Functionally, the CHMOS devices (designated with
“C” in the middle of the device name) me all fiuy
compatible with the 8051, but being CMOS, draw less
current than an HMOS counterpart. To further exploit
the power savings available in CMOS circuitry, two re-
duced power modes are added
l Software-invoked Idle Mode, during which the CPU
is turned off while the RAM and other on-chip
peripherals continue operating. In this mode, cur-
rent draw is reduced to about 15% of the current
drawn when the device is fully active.
A profile is a named set of the following password and resource limits:
Password aging and expiration
Password complexity verification
Input/output (I/O) operations
Memory space (private SQL area for Shared Server only)
After a profile has been created, the database administrator can assign it to each user. If resource limits are enabled, the Oracle server limits the database usage and resources to the defined profile of the user....
The CPU contains a special set of memory cells called registers that can be read and written to much more rapidly than the main memory area. There are typically between two and one hundred registers depending on the type of CPU. Registers are used for the most frequently needed data items to avoid having to access main memory every time data is needed. As data is constantly being worked on, reducing the need to access main memory (which is often slow compared to the ALU and control units) greatly increases the computer's speed....
Cái gì gọi các hoạt động của CPU?
Hệ thống bó (Batch system): jobs
Time-shared systems: user programs, tasks
Các hoạt động là tương tự = gọi là process
Quá trình (process)
một chương trình đang thực thi
Một quá trình bao gồm
Text section (program code), data section (chứa global variables)
program counter (PC), process status word (PSW), stack pointer (SP), memory management registers,…