System information

SYSGEN image: Memory image of the CP/M system created by SYSGEN when a destination
drive is not specified. This is the same as the MOVCPM image that can be read by SYSGEN if a
source drive is not specified. See MOVCPM image.
system attribute (SYS): File attribute. You can give a file the system attribute by using the SYS
option in the STAT command or by using the set file attributes function, BDOS Function 12. A
file with the SYS attribute is not displayed in response to a DIR command. If you give a file with
user number 0 the SYS attribute, you can read and execute that file from any user number on the
same drive. Use this feature to make your commonly used programs available under any user
number.
system prompt: Symbol displayed by the operating system indicating that the system is ready to
receive input. See prompt and CP/M prompt.
system tracks: Tracks reserved on the disk for the CP/M system. The number of system tracks
is specified by the parameter OFF in the disk parameter block (DPB). The system tracks for a
drive always precede its data tracks. The command SYSGEN copies the CP/M system from the
system tracks to memory, and vice versa. The standard SYSGEN utility copies 26 sectors from
track 0 and 26 sectors from track 1. When the system tracks contain additional sectors or tracks
to be copied, a customized SYSGEN must be used.
terminal: See console.
TPA: Transient Program Area. Area in memory where user programs run and store data. This
area is a region of memory beginning at 0100H and extending to the base of the CP/M system in
high memory. The first module of the CP/M system is the CCP, which can be overwritten by a
user program. If so, the TPA is extended to the base of the CP/M BDOS module. If the CCP is
overwritten, the user program must terminate with either a system reset (Function 0) call or a
jump to location zero in page zero. The address of the base of the CP/M BDOS is stored in
location 0006H in page zero least significant byte first.
track: Data on the disk media is accessed by combination of track and sector numbers. Tracks
form concentric rings on the disk; the standard IBM single-density disks have 77 tracks. Each
track consists of a fixed number of numbered sectors. Tracks are numbered from zero to one less
than the number of tracks on the disk.
Transient Program Area: See TPA.
upward compatible: Term meaning that a program created for the previously released operating
system, or compiler, runs under the newly released version of the same operating system.
USER: Term used in CP/M and MP/M systems to distinguish distinct regions of the directory.
Appendix H : Glossary CP/M Operating System Manual
H-18