datasheet (3).pdf - EEWeb

More documents

Recommendations

Info

dsPIC33FJ32MC302/304, dsPIC33FJ64MCX02/X04 AND dsPIC33FJ128MCX02/X04 FIGURE 21-1: ECAN MODULE BLOCK DIAGRAM Transmit Byte Sequencer DMA Controller TRB7 TX/RX Buffer Control Register TRB6 TX/RX Buffer Control Register TRB5 TX/RX Buffer Control Register TRB4 TX/RX Buffer Control Register TRB3 TX/RX Buffer Control Register TRB2 TX/RX Buffer Control Register TRB1 TX/RX Buffer Control Register TRB0 TX/RX Buffer Control Register CAN Protocol Engine C1Tx Message Assembly Buffer C1Rx RXF15 Filter RXF14 Filter RXF13 Filter RXF12 Filter RXF11 Filter RXF10 Filter RXF9 Filter RXF8 Filter RXF7 Filter RXF6 Filter RXF5 Filter RXF4 Filter RXF3 Filter RXF2 Filter RXF1 Filter RXF0 Filter Control Configuration Logic RXM2 Mask RXM1 Mask RXM0 Mask DS70291E-page 248 © 2011 Microchip Technology Inc. CPU Bus Interrupts
dsPIC33FJ32MC302/304, dsPIC33FJ64MCX02/X04 AND dsPIC33FJ128MCX02/X04 21.3 Modes of Operation The ECAN module can operate in one of several operation modes selected by the user. These modes include: • Initialization mode • Disable mode • Normal Operation mode • Listen Only mode • Listen All Messages mode • Loopback mode Modes are requested by setting the REQOP bits (CiCTRL1). Entry into a mode is Acknowledged by monitoring the OPMODE bits (CiCTRL1). The module does not change the mode and the OPMODE bits until a change in mode is acceptable, generally during bus Idle time, which is defined as at least 11 consecutive recessive bits. 21.3.1 INITIALIZATION MODE In the Initialization mode, the module does not transmit or receive. The error counters are cleared and the interrupt flags remain unchanged. The user application has access to Configuration registers that are access restricted in other modes. The module protects the user from accidentally violating the CAN protocol through programming errors. All registers which control the configuration of the module can not be modified while the module is on-line. The ECAN module is not allowed to enter the Configuration mode while a transmission is taking place. The Configuration mode serves as a lock to protect the following registers: • All Module Control registers • Baud Rate and Interrupt Configuration registers • Bus Timing registers • Identifier Acceptance Filter registers • Identifier Acceptance Mask registers 21.3.2 DISABLE MODE In Disable mode, the module does not transmit or receive. The module has the ability to set the WAKIF bit due to bus activity, however, any pending interrupts remains and the error counters retains their value. If the REQOP bits (CiCTRL1) = 001, the module enters the Module Disable mode. If the module is active, the module waits for 11 recessive bits on the CAN bus, detect that condition as an Idle bus, then accept the module disable command. When the OPMODE bits (CiCTRL1) = 001, that indicates whether the module successfully went into Module Disable mode. The I/O pins reverts to normal I/O function when the module is in the Module Disable mode. The module can be programmed to apply a low-pass filter function to the CiRX input line while the module or the CPU is in Sleep mode. The WAKFIL bit (CiCFG2) enables or disables the filter. Note: Typically, if the ECAN module is allowed to transmit in a particular mode of operation and a transmission is requested immediately after the ECAN module has been placed in that mode of operation, the module waits for 11 consecutive recessive bits on the bus before starting transmission. If the user switches to Disable mode within this 11-bit period, then this transmission is aborted and the corresponding TXABT bit is set and TXREQ bit is cleared. 21.3.3 NORMAL OPERATION MODE Normal Operation mode is selected when REQOP = 000. In this mode, the module is activated and the I/O pins assumes the CAN bus functions. The module transmits and receive CAN bus messages via the CiTX and CiRX pins. 21.3.4 LISTEN ONLY MODE If the Listen Only mode is activated, the module on the CAN bus is passive. The transmitter buffers revert to the port I/O function. The receive pins remain inputs. For the receiver, no error flags or Acknowledge signals are sent. The error counters are deactivated in this state. The Listen Only mode can be used for detecting the baud rate on the CAN bus. To use this, it is necessary that there are at least two further nodes that communicate with each other. 21.3.5 LISTEN ALL MESSAGES MODE The module can be set to ignore all errors and receive any message. The Listen All Messages mode is activated by setting REQOP = ‘111’. In this mode, the data which is in the message assembly buffer, until the time an error occurred, is copied in the receive buffer and can be read via the CPU interface. 21.3.6 LOOPBACK MODE If the Loopback mode is activated, the module connects the internal transmit signal to the internal receive signal at the module boundary. The transmit and receive pins revert to their port I/O function. © 2011 Microchip Technology Inc. DS70291E-page 249
Page 1 and 2:
dsPIC33FJ32MC302/304, dsPIC33FJ64MC
Page 3 and 4:
Page 5 and 6:
Page 7 and 8:
Page 9 and 10:
Page 11 and 12:
Page 13 and 14:
Page 15 and 16:
Page 17 and 18:
Page 19 and 20:
Page 21 and 22:
Page 23 and 24:
Page 25 and 26:
Page 27 and 28:
Page 29 and 30:
Page 31 and 32:
Page 33 and 34:
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
© 2011 Microchip Technology Inc. D
Page 49 and 50:
Page 51 and 52:
Page 53 and 54:
Page 55 and 56:
Page 57 and 58:
Page 59 and 60:
Page 61 and 62:
Page 63 and 64:
Page 65 and 66:
Page 67 and 68:
Page 69 and 70:
Page 71 and 72:
Page 73 and 74:
Page 75 and 76:
Page 77 and 78:
Page 79 and 80:
Page 81 and 82:
Page 83 and 84:
Page 85 and 86:
Page 87 and 88:
Page 89 and 90:
Page 91 and 92:
Page 93 and 94:
Page 95 and 96:
Page 97 and 98:
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Page 105 and 106:
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Page 119 and 120:
Page 121 and 122:
Page 123 and 124:
Page 125 and 126:
Page 127 and 128:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
Page 141 and 142:
Page 143 and 144:
Page 145 and 146:
Page 147 and 148:
Page 149 and 150:
Page 151 and 152:
Page 153 and 154:
Page 155 and 156:
Page 157 and 158:
Page 159 and 160:
Page 161 and 162:
Page 163 and 164:
Page 165 and 166:
Page 167 and 168:
Page 169 and 170:
Page 171 and 172:
Page 173 and 174:
Page 175 and 176:
Page 177 and 178:
Page 179 and 180:
Page 181 and 182:
Page 183 and 184:
Page 185 and 186:
Page 187 and 188:
Page 189 and 190:
Page 191 and 192:
Page 193 and 194:
Page 195 and 196:
Page 197 and 198: dsPIC33FJ32MC302/304, dsPIC33FJ64MC
Page 247: dsPIC33FJ32MC302/304, dsPIC33FJ64MC
Page 299 and 300:
Page 301 and 302:
Page 303 and 304:
Page 305 and 306:
Page 307 and 308:
Page 309 and 310:
Page 311 and 312:
Page 313 and 314:
Page 315 and 316:
Page 317 and 318:
Page 319 and 320:
Page 321 and 322:
Page 323 and 324:
Page 325 and 326:
Page 327 and 328:
Page 329 and 330:
Page 331 and 332:
Page 333 and 334:
Page 335 and 336:
Page 337 and 338:
Page 339 and 340:
Page 341 and 342:
Page 343 and 344:
Page 345 and 346:
Page 347 and 348:
Page 349 and 350:
Page 351 and 352:
Page 353 and 354:
Page 355 and 356:
Page 357 and 358:
Page 359 and 360:
Page 361 and 362:
Page 363 and 364:
Page 365 and 366:
Page 367 and 368:
Page 369 and 370:
Page 371 and 372:
Page 373 and 374:
Page 375 and 376:
Page 377 and 378:
Page 379 and 380:
Page 381 and 382:
Page 383 and 384:
Page 385 and 386:
Page 387 and 388:
Page 389 and 390:
Page 391 and 392:
Page 393 and 394:
Page 395 and 396:
Page 397 and 398:
Page 399 and 400:
Page 401 and 402:
Page 403 and 404:
Page 405 and 406:
Page 407 and 408:
Page 409 and 410:
Page 411 and 412:
Page 413 and 414:
Page 415 and 416:
Page 417 and 418:
Page 419 and 420:
Page 421 and 422:
Page 423 and 424:
Page 425 and 426:
Page 427 and 428:
Page 429 and 430:
Page 431 and 432:
Page 433 and 434:
Page 435 and 436:
show all

datasheet (3).pdf - EEWeb

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?