参数资料
型号: MC68HC05C8AP
厂商: FREESCALE SEMICONDUCTOR INC
元件分类: 微控制器/微处理器
英文描述: 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDIP40
封装: PLASTIC, DIP-40
文件页数: 49/116页
文件大小: 781K
代理商: MC68HC05C8AP
Input/Output (I/O) Ports
MC68HC05C8A MC68HCL05C8A MC68HSC05C8A Data Sheet, Rev. 5.1
38
Freescale Semiconductor
7.4 Port C
Port C is an 8-bit bidirectional port. The port C data register is at $0002 and the data direction register
(DDR) is at $0006. Reset does not affect the data registers, but clears the data direction registers, thereby
returning the ports to inputs. Writing a 1 to a DDR bit sets the corresponding port bit to output mode. PC7
has a high current sink and source capability.
7.5 Port D
Port D is a 7-bit fixed input port. Four of its pins are shared with the SPI subsystem, two more are shared
with the SCI subsystem. Reset does not affect the data registers. During reset, all seven bits become valid
input ports because all special function output drivers associated with the SCI, timer, and SPI subsystems
are disabled.
7.6 Input/Output Programming
I/O port pins may be programmed as inputs or outputs under software control. The direction of the pins is
determined by the state of the corresponding bit in the port data direction register (DDR). Each I/O port
has an associated DDR. Any I/O port pin is configured as an output if its corresponding DDR bit is set to
a logic 1. A pin is configured as an input if its corresponding DDR bit is cleared to a logic 0.
At power-on or reset, all DDRs are cleared, which configures all I/O pins as inputs. The data direction
registers are capable of being written to or read by the processor. During the programmed output state,
a read of the data register actually reads the value of the output data latch and not the I/O pin. For further
information, refer to Table 7-1 and Figure 7-2.
Table 7-1. I/O Pin Functions
R/W(1)
1. R/W is an internal signal.
DDR
I/O Pin Function
0
The I/O pin is in input mode. Data is written into the output data latch.
0
1
Data is written into the output data latch and output to the I/O pin.
1
0
The state of the I/O pin is read.
1
The I/O pin is in an output mode. The output data latch is read.
相关PDF资料
PDF描述
MC68HC705B16NMFN 8-BIT, OTPROM, 2.1 MHz, MICROCONTROLLER, PQCC52
MC68HC908GZ60VFJ 8-BIT, FLASH, 8 MHz, MICROCONTROLLER, PQFP32
MC68HLC908JK3CP 8-BIT, FLASH, 4 MHz, MICROCONTROLLER, PDIP20
MC908MR8CDWR2 8-BIT, FLASH, 8.2 MHz, MICROCONTROLLER, PDSO28
MC9S12DG128CPV 16-BIT, FLASH, 25 MHz, MICROCONTROLLER, PQFP112
相关代理商/技术参数
参数描述
MC68HC05C9 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:TECHNICAL DATA
MC68HC05C9A 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:Microcontrollers
MC68HC05C9AB 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:Microcontrollers
MC68HC05C9AFB 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:Microcontrollers
MC68HC05C9AFN 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:Microcontrollers