参数资料
型号: P8254
厂商: Intersil Corporation
英文描述: CMOS Programmable Interval Timer
中文描述: CMOS可编程间隔定时器
文件页数: 12/17页
文件大小: 142K
代理商: P8254
4-12
Counter
New counts are loaded and Counters are decremented on
the falling edge of CLK.
The largest possible initial count is 0; this is equivalent to 2
16
for binary counting and 10
4
for BCD counting.
The counter does not stop when it reaches zero. In Modes 0,
1, 4, and 5 the Counter “wraps around” to the highest count,
either FFFF hex for binary counting or 9999 for BCD count-
ing, and continues counting. Modes 2 and 3 are periodic; the
Counter reloads itself with the initial count and continues
counting from there.
FIGURE 15. GATE PIN OPERATIONS SUMMARY
FIGURE 16. MINIMUM AND MAXIMUM INITIAL COUNTS
SIGNAL
STATUS
MODES
0
1
LOW OR
GOING LOW
Disables Counting
-
RISING
-
HIGH
Enables Counting
-
1) Initiates
Counting
2) Resets output
after next clock
Initiates Counting Enables Counting
2
1) Disables
counting
2) Sets output im-
mediately high
1) Disables
counting
2) Sets output im-
mediately high
1) Disables
Counting
-
3
Initiates Counting Enables Counting
4
-
Enables Counting
5
Initiates Counting
-
MODE
MIN COUNT
MAX COUNT
0
1
0
1
1
0
2
2
0
3
2
0
4
1
0
5
1
0
NOTE: 0 is equivalent to 2
16
for binary counting and 10
4
for BCD
counting.
82C54
相关PDF资料
PDF描述
P8257 PROGRAMMABLE DMA CONTROLLER
P82586 IEEE802.3 ETHERNET LAN COPROCESSOR
P82588 LAN Node Controller
D82588 LAN Node Controller
P82590 LAN Node Controller
相关代理商/技术参数
参数描述
P82542 制造商:Intel 功能描述:
P8254-2 制造商:Rochester Electronics LLC 功能描述:
P8255A 制造商:INT 功能描述:F8255 INTEL S7G6B
P8255A5 制造商:未知厂家 制造商全称:未知厂家 功能描述:Peripheral Miscellaneous
P8255A-5 制造商:Intel 功能描述: 制造商:ADV_MICRO_SYS 功能描述: 制造商:Rochester Electronics LLC 功能描述: