EtherCAT主站SOEM函数详解----SDO读写函数

ethercatcoe.h头文件SDO读写函数SDO读取函数SDO写函数

获取SOEM主站或了解文件分布，可以读取我以前写的博客SOEM主站软件包及函数头文件介绍,本篇ethercatcoe文件相关的函数，COE的全称是CanOpen over EtherCAT, 采用CanOpen的相关协议开发了EtherCAT的运用层，核心是对象字典，想了解PDO相关知识，可以读CanOpen通信----PDO与SDO。对于报文结构体相关知识，可以参照EtherCAT数据帧及SOEM报文数据结构介绍,对下文的理解有一定帮组。

ethercatcoe.h头文件

为了比较全面的了解COE, 本文将先给出ethercatcoe.h的头文件，如下所示，其中核心的是读写函数。

/* * Licensed under the GNU General Public License version 2 with exceptions. See * LICENSE file in the project root for full license information */ /** \file * \brief * Headerfile for ethercatcoe.c */ #ifndef _ethercatcoe_ #define _ethercatcoe_ #ifdef __cplusplus extern "C" { #endif /** max entries in Object Description list */ #define EC_MAXODLIST 1024 /** max entries in Object Entry list */ #define EC_MAXOELIST 256 /* Storage for object description list */ typedef struct { /** slave number */ uint16 Slave; /** number of entries in list */ uint16 Entries; /** array of indexes */ uint16 Index[EC_MAXODLIST]; /** array of datatypes, see EtherCAT specification */ uint16 DataType[EC_MAXODLIST]; /** array of object codes, see EtherCAT specification */ uint8 ObjectCode[EC_MAXODLIST]; /** number of subindexes for each index */ uint8 MaxSub[EC_MAXODLIST]; /** textual description of each index */ char Name[EC_MAXODLIST][EC_MAXNAME+1]; } ec_ODlistt; /* storage for object list entry information */ typedef struct { /** number of entries in list */ uint16 Entries; /** array of value infos, see EtherCAT specification */ uint8 ValueInfo[EC_MAXOELIST]; /** array of value infos, see EtherCAT specification */ uint16 DataType[EC_MAXOELIST]; /** array of bit lengths, see EtherCAT specification */ uint16 BitLength[EC_MAXOELIST]; /** array of object access bits, see EtherCAT specification */ uint16 ObjAccess[EC_MAXOELIST]; /** textual description of each index */ char Name[EC_MAXOELIST][EC_MAXNAME+1]; } ec_OElistt; #ifdef EC_VER1 void ec_SDOerror(uint16 Slave, uint16 Index, uint8 SubIdx, int32 AbortCode); int ec_SDOread(uint16 slave, uint16 index, uint8 subindex, boolean CA, int *psize, void *p, int timeout); int ec_SDOwrite(uint16 Slave, uint16 Index, uint8 SubIndex, boolean CA, int psize, void *p, int Timeout); int ec_RxPDO(uint16 Slave, uint16 RxPDOnumber , int psize, void *p); int ec_TxPDO(uint16 slave, uint16 TxPDOnumber , int *psize, void *p, int timeout); int ec_readPDOmap(uint16 Slave, int *Osize, int *Isize); int ec_readPDOmapCA(uint16 Slave, int Thread_n, int *Osize, int *Isize); int ec_readODlist(uint16 Slave, ec_ODlistt *pODlist); int ec_readODdescription(uint16 Item, ec_ODlistt *pODlist); int ec_readOEsingle(uint16 Item, uint8 SubI, ec_ODlistt *pODlist, ec_OElistt *pOElist); int ec_readOE(uint16 Item, ec_ODlistt *pODlist, ec_OElistt *pOElist); #endif void ecx_SDOerror(ecx_contextt *context, uint16 Slave, uint16 Index, uint8 SubIdx, int32 AbortCode); int ecx_SDOread(ecx_contextt *context, uint16 slave, uint16 index, uint8 subindex, boolean CA, int *psize, void *p, int timeout); int ecx_SDOwrite(ecx_contextt *context, uint16 Slave, uint16 Index, uint8 SubIndex, boolean CA, int psize, void *p, int Timeout); int ecx_RxPDO(ecx_contextt *context, uint16 Slave, uint16 RxPDOnumber , int psize, void *p); int ecx_TxPDO(ecx_contextt *context, uint16 slave, uint16 TxPDOnumber , int *psize, void *p, int timeout); int ecx_readPDOmap(ecx_contextt *context, uint16 Slave, int *Osize, int *Isize); int ecx_readPDOmapCA(ecx_contextt *context, uint16 Slave, int Thread_n, int *Osize, int *Isize); int ecx_readODlist(ecx_contextt *context, uint16 Slave, ec_ODlistt *pODlist); int ecx_readODdescription(ecx_contextt *context, uint16 Item, ec_ODlistt *pODlist); int ecx_readOEsingle(ecx_contextt *context, uint16 Item, uint8 SubI, ec_ODlistt *pODlist, ec_OElistt *pOElist); int ecx_readOE(ecx_contextt *context, uint16 Item, ec_ODlistt *pODlist, ec_OElistt *pOElist); #ifdef __cplusplus } #endif #endif

SDO读写函数

SDO服务数据，也称为邮箱数据，通常用在驱动器配置阶段，其数据传输是非周期性的。

SDO读取函数

int ecx_SDOread(ecx_contextt *context, uint16 slave, uint16 index, uint8 subindex, boolean CA, int *psize, void *p, int timeout); /** CoE SDO read, blocking. Single subindex or Complete Access. * * Only a "normal" upload request is issued. If the requested parameter is <= 4bytes * then a "expedited" response is returned, otherwise a "normal" response. If a "normal" * response is larger than the mailbox size then the response is segmented. The function * will combine all segments and copy them to the parameter buffer. * * @param[in] context = context struct * @param[in] slave = Slave number * @param[in] index = Index to read * @param[in] subindex = Subindex to read, must be 0 or 1 if CA is used. * @param[in] CA = FALSE = single subindex. TRUE = Complete Access, all subindexes read. * @param[in,out] psize = Size in bytes of parameter buffer, returns bytes read from SDO. * @param[out] p = Pointer to parameter buffer * @param[in] timeout = Timeout in us, standard is EC_TIMEOUTRXM * @return Workcounter from last slave response */

参数解释：

ecx_contextt *context：报文结构体指针，所有信息都是通过报文传递的，报文中包含了一系列配置信息；uint16 slave ：从站编号，有顺序寻址、逻辑寻址等，采用顺序寻址在驱动器配置过程自动扫描分配，与连接顺序有关；uint16 index：对象字典索引，CanOpen相关协议uint8 subindex：对象字典子索引，CanOpen相关协议boolean CA：完全访问（Complete Access），会访问所有子索引，一般填写False,仅访问给定子索引。int *psize： 读取参数字节数void *p：读取参数指针，通过该指针可获取想要的信息int timeout：读取最大超时，单位us（微秒），一般给EC_TIMEOUTRXM，其值为700000@return Workcounter：返回计数wck,用于对比是否正确处理报文。

SDO写函数

int ecx_SDOwrite(ecx_contextt *context, uint16 Slave, uint16 Index, uint8 SubIndex, boolean CA, int psize, void *p, int Timeout); /** CoE SDO write, blocking. Single subindex or Complete Access. * * A "normal" download request is issued, unless we have * small data, then a "expedited" transfer is used. If the parameter is larger than * the mailbox size then the download is segmented. The function will split the * parameter data in segments and send them to the slave one by one. * * @param[in] context = context struct * @param[in] Slave = Slave number * @param[in] Index = Index to write * @param[in] SubIndex = Subindex to write, must be 0 or 1 if CA is used. * @param[in] CA = FALSE = single subindex. TRUE = Complete Access, all subindexes written. * @param[in] psize = Size in bytes of parameter buffer. * @param[out] p = Pointer to parameter buffer * @param[in] Timeout = Timeout in us, standard is EC_TIMEOUTRXM * @return Workcounter from last slave response

参数解释：

ecx_contextt *context：报文结构体指针，所有信息都是通过报文传递的，报文中包含了一系列配置信息；uint16 slave ：从站编号，有顺序寻址、逻辑寻址等，采用顺序寻址在驱动器配置过程自动扫描分配，与连接顺序有关；uint16 index：对象字典索引，CanOpen相关协议uint8 subindex：对象字典子索引，CanOpen相关协议boolean CA：完全访问（Complete Access），会访问所有子索引，一般填写False,仅访问给定子索引。int psize： 需要写入参数字节数void *p：写入参数指针，通过该指针可获修改对应从站数据int timeout：写入最大超时，单位us（微秒），一般给EC_TIMEOUTRXM，其值为700000@return Workcounter：返回计数wck,用于对比是否正确处理报文。