參數(shù)資料
型號: PIC16C71-20I/P
廠商: Microchip Technology
文件頁數(shù): 174/177頁
文件大小: 0K
描述: IC MCU OTP 1KX14 A/D 18DIP
產(chǎn)品培訓模塊: Asynchronous Stimulus
8-bit PIC® Microcontroller Portfolio
標準包裝: 25
系列: PIC® 16C
核心處理器: PIC
芯體尺寸: 8-位
速度: 20MHz
外圍設備: POR,WDT
輸入/輸出數(shù): 13
程序存儲器容量: 1.75KB(1K x 14)
程序存儲器類型: OTP
RAM 容量: 36 x 8
電壓 - 電源 (Vcc/Vdd): 4 V ~ 6 V
數(shù)據(jù)轉(zhuǎn)換器: A/D 4x8b
振蕩器型: 外部
工作溫度: -40°C ~ 85°C
封裝/外殼: 18-DIP(0.300",7.62mm)
包裝: 管件
配用: 309-1059-ND - ADAPTER 18 ZIF BD W/18SO PLUGS
DVA16XP180-ND - ADAPTER DEVICE FOR MPLAB-ICE
AC164010-ND - MODULE SKT PROMATEII DIP/SOIC
96
7593L–AVR–09/12
AT90USB64/128
13. Timer/Counter0, Timer/Counter1, and Timer/Counter3 prescalers
Timer/Counter0, 1, and 3 share the same prescaler module, but the Timer/Counters can have
different prescaler settings. The description below applies to all Timer/Counters. Tn is used as a
general name, n = 0, 1 or 3.
13.1
Internal clock source
The Timer/Counter can be clocked directly by the system clock (by setting the CSn2:0 = 1). This
provides the fastest operation, with a maximum Timer/Counter clock frequency equal to system
clock frequency (f
CLK_I/O). Alternatively, one of four taps from the prescaler can be used as a
clock source. The prescaled clock has a frequency of either f
CLK_I/O/8, fCLK_I/O/64, fCLK_I/O/256, or
f
CLK_I/O/1024.
13.2
Prescaler reset
The prescaler is free running, that is, operates independently of the Clock Select logic of the
Timer/Counter, and it is shared by the Timer/Counter Tn. Since the prescaler is not affected by
the Timer/Counter’s clock select, the state of the prescaler will have implications for situations
where a prescaled clock is used. One example of prescaling artefacts occurs when the timer is
enabled and clocked by the prescaler (6 > CSn2:0 > 1). The number of system clock cycles from
when the timer is enabled to the first count occurs can be from 1 to N+1 system clock cycles,
where N equals the prescaler divisor (8, 64, 256, or 1024).
It is possible to use the prescaler reset for synchronizing the Timer/Counter to program execu-
tion. However, care must be taken if the other Timer/Counter that shares the same prescaler
also uses prescaling. A prescaler reset will affect the prescaler period for all Timer/Counters it is
connected to.
13.3
External clock source
An external clock source applied to the Tn pin can be used as Timer/Counter clock (clk
Tn). The
Tn pin is sampled once every system clock cycle by the pin synchronization logic. The synchro-
nized (sampled) signal is then passed through the edge detector. Figure 13-1 shows a functional
equivalent block diagram of the Tn synchronization and edge detector logic. The registers are
clocked at the positive edge of the internal system clock (clk
I/O). The latch is transparent in the
high period of the internal system clock.
The edge detector generates one clk
Tn pulse for each positive (CSn2:0 = 7) or negative (CSn2:0
= 6) edge it detects.
Figure 13-1. Tn/T0 pin sampling.
The synchronization and edge detector logic introduces a delay of 2.5 to 3.5 system clock cycles
from an edge has been applied to the Tn pin to the counter is updated.
Enabling and disabling of the clock input must be done when Tn has been stable for at least one
system clock cycle, otherwise it is a risk that a false Timer/Counter clock pulse is generated.
Tn_sync
(To clock
select logic)
Edge detector
Synchronization
DQ
LE
DQ
Tn
clk
I/O
相關PDF資料
PDF描述
PIC18LF4510-I/P IC MCU FLASH 16KX16 40DIP
PIC18F2515-I/SO IC MCU FLASH 24KX16 28SOIC
DSPIC33FJ128GP202-I/SP IC DSPIC MCU/DSP 128K 28DIP
PIC24FJ128GA310-I/BG MCU 16BIT 128KB FLASH 121TFBGA
PIC24HJ128GP204-I/PT IC PIC MCU FLASH 128K 44TQFP
相關代理商/技術(shù)參數(shù)
參數(shù)描述
PIC16C712-20/P 功能描述:8位微控制器 -MCU 1.75KB OTP 128RAM 13 I/O 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 最大時鐘頻率:50 MHz 程序存儲器大小: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 安裝風格:SMD/SMT
PIC16C712-20/SO 功能描述:8位微控制器 -MCU 1.75KB 128RAM 13 I/O 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 最大時鐘頻率:50 MHz 程序存儲器大小: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 安裝風格:SMD/SMT
PIC16C712-20/SS 功能描述:8位微控制器 -MCU 1.75KB 128RAM 13 I/O 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 最大時鐘頻率:50 MHz 程序存儲器大小: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 安裝風格:SMD/SMT
PIC16C712-20E 制造商:Microchip Technology Inc 功能描述:
PIC16C712-20E/P 功能描述:8位微控制器 -MCU 1.75KB 128RAM 13 I/O 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 最大時鐘頻率:50 MHz 程序存儲器大小: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 安裝風格:SMD/SMT