參數(shù)資料
型號(hào)： COP8SAB7SLB9
廠商： NATIONAL SEMICONDUCTOR CORP
元件分類： 微控制器/微處理器
英文描述： 8-Bit CMOS ROM Based and One-Time Programmable OTP Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging
中文描述： 8-BIT, OTPROM, 10 MHz, MICROCONTROLLER, QCC28
封裝： CSP-28
文件頁(yè)數(shù)： 22/60頁(yè)
文件大?。?/td> 787K
代理商： COP8SAB7SLB9
7.0 Timers
(Continued)
7.2.3 Mode 3. Input Capture Mode
The device can precisely measure external frequencies or
time external events by placing the timer block, T1, in the in-
put capture mode. In this mode, the reload registers serve as
independent capture registers, capturing the contents of the
timer when an external event occurs (transition on the timer
input pin). The capture registers can be read while maintain-
ing count, a feature that lets the user measure elapsed time
and time between events. By saving the timer value when
the external event occurs, the time of the external event is
recorded. Most microcontrollers have a latency time be-
cause they cannot determine the timer value when the exter-
nal event occurs. The capture register eliminates the latency
time, thereby allowing the applications program to retrieve
the timer value stored in the capture register.
In this mode, the timer T1 is constantly running at the fixed t
C
rate. The two registers, R1A and R1B, act as capture regis-
ters. Each register acts in conjunction with a pin. The register
R1A acts in conjunction with the T1A pin and the register
R1B acts in conjunction with the T1B pin.
The timer value gets copied over into the register when a
trigger event occurs on its corresponding pin. Control bits,
T1C3, T1C2 and T1C1, allow the trigger events to be speci-
fied either as a positive or a negative edge. The trigger con-
dition for each input pin can be specified independently.
The trigger conditions can also be programmed to generate
interrupts. The occurrence of the specified trigger condition
on the T1A and T1B pins will be respectively latched into the
pending flags, T1PNDA and T1PNDB. The control flag
T1ENA allows the interrupt on T1A to be either enabled or
disabled. Setting the T1ENA flag enables interrupts to be
generated when the selected trigger condition occurs on the
T1A pin. Similarly, the flag T1ENB controls the interrupts
from the T1B pin.
Underflows from the timer can also be programmed to gen-
erate interrupts. Underflows are latched into the timer T1C0
pending flag (the T1C0 control bit serves as the timer under-
flow interrupt pending flag in the Input Capture mode). Con-
sequently, the T1C0 control bit should be reset when enter-
ing the Input Capture mode. The timer underflow interrupt is
enabled with the T1ENA control flag. When a T1A interrupt
occurs in the Input Capture mode, the user must check both
the T1PNDA and T1C0 pending flags in order to determine
whether a T1A input capture or a timer underflow (or both)
caused the interrupt.
Figure 17 shows a block diagram of the timer in Input Cap-
ture mode.
DS012838-24
FIGURE 17. Timer in Input Capture Mode
www.national.com
22
相關(guān)PDF資料
PDF描述
COP8SAC7SLB9 8-Bit CMOS ROM Based and One-Time Programmable OTP Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging
COP8SAA5 8-Bit CMOS ROM Based and One-Time Programmable OTP Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging
COP8SAA7 8-Bit CMOS ROM Based and One-Time Programmable OTP Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging
COP8SAA716N9 8-Bit CMOS ROM Based and One-Time Programmable OTP Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging
COP8SAA720M8 8-Bit CMOS ROM Based and One-Time Programmable OTP Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
COP8SAC5 制造商:NSC 制造商全稱:National Semiconductor 功能描述:8-Bit CMOS ROM Based and One-Time Programmable OTP Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging
COP8SAC7 制造商:NSC 制造商全稱:National Semiconductor 功能描述:8-Bit CMOS ROM Based and One-Time Programmable OTP Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging
COP8SAC720 制造商:NSC 制造商全稱:National Semiconductor 功能描述:8-Bit CMOS ROM Based and One-Time Programmable OTP Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging
COP8SAC720M7 制造商:NSC 制造商全稱:National Semiconductor 功能描述:8-Bit CMOS ROM Based and One-Time Programmable (OTP) Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging
COP8SAC720M8 功能描述:8位微控制器 -MCU RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*