-in Ethernet. Future PCI bus Macintosh computers also include native Ethernet drivers. Power Macintosh 61xx/71xx/81xx models currently have 680x0-based drivers; these should be updated to native drivers in the first half of 1996.
Question: What about high-speed networking connections like fast Ethernet, ATM, and FDDI?
Answer: The Open Transport engineering team is working with NIC developers to create high-performance DLPI drivers for high-speed datalinks. This is a cooperative effort, with some work remaining on both driver code and on Open Transport. We expect that high-speed datalink NIC drivers based on Open Transport v1.1 will be fully competitive with other PCI networking products. Of course, performance tuning will be an ongoing priority, as Apple intends to always offer a platform capable of industry leading network performance.
Question: Will developers ship NICs for fast Ethernet, FDDI, or ATM based on Open Transport v1.0, or will they wait for the performance tuning planned for v1.1?
Answer: Each developer will make an independent decision to bring their product to market at such time as they are satisfied with the combined performance and reliability of their product with Open Transport.
AppleShare 4.1 Update Kit Information
-------------------------------------
By Terrie Beloin
AppleShare 4.1 is the latest release of AppleShare for the Mac OS. It is also the fastest AppleShare ever. While AppleShare 4.1 is not PowerPC native, it is tuned to run on PowerPC-based systems and will not install or run on 68K-based Macintosh computers.
AppleShare 4.1 runs, on average, 75% faster than AppleShare 4.0.2 on a similarly configured Power Macintosh or Workgroup Server. All performance data for AppleShare 4.1 is based on a set of internal benchmarks performed by Apple. These benchmarks consist of a variety of Finder copy operations under varying server load conditions.
AppleShare 4.1 requires System 7.5 on the server to run and requires System 7.5 and the new AppleShare Workstation 3.6 (included with AppleShare 4.1) on the client systems to achieve the performance gains detailed above. However, AppleShare 4.1 is compatible with older versions of the AppleShare Workstation software and AppleShare Workstation 3.6 is compatible with older versions of the AppleShare server software.
* How to Order the AppleShare 4.1 Update Kit
Customers in the U.S. wanting to upgrade from AppleShare 4.0, 4.0.1 or 4.0.2 to AppleShare 4.1 need to obtain the AppleShare 4.1 Update Kit (proof of 4.0.x purchase is required). The update can be obtained by calling the Apple Order Center at 1-800-769-2775 x7851. This program began April 24, 1995 and ends December 29, 1995. Orders must be postmarked by December 29, 1995.
- Customers running AppleShare 4.0.2 on a PowerPC-based Workgroup Server (6150, 8150, or 9150) will receive the AppleShare 4.1 Update Kit for a $15 shipping/handling charge only. These customers will also receive the Workgroup Server Software Update Kit containing System 7.5.1 for Workgroup Servers and Apple RAID 1.0.2.
- Customers running AppleShare 4.0, 4.0.1 or 4.0.2 on a 68040 or Power Macintosh will receive the AppleShare 4.1 Update Kit for $199 + $15 shipping/handling.
The AppleShare 4.1 Update Kit contains the complete AppleShare 4.1 software but no serial number. Customers must use their existing AppleShare 4.0.x serial number to activate the server. The AppleShare 4.1 Update Kit will be included with the Workgroup Server 8150/110 and 9150/120 Logic Board Upgrades.
Outside the U.S., customers should contact their local Apple reseller or representative for information on upgrading to AppleShare 4.1 in their local language.
* AppleShare 4.0.2 and 3.0.1 Continued Availability
Customers wanting to repurpose an existing Quadra (or other 68040-based Macintosh) as an AppleShare server can do so by purchasing AppleShare 4.0.2 from their Apple Reseller. AppleShare 4.0.2 is designed for 68040-based Macintosh computers only and will not install or run on PowerPC-based systems. AppleShare 3.0.1 continues to be available for Macintosh computers with a 68030 or earlier processor.
For more information on AppleShare and Workgroup Servers, customers can contact the Apple Network Information Hotline at 408/862-3385 or send email to:
abs.netinfo@applelink.apple.com.
World Wide Web access is available at:
http://abs.apple.com
Slow External Mouse on a PowerBook 500 Series Computer
This article describes what is happening when you connect an external mouse to a PowerBook 540c and the mouse tracks slowly (even if the Mouse control panel is set to Fast).
It is very important that you do not plug the mouse into the ADB port when the computer is "powered on". This may damage the ADB port or mouse. However, it is safe to plug in the ADB device when the Macintosh PowerBook 540c is in the sleep mode.
Plugging in a mouse device on any Macintosh computer while the unit is powered on can result in slow mouse (cursor) movement and possible damage to the ADB port. In addition, the Macintosh PowerBook 500 series computers have two control panels influencing the speed of movement of the cursor: the Trackpad and Mouse. Their settings are related to each other. When you make a change in the Trackpad control panel, the Mouse control Panel also changes.
Check to make sure the Trackpad and Mouse control panels are set to the same speed. Open the Mouse control panel and click on the speed you want, even if the speed is already selected. By clicking on the speed you will be sure to save that setting. Do the same for the Trackpad control panel.
Apple LaserWriters -- Screen Frequency and Gray Levels
This article discusses customizing printer halftones, screen frequency, and gray levels for optimum output.
Determining the optimal relationship between gray levels and screen frequency is quite simple once you understand a few basic concepts of laser printers. Like computers, laser printers understand only two values: on and off (black and white). They simulate grays by varying the amount of dots within a certain area, called a halftone grid. Halftones are made of grids, just like the paper used to graph functions in trigonometry. To create a halftone, laser printers place dots within each cell on the grid. The screen frequency (which is a misnomer these days, but we still use the term leading when talking about the space between lines of text) determines the size of each cell in the grid.
Most laser printers can produce only a given size dot, however Photograde is the exception. Because the dot size is fixed and increasing the line frequency decreases the size of each cell, the gray levels which can be produced are inversely proportional to the line frequency. Visualize a grid and keep in mind only so many dots can be placed on a region of paper. In a 600 dpi printer, such as a LaserWriter Select 360, the dpi does not vary, but you can vary the size of the grid. Because printers produce grays by varying the amount of dots within each halftone cell, making the cells smaller will allow fewer grays in your halftone. The following formula lets you easily determine how many grays you can get for a given resolution and screen frequency with an angle of 0 degrees.
(600 dots per inch / 100 lines per inch)^2 + 1 = 61 Gray Levels
With a little juggling, you can also use this formula to determine what screen frequency yields a desired level of grays. For a bit easier calculation, simply divide the dots per inch by the square root of the grays levels to determine the screen frequency:
Dots Per Inch times / sqrt(Gray Levels) = Screen Frequency
Staying with the Select 360 example, if you want 100 gray levels:
600 / sqrt(100) = 60
Again, you can rearrange this formula to calculate different variables. Keep in mind Postscript is limited to 256 shades of gray, so your largest divisor in the preceding formula will be 16. Even for high-end work though, Postscript does an excellent job. Plug a 150 line screen into the formula and you will see you need a 2,400 dpi printer to produce 256 grays.
The discussion above holds true for fixed resolution printers, but Photograde changes the rules by varying the timing of the laser pulses to vary the size of the dots within each cell. The LaserWriter Pro 600/630, Select 300 and IIf/IIg use Photograde technology. Photograde is capable of producing 91 levels of grays using a 106 line screen at 300 dpi. This is sufficient for proofing photographs and low-quality newsletter output.
Also keep in mind 300 dpi and 600 dpi laser printers cannot replace imagesetters or traditional darkroom halftones. Some 1,200 dpi laser printers can produce acceptable halftones for reproducing on newsprint, but users will have to experiment with dot shape and line angle to determine what works best with their particular printer and press. The best solution is to output final copy directly to film on an imagesetter and use laser printers for proofing.
Extra Floppy Disk Shows in the Main Window When Using Disk First Aid
There have been reports of a problem using Disk First Aid 7.2 after starting up from Disk Tools. When Disk First Aid's main window opens you see the Disk Tools disk on the Internal Floppy Drive, the SCSI ID 0 for the hard drive, and a third floppy disk named "unknown disk".
This issue has been occasionally reported to occur on PowerBooks. You should first make sure you do not have a RAM disk turned on in the memory control panel. To remove the extra floppy icon, you must reset your parameter ram using the following procedure:
Step 1
Restart your computer.
Step 2
After you hear the startup chime hold down the Command, Option, P, and R keys on the keyboard.
Step 3
Continue holding these keys down until you hear a second startup chime.
When you restart with the Disk Tools disk and run Disk First Aid, the extra floppy will be gone.
*** End of Part 2 of 2, Information Alley, Volume 2, Issue 8, 7 August 95 ***
