參數(shù)資料
型號: T89C51RD2-DDFI-L
廠商: Atmel Corp.
英文描述: IC - OPTOISOLATOR 4N28
中文描述: 0至40MHz可編程閃存8位微控制器
文件頁數(shù): 122/170頁
文件大?。?/td> 1927K
代理商: T89C51RD2-DDFI-L
122
A/T89C51CC01
4129L–CAN–08/05
Programmable
Counter Array (PCA)
The PCA provides more timing capabilities with less CPU intervention than the standard
timer/counters. Its advantages include reduced software overhead and improved accu-
racy. The PCA consists of a dedicated timer/counter which serves as the time base for
an array of five compare/capture modules. Its clock input can be programmed to count
any of the following signals:
PCA clock frequency/6 (see “clock” section)
PCA clock frequency/2
Timer 0 overflow
External input on ECI (P1.2)
Each compare/capture modules can be programmed in any one of the following modes:
rising and/or falling edge capture,
software timer,
high-speed output,
pulse width modulator.
Module 4 can also be programmed as a Watchdog timer. see the "PCA Watchdog
Timer" section.
When the compare/capture modules are programmed in capture mode, software timer,
or high speed output mode, an interrupt can be generated when the module executes its
function. All five modules plus the PCA timer overflow share one interrupt vector.
The PCA timer/counter and compare/capture modules share Port 1 for external I/Os.
These pins are listed below. If the pin is not used for the PCA, it can still be used for
standard I/O.
PCA Timer
The PCA timer is a common time base for all five modules (see Figure 53). The timer
count source is determined from the CPS1 and CPS0 bits in the CMOD SFR (see Table
8) and can be programmed to run at:
1/6 the PCA clock frequency.
1/2 the PCA clock frequency.
the Timer 0 overflow.
the input on the ECI pin (P1.2).
PCA Component
External I/O Pin
16-bit Counter
P1.2/ECI
16-bit Module 0
P1.3/CEX0
16-bit Module 1
P1.4/CEX1
16-bit Module 2
P1.5/CEX2
16-bit Module 3
P1.6/CEX3
16-bit Module 4
P1.7/CEX4
相關(guān)PDF資料
PDF描述
T89C51RD2-DDFI-M 0 to 40MHz Flash Programmable 8-bit Microcontroller
T89C51RD2-DDSC-L 0 to 40MHz Flash Programmable 8-bit Microcontroller
T89C51RD2-DDSC-M 0 to 40MHz Flash Programmable 8-bit Microcontroller
T89C51RD2-DDSI-L 0 to 40MHz Flash Programmable 8-bit Microcontroller
T89C51RD2-DDSI-M 0 to 40MHz Flash Programmable 8-bit Microcontroller
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
T89C51RD2-DDFI-M 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:0 to 40MHz Flash Programmable 8-bit Microcontroller
T89C51RD2-DDRC-L 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:0 to 40MHz Flash Programmable 8-bit Microcontroller
T89C51RD2-DDRC-M 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:0 to 40MHz Flash Programmable 8-bit Microcontroller
T89C51RD2-DDRI-L 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:0 to 40MHz Flash Programmable 8-bit Microcontroller
T89C51RD2-DDRI-M 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:0 to 40MHz Flash Programmable 8-bit Microcontroller