Layout of the Archive

The ZY Boot Diskette Archive (BDA) is exported by freya under the share name

   \\FREYA\LaserComputerSystems

This archive consists of directories and files under this file system share, and require no tools other than the operating system's shell to access (see figure A.1).

Figure A.1: ZY Boot Diskette Archive, as seen from the Windows NT 4.0 Explorer.

The structure of the archive can be seen graphically in figure A.1. The root directory of the archive contains subdirectories dedicated to each major type of system (VY, ZY etc). Within the ZY directory there exists a directory for each individual ZY system deployed by the GBT Metrology Group. The directory of ZY102 is representative of all others in the archive. As can be seen in the figure, this directory contains a subdirectory named diskimage, and another named full_pctcp. The diskimage directory contains all of the files and the subdirectory hierarchy necessary to make this ZY work properly:

NDIS: This subdirectory contains the packet drivers and their configuration files to allow the networking software to interface with the provided Network Interface Card (NIC) hardware. The NIC may be an EtherLink II, EtherLink III or an Allied Telesis AT1700 (see subsection A.2.2).

PCTCP: This subdirectory contains the FTP Software PC/TCP network software that provides the ZY with TCP/IP capability. To conserve space on the boot diskette, this subdirectory contains only the files necessary for the operation of the ZY. The full PC/TCP installation is provided elsewhere in subdirectory full_pctcp, in case any utility may be needed for any unforseen purpose (see subsection A.2.3).

AUTOEXEC.BAT: The all-important AUTOEXEC.BAT file sets the DOS environment, starts up the networking software, sets the time using an NTP client, downloads the ZY and finally executes the ZY (see subsection A.2.4).

CONFIG.SYS: This file is used primarily to run the network packet driver and packet to NDIS converter driver. It also sets various operating system parameters, such as the DOS file handles and file buffers (see subsection A.2.5).

RLOAD.EXE: This file, run by the AUTOEXEC.BAT batch file, downloads the ZY program from the ZIY host (see subsection A.2.6).

In addition to the diskimage directory, each ZY/VY subdirectory contains a subdirectory called full_pctcp, which contains the full PC/TCP installation for that ZY/VY. The full PC/TCP installation is too large to fit on the ZY boot diskette, nor is it needed for the proper operation of the ZY. However, one or more of the files in this directory may be needed for the boot diskette to deal with unforseen circumstances (troubleshooting, etc). This directory makes it easy to retrieve the needed file or utility without having to re-install the PC/TCP installation somewhere.