參數(shù)資料
型號: MC68HC05K0CDW
廠商: FREESCALE SEMICONDUCTOR INC
元件分類: 微控制器/微處理器
英文描述: 8-BIT, MROM, 2 MHz, MICROCONTROLLER, PDSO16
封裝: SOIC-16
文件頁數(shù): 126/154頁
文件大?。?/td> 1585K
代理商: MC68HC05K0CDW
Parallel Input/Output (I/O)
Port B
MC68HC05K0 MC68HC05K1 — Rev. 2.0
Technical Data
Parallel Input/Output (I/O)
7.4.3 Pulldown Register B
Port B pins have mask-optional pulldown devices that sink
approximately 100
A. Clearing the PDIB1 and PDIB0 bits in pulldown
register B turns on the port B pulldown devices. Pulldown register B can
turn on a port B pulldown device only when the port B pin is an input. See
If the pulldown mask option is selected, reset initializes all port A and
port B pins as inputs with pulldown devices turned on.
PDIB1 and PDIB0 — Port B Pulldown Inhibit Bits 1 and 0
Writing logic 0s to these write-only bits turns on the port B pulldown
devices. Reading pulldown register B returns undefined data. Reset
clears PDIB1 and PDIB0.
1 = Corresponding port B pin pulldown device turned off
0 = Corresponding port B pin pulldown device turned on
Bits 7–2 — Not used
Bits 7–2 always read as logic 0s.
NOTE:
To avoid excessive current draw, connect all unused input pins to VDD
or VSS. Or change I/O pins to outputs by writing to DDRB in user
initialization code. Avoid a floating port B input by clearing its pulldown
register bit before changing its DDRB bit from logic 1 to logic 0.
Because pulldown register B is a write-only register, using the
read-modify-write instruction may result in inadvertently turning bits on
or off.
Address:
$0011
Bit 7
654321
Bit 0
Read:
Write:
PDIB1
PDIB0
Reset:
UUUUUU
0
= Unimplemented
U = Unaffected
Figure 7-7. Pulldown Register B (PDRB)
F
re
e
sc
a
le
S
e
m
ic
o
n
d
u
c
to
r,
I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
n
c
..
.
相關PDF資料
PDF描述
MC68HC05K0P 8-BIT, MROM, 2 MHz, MICROCONTROLLER, PDIP16
MC68HC05K1VDW 8-BIT, MROM, 2 MHz, MICROCONTROLLER, PDSO16
MC68HC05K1DW 8-BIT, MROM, 2 MHz, MICROCONTROLLER, PDSO16
MC68HC05K1CDW 8-BIT, MROM, 2 MHz, MICROCONTROLLER, PDSO16
MC68HC05K3CDW 8-BIT, MROM, 2 MHz, MICROCONTROLLER, PDSO16
相關代理商/技術參數(shù)
參數(shù)描述
MC68HC05K1 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05K1CDW 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05K1CP 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05K1DW 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05K1P 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit