參數(shù)資料
型號: PIC16F819
廠商: Microchip Technology Inc.
英文描述: 18/20-Pin Enhanced FLASH Microcontrollers with nanoWatt Technology(18/20引腳,納瓦技術(shù)增強(qiáng)FLASH微控制器)
中文描述: 18/20-Pin增強(qiáng)型閃存微控制器采用納瓦技術(shù)(18/20引腳,納瓦技術(shù)增強(qiáng)閃存微控制器)
文件頁數(shù): 45/164頁
文件大?。?/td> 3045K
代理商: PIC16F819
2002 Microchip Technology Inc.
Preliminary
DS39598C-page 43
PIC16F818/819
5.2
PORTB and the TRISB Register
PORTB is an 8-bit wide, bi-directional port. The corre-
sponding data direction register is TRISB. Setting a
TRISB bit (= 1) will make the corresponding PORTB
pin an input (i.e., put the corresponding output driver in
a Hi-Impedance mode). Clearing a TRISB bit (= 0) will
make the corresponding PORTB pin an output (i.e., put
the contents of the output latch on the selected pin).
Each of the PORTB pins has a weak internal pull-up. A
single control bit can turn on all the pull-ups. This is per-
formed by clearing bit RBPU (OPTION<7>). The weak
pull-up is automatically turned off when the port pin is
configured as an output. The pull-ups are disabled on a
Power-on Reset.
Four of PORTB’s pins, RB7:RB4, have an interrupt-on-
change feature. Only pins configured as inputs can
cause this interrupt to occur (i.e., any RB7:RB4 pin
configured as an output is excluded from the interrupt-
on-change comparison). The input pins (of RB7:RB4)
are compared with the old value latched on the last
read of PORTB. The “mismatch” outputs of RB7:RB4
are OR’d together to generate the RB Port Change
Interrupt with flag bit RBIF (INTCON<0>).
This interrupt can wake the device from SLEEP. The
user, in the Interrupt Service Routine, can clear the
interrupt in the following manner:
a)
Any read or write of PORTB. This will end the
mismatch condition.
Clear flag bit RBIF.
b)
A mismatch condition will continue to set flag bit RBIF.
Reading PORTB will end the mismatch condition and
allow flag bit RBIF to be cleared.
The interrupt-on-change feature is recommended for
wake-up on key depression operation and operations
where PORTB is only used for the interrupt-on-change
feature. Polling of PORTB is not recommended while
using the interrupt-on-change feature.
RB0/INT is an external interrupt input pin and is
configured using the INTEDG bit (OPTION<6>).
PORTB is multiplexed with several peripheral functions
(see Table 5-3). PORTB pins have Schmitt Trigger
input buffers.
When enabling peripheral functions, care should be
taken in defining TRIS bits for each PORTB pin. Some
peripherals override the TRIS bit to make a pin an out-
put, while other peripherals override the TRIS bit to
make a pin an input. Since the TRIS bit override is in
effect while the peripheral is enabled, read-modify-
write instructions (
BSF, BCF, XORWF
) with TRISB as
destination should be avoided. The user should refer to
the corresponding peripheral section for the correct
TRIS bit settings.
相關(guān)PDF資料
PDF描述
PIC16F83 8-Bit CMOS Flash/EEPROM Microcontollrs(每個I/O口有20mA吸收,25mA驅(qū)動,64字節(jié)數(shù)據(jù)EEPROM,2.0V的微控制器)
PIC16F84 18-pin Flash/EEPROM 8-Bit Microcontrollers
PIC16F85 18/20 Pin, 8-Bit CMOS FLASH Microcontroller with Comparators and A/D Product Brief
PIC16F86 18/20 Pin, 8-Bit CMOS FLASH Microcontroller with Comparators and A/D Product Brief
PIC16F873A 28/40-pin Enhanced FLASH Microcontrollers
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
PIC16F819-E/ML 功能描述:8位微控制器 -MCU 3.5KB 256 RAM 16 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(fēng)格:SMD/SMT
PIC16F819-E/P 功能描述:8位微控制器 -MCU 3.5KB 256 RAM 16 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(fēng)格:SMD/SMT
PIC16F819-E/SO 功能描述:8位微控制器 -MCU 3.5KB 256 RAM 16 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(fēng)格:SMD/SMT
PIC16F819-E/SS 功能描述:8位微控制器 -MCU 3.5KB 256 RAM 16 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(fēng)格:SMD/SMT
PIC16F819-E/SSVAO 制造商:Microchip Technology Inc 功能描述: