MX64.cpp

00001 /* mbed MX-64 Servo Library
00002  *
00003  * Copyright (c) 2010, cstyles (http://mbed.org)
00004  *
00005  * Permission is hereby granted, free of charge, to any person obtaining a copy
00006  * of this software and associated documentation files (the "Software"), to deal
00007  * in the Software without restriction, including without limitation the rights
00008  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00009  * copies of the Software, and to permit persons to whom the Software is
00010  * furnished to do so, subject to the following conditions:
00011  *
00012  * The above copyright notice and this permission notice shall be included in
00013  * all copies or substantial portions of the Software.
00014  *
00015  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00016  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00017  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00018  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00019  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00020  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00021  * THE SOFTWARE.
00022  */
00023 
00024 #include "MX64.h"
00025 #include "mbed.h"
00026 
00027 MX64::MX64(PinName tx, PinName rx, int ID, int baud)
00028         : _mx64(tx,rx) {
00029     _baud = baud;
00030     _ID = ID;
00031     _mx64.baud(_baud);
00032 
00033 }
00034 
00035 // Set the mode of the servo
00036 //  0 = Positional (0-300 degrees)
00037 //  1 = Rotational -1 to 1 speed
00038 int MX64::SetMode(int mode) {
00039 
00040     if (mode == 1) { // set CR
00041         SetCWLimit(0);
00042         SetCCWLimit(0);
00043         SetCRSpeed(0.0);
00044     } else {
00045         SetCWLimit(0);
00046         SetCCWLimit(300);
00047         SetCRSpeed(0.0);
00048     }
00049     return(0);
00050 }
00051 
00052 
00053 // if flag[0] is set, were blocking
00054 // if flag[1] is set, we're registering
00055 // they are mutually exclusive operations
00056 int MX64::SetGoal(int degrees, int flags) {
00057 
00058     char reg_flag = 0;
00059     char data[2];
00060 
00061     // set the flag is only the register bit is set in the flag
00062     if (flags == 0x2) {
00063         reg_flag = 1;
00064     }
00065 
00066     // 1023 / 300 * degrees
00067     short goal = (4095 * degrees) / 360;
00068 #ifdef MX64_DEBUG
00069     printf("SetGoal to 0x%x\n",goal);
00070 #endif
00071 
00072     data[0] = goal & 0xff; // bottom 8 bits
00073     data[1] = goal >> 8;   // top 8 bits
00074 
00075     // write the packet, return the error code
00076     int rVal = write(_ID, MX64_REG_GOAL_POSITION, 2, data, reg_flag);
00077 
00078     if (flags == 1) {
00079         // block until it comes to a halt
00080         while (isMoving()) {}
00081     }
00082     return(rVal);
00083 }
00084 
00085 // if flag[0] is set, were blocking
00086 // if flag[1] is set, we're registering
00087 // they are mutually exclusive operations
00088 int MX64::SetGoalSpeed(int degrees, int speed, int flags) {
00089 
00090     char reg_flag = 0;
00091     char data[4];
00092 
00093     // set the flag is only the register bit is set in the flag
00094     if (flags == 0x2) {
00095         reg_flag = 1;
00096     }
00097 
00098     // 1023 / 300 * degrees
00099     short goal = (1023 * degrees) / 360;
00100     short sp = (1023 * speed) / 100;
00101     
00102 #ifdef AX12_DEBUG
00103     printf("SetGoalSpeed to 0x%x with speed 0x%x\n",goal,sp);
00104 #endif
00105 
00106     data[0] = goal & 0xff; // bottom 8 bits
00107     data[1] = goal >> 8;   // top 8 bits
00108 
00109     data[2] = sp & 0xff;
00110     data[3] = sp >> 8;
00111     
00112     // write the packet, return the error code
00113     int rVal = write(_ID, MX64_REG_GOAL_POSITION, 4, data, reg_flag);
00114 
00115     if (flags == 1) {
00116         // block until it comes to a halt
00117         while (isMoving()) {}
00118     }
00119     return(rVal);
00120 }
00121 
00122 // Set continuous rotation speed from -1 to 1
00123 int MX64::SetCRSpeed(float speed) {
00124 
00125     // bit 10     = direction, 0 = CCW, 1=CW
00126     // bits 9-0   = Speed
00127     char data[2];
00128 
00129     int goal = (0x3ff * abs(speed));
00130 
00131     // Set direction CW if we have a negative speed
00132     if (speed < 0) {
00133         goal |= (0x1 << 10);
00134     }
00135 
00136     data[0] = goal & 0xff; // bottom 8 bits
00137     data[1] = goal >> 8;   // top 8 bits
00138 
00139     // write the packet, return the error code
00140     int rVal = write(_ID, 0x20, 2, data);
00141 
00142     return(rVal);
00143 }
00144 
00145 
00146 int MX64::SetCWLimit (int degrees) {
00147 
00148     char data[2];
00149 
00150     // 1023 / 300 * degrees
00151     short limit = (4095 * degrees) / 360;
00152 
00153 #ifdef MX64_DEBUG
00154     printf("SetCWLimit to 0x%x\n",limit);
00155 #endif
00156 
00157     data[0] = limit & 0xff; // bottom 8 bits
00158     data[1] = limit >> 8;   // top 8 bits
00159 
00160     // write the packet, return the error code
00161     return (write(_ID, MX64_REG_CW_LIMIT, 2, data));
00162 
00163 }
00164 
00165 int MX64::SetCCWLimit (int degrees) {
00166 
00167     char data[2];
00168 
00169     // 1023 / 300 * degrees
00170     short limit = (4095 * degrees) / 360;
00171 
00172 #ifdef MX64_DEBUG
00173     printf("SetCCWLimit to 0x%x\n",limit);
00174 #endif
00175 
00176     data[0] = limit & 0xff; // bottom 8 bits
00177     data[1] = limit >> 8;   // top 8 bits
00178 
00179     // write the packet, return the error code
00180     return (write(_ID, MX64_REG_CCW_LIMIT, 2, data));
00181 }
00182 
00183 
00184 int MX64::SetID (int CurrentID, int NewID) {
00185 
00186     char data[1];
00187     data[0] = NewID;
00188 
00189 #ifdef MX64_DEBUG
00190     printf("Setting ID from 0x%x to 0x%x\n",CurrentID,NewID);
00191 #endif
00192 
00193     return (write(CurrentID, MX64_REG_ID, 1, data));
00194 
00195 }
00196 
00197 
00198 int MX64::SetBaud (int baud) {
00199 
00200     char data[1];
00201     data[0] = baud;
00202 
00203 #ifdef MX64_DEBUG
00204     printf("Setting Baud rate to %d\n",baud);
00205 #endif
00206 
00207     return (write(0xFE, MX64_REG_BAUD, 1, data));
00208 
00209 }
00210 
00211 
00212 
00213 // return 1 is the servo is still in flight
00214 int MX64::isMoving(void) {
00215 
00216     char data[1];
00217     read(_ID,MX64_REG_MOVING,1,data);
00218     return(data[0]);
00219 }
00220 
00221 
00222 void MX64::trigger(void) {
00223 
00224     char TxBuf[16];
00225     char sum = 0;
00226 
00227 #ifdef MX64_TRIGGER_DEBUG
00228     // Build the TxPacket first in RAM, then we'll send in one go
00229     printf("\nTriggered\n");
00230     printf("\nTrigger Packet\n  Header : 0xFF, 0xFF\n");
00231 #endif
00232 
00233     TxBuf[0] = 0xFF;
00234     TxBuf[1] = 0xFF;
00235 
00236     // ID - Broadcast
00237     TxBuf[2] = 0xFE;
00238     sum += TxBuf[2];
00239 
00240 #ifdef MX64_TRIGGER_DEBUG
00241     printf("  ID : %d\n",TxBuf[2]);
00242 #endif
00243 
00244     // Length
00245     TxBuf[3] = 0x02;
00246     sum += TxBuf[3];
00247 
00248 #ifdef MX64_TRIGGER_DEBUG
00249     printf("  Length %d\n",TxBuf[3]);
00250 #endif
00251 
00252     // Instruction - ACTION
00253     TxBuf[4] = 0x04;
00254     sum += TxBuf[4];
00255 
00256 #ifdef MX64_TRIGGER_DEBUG
00257     printf("  Instruction 0x%X\n",TxBuf[5]);
00258 #endif
00259 
00260     // Checksum
00261     TxBuf[5] = 0xFF - sum;
00262 #ifdef MX64_TRIGGER_DEBUG
00263     printf("  Checksum 0x%X\n",TxBuf[5]);
00264 #endif
00265 
00266     // Transmit the packet in one burst with no pausing
00267     for (int i = 0; i < 6 ; i++) {
00268         _mx64.putc(TxBuf[i]);
00269     }
00270 
00271     // This is a broadcast packet, so there will be no reply
00272     return;
00273 }
00274 
00275 
00276 float MX64::GetPosition(void) {
00277 
00278 #ifdef MX64_DEBUG
00279     printf("\nGetPosition(%d)",_ID);
00280 #endif
00281 
00282     char data[2];
00283 
00284     int ErrorCode = read(_ID, MX64_REG_POSITION, 2, data);
00285     short position = data[0] + (data[1] << 8);
00286     float angle = (position * 360)/4096;
00287 
00288     return (angle);
00289 }
00290 
00291 
00292 float MX64::GetTemp (void) {
00293 
00294 #ifdef MX64_DEBUG
00295     printf("\nGetTemp(%d)",_ID);
00296 #endif
00297 
00298     char data[1];
00299     int ErrorCode = read(_ID, MX64_REG_TEMP, 1, data);
00300     float temp = data[0];
00301     return(temp);
00302 }
00303 
00304 
00305 float MX64::GetVolts (void) {
00306 
00307 #ifdef MX64_DEBUG
00308     printf("\nGetVolts(%d)",_ID);
00309 #endif
00310 
00311     char data[1];
00312     int ErrorCode = read(_ID, MX64_REG_VOLTS, 1, data);
00313     float volts = data[0]/10.0;
00314     return(volts);
00315 }
00316 
00317 
00318 int MX64::read(int ID, int start, int bytes, char* data) {
00319 
00320     char PacketLength = 0x4;
00321     char TxBuf[16];
00322     char sum = 0;
00323     char Status[16];
00324 
00325     Status[4] = 0xFE; // return code
00326 
00327 #ifdef MX64_READ_DEBUG
00328     printf("\nread(%d,0x%x,%d,data)\n",ID,start,bytes);
00329 #endif
00330 
00331     // Build the TxPacket first in RAM, then we'll send in one go
00332 #ifdef MX64_READ_DEBUG
00333     printf("\nInstruction Packet\n  Header : 0xFF, 0xFF\n");
00334 #endif
00335 
00336     TxBuf[0] = 0xff;
00337     TxBuf[1] = 0xff;
00338 
00339     // ID
00340     TxBuf[2] = ID;
00341     sum += TxBuf[2];
00342 
00343 #ifdef MX64_READ_DEBUG
00344     printf("  ID : %d\n",TxBuf[2]);
00345 #endif
00346 
00347     // Packet Length
00348     TxBuf[3] = PacketLength;    // Length = 4 ; 2 + 1 (start) = 1 (bytes)
00349     sum += TxBuf[3];            // Accululate the packet sum
00350 
00351 #ifdef MX64_READ_DEBUG
00352     printf("  Length : 0x%x\n",TxBuf[3]);
00353 #endif
00354 
00355     // Instruction - Read
00356     TxBuf[4] = 0x2;
00357     sum += TxBuf[4];
00358 
00359 #ifdef MX64_READ_DEBUG
00360     printf("  Instruction : 0x%x\n",TxBuf[4]);
00361 #endif
00362 
00363     // Start Address
00364     TxBuf[5] = start;
00365     sum += TxBuf[5];
00366 
00367 #ifdef MX64_READ_DEBUG
00368     printf("  Start Address : 0x%x\n",TxBuf[5]);
00369 #endif
00370 
00371     // Bytes to read
00372     TxBuf[6] = bytes;
00373     sum += TxBuf[6];
00374 
00375 #ifdef MX64_READ_DEBUG
00376     printf("  No bytes : 0x%x\n",TxBuf[6]);
00377 #endif
00378 
00379     // Checksum
00380     TxBuf[7] = 0xFF - sum;
00381 #ifdef MX64_READ_DEBUG
00382     printf("  Checksum : 0x%x\n",TxBuf[7]);
00383 #endif
00384 
00385     // Transmit the packet in one burst with no pausing
00386     for (int i = 0; i<8 ; i++) {
00387         _mx64.putc(TxBuf[i]);
00388     }
00389 
00390     // Wait for the bytes to be transmitted
00391     wait (0.00002);
00392 
00393     // Skip if the read was to the broadcast address
00394     if (_ID != 0xFE) {
00395 
00396 
00397 
00398         // response packet is always 6 + bytes
00399         // 0xFF, 0xFF, ID, Length Error, Param(s) Checksum
00400         // timeout is a little more than the time to transmit
00401         // the packet back, i.e. (6+bytes)*10 bit periods
00402 
00403         int timeout = 0;
00404         int plen = 0;
00405         while ((timeout < ((6+bytes)*10)) && (plen<(6+bytes))) {
00406 
00407             if (_mx64.readable()) {
00408                 Status[plen] = _mx64.getc();
00409                 plen++;
00410                 timeout = 0;
00411             }
00412 
00413             // wait for the bit period
00414             wait (1.0/_baud);
00415             timeout++;
00416         }
00417 
00418         if (timeout == ((6+bytes)*10) ) {
00419             return(-1);
00420         }
00421 
00422         // Copy the data from Status into data for return
00423         for (int i=0; i < Status[3]-2 ; i++) {
00424             data[i] = Status[5+i];
00425         }
00426 
00427 #ifdef MX64_READ_DEBUG
00428         printf("\nStatus Packet\n");
00429         printf("  Header : 0x%x\n",Status[0]);
00430         printf("  Header : 0x%x\n",Status[1]);
00431         printf("  ID : 0x%x\n",Status[2]);
00432         printf("  Length : 0x%x\n",Status[3]);
00433         printf("  Error Code : 0x%x\n",Status[4]);
00434 
00435         for (int i=0; i < Status[3]-2 ; i++) {
00436             printf("  Data : 0x%x\n",Status[5+i]);
00437         }
00438 
00439         printf("  Checksum : 0x%x\n",Status[5+(Status[3]-2)]);
00440 #endif
00441 
00442     } // if (ID!=0xFE)
00443 
00444     return(Status[4]);
00445 }
00446 
00447 
00448 int MX64::write(int ID, int start, int bytes, char* data, int flag) {
00449 // 0xff, 0xff, ID, Length, Intruction(write), Address, Param(s), Checksum
00450 
00451     char TxBuf[16];
00452     char sum = 0;
00453     char Status[6];
00454 
00455 #ifdef MX64_WRITE_DEBUG
00456     printf("\nwrite(%d,0x%x,%d,data,%d)\n",ID,start,bytes,flag);
00457 #endif
00458 
00459     // Build the TxPacket first in RAM, then we'll send in one go
00460 #ifdef MX64_WRITE_DEBUG
00461     printf("\nInstruction Packet\n  Header : 0xFF, 0xFF\n");
00462 #endif
00463 
00464     TxBuf[0] = 0xff;
00465     TxBuf[1] = 0xff;
00466 
00467     // ID
00468     TxBuf[2] = ID;
00469     sum += TxBuf[2];
00470 
00471 #ifdef MX64_WRITE_DEBUG
00472     printf("  ID : %d\n",TxBuf[2]);
00473 #endif
00474 
00475     // packet Length
00476     TxBuf[3] = 3+bytes;
00477     sum += TxBuf[3];
00478 
00479 #ifdef MX64_WRITE_DEBUG
00480     printf("  Length : %d\n",TxBuf[3]);
00481 #endif
00482 
00483     // Instruction
00484     if (flag == 1) {
00485         TxBuf[4]=0x04;
00486         sum += TxBuf[4];
00487     } else {
00488         TxBuf[4]=0x03;
00489         sum += TxBuf[4];
00490     }
00491 
00492 #ifdef MX64_WRITE_DEBUG
00493     printf("  Instruction : 0x%x\n",TxBuf[4]);
00494 #endif
00495 
00496     // Start Address
00497     TxBuf[5] = start;
00498     sum += TxBuf[5];
00499 
00500 #ifdef MX64_WRITE_DEBUG
00501     printf("  Start : 0x%x\n",TxBuf[5]);
00502 #endif
00503 
00504     // data
00505     for (char i=0; i<bytes ; i++) {
00506         TxBuf[6+i] = data[i];
00507         sum += TxBuf[6+i];
00508 
00509 #ifdef MX64_WRITE_DEBUG
00510         printf("  Data : 0x%x\n",TxBuf[6+i]);
00511 #endif
00512 
00513     }
00514 
00515     // checksum
00516     TxBuf[6+bytes] = 0xFF - sum;
00517 
00518 #ifdef MX64_WRITE_DEBUG
00519     printf("  Checksum : 0x%x\n",TxBuf[6+bytes]);
00520 #endif
00521 
00522     // Transmit the packet in one burst with no pausing
00523     for (int i = 0; i < (7 + bytes) ; i++) {
00524         _mx64.putc(TxBuf[i]);
00525     }
00526 
00527     // Wait for data to transmit
00528     wait (0.00002);
00529 
00530     // make sure we have a valid return
00531     Status[4]=0x00;
00532 
00533     // we'll only get a reply if it was not broadcast
00534     if (_ID!=0xFE) {
00535 
00536 
00537         // response packet is always 6 bytes
00538         // 0xFF, 0xFF, ID, Length Error, Param(s) Checksum
00539         // timeout is a little more than the time to transmit
00540         // the packet back, i.e. 60 bit periods, round up to 100
00541         int timeout = 0;
00542         int plen = 0;
00543         while ((timeout < 100) && (plen<6)) {
00544 
00545             if (_mx64.readable()) {
00546                 Status[plen] = _mx64.getc();
00547                 plen++;
00548                 timeout = 0;
00549             }
00550 
00551             // wait for the bit period
00552             wait (1.0/_baud);
00553             timeout++;
00554         }
00555 
00556 
00557         // Build the TxPacket first in RAM, then we'll send in one go
00558 #ifdef MX64_WRITE_DEBUG
00559         printf("\nStatus Packet\n  Header : 0x%X, 0x%X\n",Status[0],Status[1]);
00560         printf("  ID : %d\n",Status[2]);
00561         printf("  Length : %d\n",Status[3]);
00562         printf("  Error : 0x%x\n",Status[4]);
00563         printf("  Checksum : 0x%x\n",Status[5]);
00564 #endif
00565 
00566 
00567     }
00568 
00569     return(Status[4]); // return error code
00570 }