LINUXCNC源程序原理说明.doc

''opLINUXCNC 源程序学习源程序的树结构如下： Overview of the emc2 directory (generated by tree -I .git -d) :. |- app-defaults |- bin (user mode binaries) |- configs | |- 5axis | |- boss | |- common | |- dallur-thc | |- demo_mazak (sample mazak config files) | |- demo_sim_cl (sample sim with ladder IO) | |- demo_step_cl (sample stepper with ladder IO) | |- etch-servo | |- halui_halvcp | |- hexapod-sim | |- lathe-pluto | |- m5i20 (sample servo using Mesa PCI) | |- max | |- motenc (sample servo using Vital PCI) | |- nist-lathe | |- plasma-thc | |- plasma-thc-sim | |- ppmc | |- puma | |- scara | |- sim (simulated motion and IO) | |- stepper (parport stepper driver) | |- stepper-gantry | |- stepper-xyza | |- stg (sample servo using STG ISA) | |- univpwm (sample PICO servo generator) | |- univstep (sample PICO stepper generator) | - vti |- debian (files needed to build deb packages) | |- extras-Ubuntu-5.10 (extra files for Ubuntu 5.10) | | |- etc | | | |- modprobe.d | | | |- udev | | | | |- rules.d | | | | - scripts | | | - xdg | | | - menus'' | | | - applications-merged | | - usr | | - share | | |- applications | | |- desktop-directories | | - pixmaps | |- extras-Ubuntu-6.06 (extra files for building on Ubuntu 6.06 Dapper Drake) | | |- etc | | | |- modprobe.d | | | |- udev | | | | |- rules.d | | | | - scripts | | | - xdg | | | - menus | | | - applications-merged | | - usr | | - share | | |- applications | | |- desktop-directories | | - pixmaps | |- extras-Ubuntu-7.10 (extra files for building on Ubuntu 7.10) | | |- etc | | | |- modprobe.d | | | |- udev | | | | - rules.d | | | - xdg | | | - menus | | | - applications-merged | | - usr | | - share | | |- applications | | |- desktop-directories | | - pixmaps | |- extras-Ubuntu-8.04 (extra files for building on Ubuntu 8.04 Hardy Heron) | | |- etc | | | |- modprobe.d | | | - xdg | | | - menus | | | - applications-merged | | - usr | | - share | | |- applications | | |- desktop-directories | | - pixmaps | |- extras-sim-Ubuntu-5.10 (extra files for sim package for Ubuntu 5.10) | | |- etc'' | | | - xdg | | | - menus | | | - applications-merged | | - usr | | - share | | |- applications | | |- desktop-directories | | - pixmaps | - extras-sim-Ubuntu-6.06 (extra files for sim package for Ubuntu 6.06 Dapper Drake) | |- etc | | - xdg | | - menus | | - applications-merged | - usr | - share | |- applications | |- desktop-directories | - pixmaps |- docs (All the important and relevant Docs.) | |- help | |- html (html version of docs - some generated from lyx) | |- man (man pages) | | |- man1 | | |- man3 | | - man9 | - src (API and source notes should be in each src dir.) (source for the handbooks) (top level .lyx files) | |- code | |- common (shared .lyx files and images, such as glossary, GPLD license) | |- config | |- gcode (.lyx files, images, etc. for G-Code documentation) | |- gui (.lyx files, images, etc. for GUI documentation) | |- hal (.lyx files, images, etc. for HAL documentation) | |- install | |- ladder | |- motion | - quickstart |- include (headers installed here - originals in src/xxx/) |- lib (user mode object files) | - python | |- rs274 | - yapps |- nc_files (Sample NC files) |- rtlib (kernel mode object files, only after a successfull compile) |- scripts(bash scripts like linuxcnc, realtime, rip-environment, etc.) |- share | |- axis'' | | |- images | | - tcl | |- emc | - locale | |- de | | - LC_MESSAGES | |- es | | - LC_MESSAGES | |- fr | | - LC_MESSAGES | |- hu | | - LC_MESSAGES | |- it | | - LC_MESSAGES | |- pt_BR | | - LC_MESSAGES | |- ro | | - LC_MESSAGES | |- ru | | - LC_MESSAGES | |- se | | - LC_MESSAGES | |- sr | | - LC_MESSAGES | - zh_CN | - LC_MESSAGES |- src (source tree - configure script, top level makefile, Makefile.inc, etc) | | | |- depends (generated dependency tree) | | | |- emc (actual LinuxCNC code) | | |- canterp (interpreter for canonical commands) | | |- ini (inifile related operations) | | |- iotask (IO interface, lots of HAL pins) | | |- kinematics (trajectory planner and kinematics) | | |- motion (motion controller, talks through SHM to the rest of EMC) | | |- nml_intf (emc specific NML implementation, all messages sent in emc) | | |- rs274ngc (the rs274 g-code interpreter) | | |- sai | | |- task (core component in emc, dispatches actions to other parts) | | - usr_intf (interfaces for some GUIs, and other interfaces: AXIS, halui, stepconf) | | |- axis | | | |- etc | | | |- extensions | | | - scripts | | - stepconf'' | |- hal (the Hardware Abstraction Layer, provides a unified interface across all hardware) | | |- classicladder | | | - projects_examples | | |- components | | |- drivers | | | |- m5i20 | | | | |- bit | | | | - hostmot5_src | | | |- mesa-hostmot2 | | | | |- doc | | | | - firmware | | | | |- 5i20 | | | | | - SOURCE | | | | - 7i43 | | | | |- CPLD | | | | | - SOURCE | | | | - SOURCE | | | |- mesa7i43-firmware | | | | |- gpio | | | | | - source | | | | |- hostmot2 | | | | | - src | | | | - source | | | |- mesa_5i2x | | | | - firmware | | | |- pluto_servo_firmware | | | - pluto_step_firmware | | |- user_comps | | | |- devices | | | - vcp | | - utils | | - halgui | |- libnml (a clean implementation of RCSLIB) | | |- buffer | | |- cms | | |- inifile | | |- linklist | | |- nml | | |- os_intf | | |- posemath | | - rcs | |- module_helper | |- objects | | |- emc | | | |- canterp | | | |- ini'' | | | |- iotask | | | |- motion | | | |- nml_intf | | | |- rs274ngc | | | |- sai | | | |- task | | | - usr_intf | | | - axis | | | - extensions | | |- hal | | | |- classicladder | | | |- components | | | |- drivers | | | |- user_comps | | | | |- devices | | | | - vcp | | | - utils | | |- libnml | | | |- buffer | | | |- cms | | | |- inifile | | | |- linklist | | | |- nml | | | |- os_intf | | | |- posemath | | | - rcs | | |- rtapi | | |- rtemc | | | |- kinematics | | | - motion | | |- rthal | | | |- classicladder | | | |- components | | | - utils | | |- rtlibnml | | | - posemath | | - rtobjects | | - hal | | - components | |- po (Translation files for i18n support) | |- rtapi (*.c and *.h for RTAPI) (unified RT API, wraps over RTLinux, RTAI and sim) | | - examples (testing examples for the RTAPI) | | |- extint | | |- fifo | | |- semaphore | | |- shmem'' | | - timer | - tests |- tcl (tkemc.tcl, mini.tcl - the tcl GUI's) | |- bin | - scripts - tests|- abs.0|- and-or-not-mux.0|- basic|- ccomp| |- lathe-comp| |- mill-g90g91g92| |- mill-line-arc-entry| - mill-zchanges|- counter-encoder.0|- flipflop.0|- interp| |- cam-nisley| - flowsnake|- limit3.0|- limit3.1|- limit3.2|- modparam.0|- overrun|- oword| - sub.0|- save.0|- save.1|- source.0|- stepgen.0|- stepgen.1|- stepgen.2|- threads.0- timedelay.0Overview of the emc2 install dirs:/ (file system root)|- etc/| | - init.d/| | - realtime (realtime start/stop script)''|- $(prefix) (default: /usr/local)| | (all the following $xxxxdir are configurable through autoconf | | |- bin/ (known as $bindir, files from EMC2/bin)| | |- sbin/ (known as $sbindir, )| | |- etc/ (known as $sysconfdir, config files and subdirs from configs/)| | |- lib/ (known as $libdir, lib files *.so from libs/)| | - share/| | - emc/| | | |- docs/| | | | - (All the important and relevant Docs.)| | |- handbooks/| | | | - (PDF versions of handbooks)| | - nc_files/| | - (Sample NC files)|- $MAN_DIR/ (default: /usr/local/man)| | |- man1/| | | | | | - man3/| | | - $moduledir/ (based on where ./configure finds the RTOS modules)根据这个结构树，我们可以清楚的知道每一个文件夹，每一个子文件的作用，包括了接口，硬件抽象层，实 时内核等等部分。当然，在这里面我们需要深入研究的是 linuxcnc-dev/src/emc 文件夹中的各个文件，也是该 数控系统的核心所在。我们再次列出 linuxcnc-dev/src/emc 中的子结构树：''linuxcnc-dev/src/emc 中的子结构树：| |- emc (actual LinuxCNC code) | | |- canterp (interpreter for canonical commands) | | |- ini (inifile related operations) | | |- iotask (IO interface, lots of HAL pins) | | |- kinematics (trajectory planner and kinematics) | | |- motion (motion controller, talks through SHM to the rest of EMC) | | |- nml_intf (emc specific NML implementation, all messages sent in emc) | | |- rs274ngc (the rs274 g-code interpreter) | | |- sai | | |- task (core component in emc, dispatches actions to other parts) | | - usr_intf (interfaces for some GUIs, and other interfaces: AXIS, halui, stepconf) | | |- axis | | | |- etc | | | |- extensions | | | - scripts | | - stepconf根据该结构树，我们一个一个的再一次进行分析： （1）canterp (interpreter for canonical commands，即规范命令的解释器) #include / FILE, fopen(), fclose() #include / strcpy() #include / isspace() #include #include #include “config.h“ #include “emc/nml_intf/interp_return.hh“ #include “emc/nml_intf/canon.hh“ #include “emc/rs274ngc/interp_base.hh“ 其中包括了语法解析，读取，执行等函数，对刀具信息、主轴转速、开始、停止等信息进行判断和执行工作。（2）ini (inifile related operations，初始化相关的文件)同样，列出该文件夹的结构树： | |- ini (inifile related operations) | | |- emcIniFile.cc/hh | | |- iniaxis.cc/hh | | |- inihal.cc/hh | | |- initraj.cc/hh | | |- initool.cc /hh (2.1) emcIniFile.cc/hh '' #include / M_PI. #include “emcIniFile.hh“ 该文件定义了一些 INI 文件中字符的赋值，包括 一个 TURE 或者 FAULSE，单位 mm ,m，角度，直线，旋 转等等。 (2.2) iniaxis.cc/hh #include #include / NULL #include / atol(), _itoa() #include / strcmp() #include / isdigit() #include #include #include “emc.hh“ #include “rcs_print.hh“ #include “emcIniFile.hh“ #include “iniaxis.hh“/ these decls #include “emcglb.h“/ EMC_DEBUG #include “emccfg.h“/ default values for globals#include “inihal.hh“ 该文件主要用到了两个函数：loadaxis 以及 iniaxis。前一个函数 loadaixs 是对 INI 文件中的轴类型，轴单元， 最大最小位置限值，误差限值，最大速度，加速度，加加速度等初始化参数进行读取并存储在tcRunCycle(tp, tc, primary_after = tcGetPos(tc);pmCartCartSub(primary_after.tran, primary_before.tran, primary_displacement.a = primary_after.a - primary_before.a;primary_displacement.b = primary_after.b - primary_before.b;primary_displacement.c = primary_after.c - primary_before.c;primary_displacement.u = primary_after.u - primary_before.u;primary_displacement.v = primary_after.v - primary_before.v;primary_displacement.w = primary_after.w - primary_before.w; 调用之前的函数，计算当前值，然后运行一个周期，再次获取新的位置，然后分别计算各轴位移量。 下一步计算属于混合模式下（即将几段相似的程序进行合并）的运动控制：同样进行条件判断，之后计 算前后两段运动的速度，位移等等，最后输出前后两端的位移大小，实现合并。 （15）最后对一些错误信息进行判断和验证。保证正确输出。备注：在 tp.c 中轨迹规划是如何完成的： （1）解释调用tpAddLine还是tpAddCircle?主要是依据 MDI 或者 G 代码的输入； （2）tpRunCycle 在每一个 TRAJ_PERIOD 周期内进行调用，从而更新 currentPos； （3）currentPos 最终反馈回 HAL 对应的是 axis.X.motor-pos-cmd HAL pins。在 tpruncycle 中： 判断 tc 队列是否为空，if(!tc)；运动队列为空就表示已经到了程序的终点或者说队列处于饥饿状态， 需要存入数据： 此时，采取以下动作：（1）初始化一个空的运动队列；（2）通过 tp->goalPos = tp->currentPos and tp->done = 1 来终止机器的动作；（3）调用 tpResume(tp)然后等待队列 tc 中写入东西。 判断是否有异常终止信息 if(tp->aborting)； 此时，采取以下动作：(1) 将当前的速度设置为 0；（2）通过 tp->goalPos = tp->currentPos and tp- >done = 1 来终止机器的动作； 判断是否当前命令行执行完毕 if (tc->target = tc->progress)： 此时，采取以下动作：(1) 将当前的命令行从队列中删除；（2）将下一个命令载入到队列中。（4.3）cubic.c 三次样条插值（5）MotionMotion 部分主要是（5.1）command.c'' #include #include #include “posemath.h“ #include “rtapi.h“ #include “hal.h“ #include “motion.h“ #include “motion_debug.h“ #include “motion_struct.h“ #include “emcmotglb.h“ #include “mot_priv.h“ #include “rtapi_math.h“ #include “motion_types.h“ 该函数主要是通过用户空间获取命令，执行不同的动作，这些命令结构体为 emcmotCommand- >command，而全部动作值都保存为 EMCMOT_COMMAND 在 motion.h 中。 如果想要进行添加新的信号参数，你就需要做以下的工作： （1）在 motion.h 中添加新的配置或者轴参数'foo'。 （2）在 motion.h 中添加'EMCMOT_SET_FOO“命令，在 cmd_code_t 中。 （3）在 command_t struct 中添加一个类 a field （4）在 command.c 中加一个大的选择开关从而控制'EMCMOT_SET_FOO' command。 （5）添加一个函数 emcSetFoo()在 taskintf.cc 中。 （6）在 emc.hh 中添加规范 emcSetFoo()。 （7）iniaxis.cc 或者 inixxx.cc 中加入代码从而获取 INI file 中的值，以及调用 emcSetFoo().注意，参量一 定不要重复。 （8）在 iniaxis.cc 中写入新值。 这说明你可以在 INI 文件中读取数据保存到共享内存，然后在运动控制器中调用。如果你想通过 NML 实现数据操作，还应该做以下： （9）定义#define EMC_SET_FOO_TYPE 在 emc.hh 中。 （10）定义一个类 EMC_SET_FOO 枣 emc.hh 中。 （11）在 emctaskmain.cc 中添加一个大的状态控制开关，从而在接收到 NML 信息之后调用 emcSetFoo()。（12）在 emc.cc,中添加两个与查找和设计新的命令相关的大的状态开关控制。好的，说完这些我们进行逐一介绍该函数的主程序。 （1）checkAllHomed(void) 根据名字就很好猜到，这是检查各轴是否处于原点。 （2）limits_ok()/jog_ok() 检查限位以及各轴是否准备好。 （3）refresh_jog_limits（） 重新检查限位；如果是从原点开始的，则直接重新给限位赋值，如果不是， 则在原有位置信息的基础上加上限位大小； （4）inRange() 检查轴是否在限定范围内运行。如果是，返回非零值，如果超过，返回零。 （5）clearHomes() 清零回位标志位； （6）emcmotDioWrite()/emcmotAioWrite 用于管脚写入值，对于数字 IO，写入 0 或者 1；对于模拟 IO， 输出实际值。 （7）i