参数资料
型号: MCP2515DM-PCTL
厂商: Microchip Technology
文件页数: 7/92页
文件大小: 0K
描述: BOARD DEMO FOR MCP2515
标准包装: 1
系列: PICtail™
主要目的: 接口,CAN 控制器
嵌入式: 是,MCU,8 位
已用 IC / 零件: MCP2515,MCP25020
主要属性: 带 CAN 输入/输出扩展器的独立 CAN 控制器
已供物品: 板,缆线,CD
产品目录页面: 685 (CN2011-ZH PDF)
相关产品: MCP2515T-I/ST-ND - IC CAN CONTROLLER W/SPI 20TSSOP
MCP2515T-I/SO-ND - IC CAN CONTROLLER W/SPI 18SOIC
MCP2515T-E/ST-ND - IC CAN CONTROLLER W/SPI 20TSSOP
MCP2515T-E/SO-ND - IC CAN CONTROLLER W/SPI 18SOIC
MCP2515-E/ST-ND - IC CAN CONTROLLER W/SPI 20TSSOP
MCP2515-E/SO-ND - IC CAN CONTROLLER W/SPI 18SOIC
MCP2515-E/P-ND - IC CAN CONTROLLER W/SPI 18DIP
MCP2515-I/ST-ND - IC CAN CONTROLLER W/SPI 20TSSOP
MCP2515-I/SO-ND - IC CAN CONTROLLER W/SPI 18SOIC
MCP2515-I/P-ND - IC CAN CONTROLLER W/SPI 18DIP
更多...
MCP2515
2.0
CAN MESSAGE FRAMES
CAN frame will win arbitration due to the assertion of a
dominant lDE bit. Also, the SRR bit in an extended
The MCP2515 supports standard data frames,
extended data frames and remote frames (standard
and extended), as defined in the CAN 2.0B
specification.
CAN frame must be recessive to allow the assertion of
a dominant RTR bit by a node that is sending a
standard CAN remote frame.
The SRR and lDE bits are followed by the remaining
2.1
Standard Data Frame
18 bits of the identifier (Extended lD) and the remote
transmission request bit.
The CAN standard data frame is shown in Figure 2-1.
As with all other frames, the frame begins with a Start-
Of-Frame (SOF) bit, which is of the dominant state and
allows hard synchronization of all nodes.
The SOF is followed by the arbitration field, consisting
of 12 bits: the 11-bit identifier and the Remote
Transmission Request (RTR) bit. The RTR bit is used
to distinguish a data frame (RTR bit dominant) from a
remote frame (RTR bit recessive).
Following the arbitration field is the control field,
consisting of six bits. The first bit of this field is the
Identifier Extension (IDE) bit, which must be dominant
to specify a standard frame. The following bit, Reserved
Bit Zero (RB0), is reserved and is defined as a dominant
bit by the CAN protocol. The remaining four bits of the
control field are the Data Length Code (DLC), which
specifies the number of bytes of data (0-8 bytes)
To enable standard and extended frames to be sent
across a shared network, the 29-bit extended message
identifier is split into 11-bit (Most Significant) and 18-bit
(Least Significant) sections. This split ensures that the
lDE bit can remain at the same bit position in both the
standard and extended frames.
Following the arbitration field is the six-bit control field.
The first two bits of this field are reserved and must be
dominant. The remaining four bits of the control field
are the DLC, which specifies the number of data bytes
contained in the message.
The remaining portion of the frame (data field, CRC
field, acknowledge field, end-of-frame and
intermission) is constructed in the same way as a
standard data frame (see Section 2.1 “Standard Data
contained in the message.
2.3
Remote Frame
After the control field, is the data field, which contains
any data bytes that are being sent, and is of the length
defined by the DLC (0-8 bytes).
The Cyclic Redundancy Check (CRC) field follows the
data field and is used to detect transmission errors. The
CRC field consists of a 15-bit CRC sequence, followed
by the recessive CRC Delimiter bit.
The final field is the two-bit Acknowledge (ACK) field.
During the ACK Slot bit, the transmitting node sends
out a recessive bit. Any node that has received an
error-free frame acknowledges the correct reception of
the frame by sending back a dominant bit (regardless
of whether the node is configured to accept that
specific message or not). The recessive acknowledge
delimiter completes the acknowledge field and may not
be overwritten by a dominant bit.
Normally, data transmission is performed on an
autonomous basis by the data source node (e.g., a
sensor sending out a data frame). It is possible,
however, for a destination node to request data from
the source. To accomplish this, the destination node
sends a remote frame with an identifier that matches
the identifier of the required data frame. The
appropriate data source node will then send a data
frame in response to the remote frame request.
There are two differences between a remote frame
(shown in Figure 2-3 ) and a data frame. First, the RTR
bit is at the recessive state and, second, there is no
data field. In the event of a data frame and a remote
frame with the same identifier being transmitted at the
same time, the data frame wins arbitration due to the
dominant RTR bit following the identifier. In this way,
the node that transmitted the remote frame receives
2.2
Extended Data Frame
the desired data immediately.
In the extended CAN data frame, shown in Figure 2-2 ,
the SOF bit is followed by the arbitration field, which
2.4
Error Frame
consists of 32 bits. The first 11 bits are the Most
Significant bits (MSb) (Base-lD) of the 29-bit identifier.
These 11 bits are followed by the Substitute Remote
Request (SRR) bit, which is defined to be recessive.
The SRR bit is followed by the lDE bit, which is
recessive to denote an extended CAN frame.
It should be noted that if arbitration remains unresolved
after transmission of the first 11 bits of the identifier, and
one of the nodes involved in the arbitration is sending
a standard CAN frame (11-bit identifier), the standard
? 2003-2012 Microchip Technology Inc.
An error frame is generated by any node that detects a
bus error. An error frame, shown in Figure 2-4 , consists
of two fields: an error flag field followed by an error
delimiter field. There are two types of error flag fields.
The type of error flag field sent depends upon the error
status of the node that detects and generates the error
flag field.
DS21801G-page 7
相关PDF资料
PDF描述
GBM10DRMD-S664 CONN EDGECARD 20POS .156 WW
VI-BWP-EW CONVERTER MOD DC/DC 13.8V 100W
ELC-10D220E COIL CHOKE 22UH RADIAL
A2MXS-6006M ADM60S/AE60M/X
A3AAH-2018G IDC CABLE - ASC20H/AE20G/ASC20H
相关代理商/技术参数
参数描述
MCP2515DM-PTPLS 功能描述:子卡和OEM板 MCP2515 PICTail Plus Daughtr Brd RoHS:否 制造商:BeagleBoard by CircuitCo 产品:BeagleBone LCD4 Boards 用于:BeagleBone - BB-Bone - Open Source Development Kit
MCP2515-E 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:Stand-Alone CAN Controller with SPI Interface
MCP2515-E/ML 制造商:Microchip Technology Inc 功能描述:
MCP2515-E/P 功能描述:网络控制器与处理器 IC W/ SPI Inter 125dC RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流(最大值):595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray
MCP2515-E/SO 功能描述:网络控制器与处理器 IC W/ SPI Inter 125dC RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流(最大值):595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray