参数资料
型号: MC68HC05V7CFNR2
厂商: MOTOROLA INC
元件分类: 微控制器/微处理器
英文描述: 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PQCC68
封装: PLASTIC, LCC-68
文件页数: 6/170页
文件大小: 589K
代理商: MC68HC05V7CFNR2
SECTION 14: SERIAL PERIPHERAL INTERFACE
MOTOROLA
Page 89
MC68HC05V7 Specification Rev. 1.0
WCOL - Write Collision
The write collision bit is set when an attempt is made to write to the serial
peripheral data register while data transfer is taking place. If CPHA is zero, a
transfer is said to begin when SS goes low and the transfer ends when SS goes
high after eight clock cycles on SCK. When CPHA is one, a transfer is said to
begin the first time SCK becomes active while SS is low and the transfer ends
when the SPIF flag gets set. Clearing the WCOL bit is accomplished by reading
the SPSR (with WCOL set) followed by an access to SPDR.
Bit 5 - Not implemented
This bit always reads zero.
MODF - Mode Fault
The mode fault flag indicates that there may have been a multi-master conflict
for system control and allows a proper exit from system operation to a reset or
default system state. The MODF bit is normally clear, and is set only when the
master device has its SS pin pulled low. Setting the MODF bit affects the internal
serial peripheral interface system in the following ways:
SPI interrupt is generated if SPIE=1.
SPE bit is cleared. This disables the SPI.
MSTR bit is cleared, thus forcing the device into the slave mode.
Clearing the MODF bit is accomplished by reading the SPSR (with MODF set),
followed by a write to the SPCR. Control bits SPE and MSTR may be restored
to their original state by user software after the MODF bit has been cleared. It is
also necessary to restore DDRD after a mode fault.
Bits 3-0 - Not Implemented
These bits always read zero.
14.3.3
Serial Peripheral Data I/O Register (SPDR)
The serial peripheral data I/O register is used to transmit and receive data on the serial bus.
Only a write to this register will initiate transmission/reception of another byte, and this will
only occur in the master device. At the completion of transmitting a byte of data, the SPIF
status bit is set in both the master and slave devices.
When the user reads the serial peripheral data I/O register, a buffer is actually being read.
The first SPIF must be cleared by the time a second transfer of the data from the shift
register to the read buffer is initiated, or an overrun condition will exist. In cases of overrun,
the byte that causes the overrun is lost.
A write to the serial peripheral data I/O register is not buffered and places data directly into
the shift register for transmission.
SPD7
SPD5
SPD4
SPD3
SPD2
PSD1
SPD0
SPD6
$0C
-
------
-
RESET:
相关PDF资料
PDF描述
MC68HC05V7FNR2 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PQCC68
MC68HC05V7FN 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PQCC68
MC68HC05V7CB 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDIP56
MC68HC05V7CFU 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PQFP64
MC68HC05X16FU 8-BIT, MROM, MICROCONTROLLER, PQFP64
相关代理商/技术参数
参数描述
MC68HC05X16 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:High-density complementary metal oxide semiconductor HCMOS) microcontroller unit
MC68HC05X32 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:High-density complementary metal oxide semiconductor HCMOS) microcontroller unit
MC68HC05X4 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05X4CDW 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05X4DW 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit