main.c

   1 /*
   2  * Copyright (c) 2011, Olivier MATZ <zer0@droids-corp.org>
   3  * All rights reserved.
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are met:
   6  *
   7  *     * Redistributions of source code must retain the above copyright
   8  *       notice, this list of conditions and the following disclaimer.
   9  *     * Redistributions in binary form must reproduce the above copyright
  10  *       notice, this list of conditions and the following disclaimer in the
  11  *       documentation and/or other materials provided with the distribution.
  12  *     * Neither the name of the University of California, Berkeley nor the
  13  *       names of its contributors may be used to endorse or promote products
  14  *       derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
  17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  19  * DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
  20  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  23  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  25  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include <aversive.h>
  29 #include <aversive/queue.h>
  30 #include <aversive/endian.h>
  31 #include <aversive/wait.h>
  32 #include <aversive/error.h>
  33
  34 #include <uart.h>
  35
  36 #include <stdio.h>
  37 #include <string.h>
  38 #include <stdint.h>
  39 #include <inttypes.h>
  40 #include <stdlib.h>
  41 #include <stdarg.h>
  42 #include <errno.h>
  43 #include <ctype.h>
  44
  45 #include <scheduler.h>
  46 #include <clock_time.h>
  47 #include <parse.h>
  48 #include <rdline.h>
  49 #include <timer.h>
  50
  51 #include "xbee_neighbor.h"
  52 #include "xbee_atcmd.h"
  53 #include "xbee_stats.h"
  54 #include "xbee_buf.h"
  55 #include "xbee_proto.h"
  56 #include "xbee.h"
  57 #include "cmdline.h"
  58 #include "callout.h"
  59 #include "rc_proto.h"
  60 #include "spi_servo.h"
  61 #include "main.h"
  62
  63 struct xbeeboard xbeeboard;
  64 volatile uint16_t global_ms;
  65 struct callout_manager cm;
  66
  67 #define TIMEOUT_MS 1000
  68
  69 /* global xbee device */
  70 struct xbee_dev *xbee_dev;
  71
  72 /* events */
  73 //static struct event stdin_read_event, xbee_read_event;
  74
  75 /* parameters */
  76 int xbee_raw = 0;
  77 int xbee_hexdump = 0;
  78 int xbee_debug = 0;
  79
  80 int xbee_cmdline_input_enabled = 1;
  81
  82 static struct xbee_ctx xbee_ctx[XBEE_MAX_CHANNEL];
  83
  84 static void hexdump(const char *title, const void *buf, unsigned int len)
  85 {
  86         unsigned int i, out, ofs;
  87         const unsigned char *data = buf;
  88 #define LINE_LEN 80
  89         char line[LINE_LEN];    /* space needed 8+16*3+3+16 == 75 */
  90
  91         printf_P(PSTR("%s at [%p], len=%d\r\n"), title, data, len);
  92         ofs = 0;
  93         while (ofs < len) {
  94                 /* format 1 line in the buffer, then use printk to print them */
  95                 out = snprintf_P(line, LINE_LEN, PSTR("%08X"), ofs);
  96                 for (i=0; ofs+i < len && i<16; i++)
  97                         out += snprintf_P(line+out, LINE_LEN - out,
  98                                           PSTR(" %02X"),
  99                                           data[ofs+i]&0xff);
 100                 for (;i<=16;i++)
 101                         out += snprintf(line+out, LINE_LEN - out, "   ");
 102                 for (i=0; ofs < len && i<16; i++, ofs++) {
 103                         unsigned char c = data[ofs];
 104                         if (!isascii(c) || !isprint(c))
 105                                 c = '.';
 106                         out += snprintf_P(line+out,
 107                                           LINE_LEN - out,
 108                                           PSTR("%c"), c);
 109                 }
 110                 printf_P(PSTR("%s\r\n"), line);
 111         }
 112 }
 113
 114 static int parse_xmit_status(struct xbee_ctx *ctx,
 115                              struct xbee_xmit_status_hdr *frame, unsigned len)
 116 {
 117         (void)len;
 118
 119         if (ctx == NULL) {
 120                 printf_P(PSTR("no context\r\n"));
 121                 return -1;
 122         }
 123
 124         /* see if it matches a xmit query (atcmd_query must be NULL) */
 125         if (ctx->atcmd_query[0] != '\0') {
 126                 printf_P(PSTR("invalid response 2\r\n"));
 127                 return -1;
 128         }
 129
 130         /* XXX use defines for these values */
 131         if (frame->delivery_status == 0x00)
 132                 printf_P(PSTR("Success\r\n"));
 133         else if (frame->delivery_status == 0x01)
 134                 printf_P(PSTR("MAC ACK Failure\r\n"));
 135         else if (frame->delivery_status == 0x15)
 136                 printf_P(PSTR("Invalid destination endpoint\r\n"));
 137         else if (frame->delivery_status == 0x21)
 138                 printf_P(PSTR("Network ACK Failure\r\n"));
 139         else if (frame->delivery_status == 0x25)
 140                 printf_P(PSTR("Route Not Found\r\n"));
 141
 142         return 0;
 143 }
 144
 145 static int dump_atcmd(struct xbee_ctx *ctx, struct xbee_atresp_hdr *frame,
 146                unsigned len)
 147 {
 148         char atcmd_str[3];
 149         const struct xbee_atcmd *cmd_pgm;
 150         struct xbee_atcmd cmd;
 151         union {
 152                 uint8_t u8;
 153                 uint16_t u16;
 154                 uint32_t u32;
 155                 int16_t s16;
 156         } __attribute__((packed)) *result;
 157
 158         if (ctx == NULL) {
 159                 printf_P(PSTR("no context\r\n"));
 160                 return -1;
 161         }
 162
 163         /* get AT command from frame */
 164         memcpy(atcmd_str, &frame->cmd, 2);
 165         atcmd_str[2] = '\0';
 166
 167         /* see if it matches query */
 168         if (memcmp(atcmd_str, ctx->atcmd_query, 2)) {
 169                 printf_P(PSTR("invalid response <%c%c><%s><%s>\r\n"),
 170                          frame->cmd & 0xFF,
 171                          (frame->cmd >> 8) & 0xFF,
 172                          atcmd_str, ctx->atcmd_query);
 173                 return -1;
 174         }
 175
 176         /* see if it exists */
 177         cmd_pgm = xbee_atcmd_lookup_name(atcmd_str);
 178         if (cmd_pgm == NULL) {
 179                 printf_P(PSTR("unknown response\r\n"));
 180                 return -1;
 181         }
 182         memcpy_P(&cmd, cmd_pgm, sizeof(cmd));
 183
 184         /* bad status */
 185         if (frame->status == 1) {
 186                 printf_P(PSTR("Status is error\r\n"));
 187                 return -1;
 188         }
 189         else if (frame->status == 2) {
 190                 printf_P(PSTR("Invalid command\r\n"));
 191                 return -1;
 192         }
 193         else if (frame->status == 3) {
 194                 printf_P(PSTR("Invalid parameter\r\n"));
 195                 return -1;
 196         }
 197         else if (frame->status != 0) {
 198                 printf_P(PSTR("Unknown status error %d\r\n"), frame->status);
 199                 return -1;
 200         }
 201
 202         /* callback */
 203         if (ctx->func != NULL)
 204                 ctx->func(frame, len, ctx->arg);
 205
 206         /* dump frame */
 207         result = (void *)frame->data;
 208         len -= offsetof(struct xbee_atresp_hdr, data);
 209         if (cmd.flags & XBEE_ATCMD_F_PARAM_U8 && len == sizeof(uint8_t))
 210                 printf_P(PSTR("<%s> is 0x%x\r\n"), atcmd_str, result->u8);
 211         else if (cmd.flags & XBEE_ATCMD_F_PARAM_U16 && len == sizeof(uint16_t))
 212                 printf_P(PSTR("<%s> is 0x%x\r\n"),
 213                          atcmd_str,
 214                          ntohs(result->u16));
 215         else if (cmd.flags & XBEE_ATCMD_F_PARAM_U32 && len == sizeof(uint32_t))
 216                 printf_P(PSTR("<%s> is 0x%"PRIx32"\r\n"),
 217                          atcmd_str,
 218                          ntohl(result->u32));
 219         else if (cmd.flags & XBEE_ATCMD_F_PARAM_S16 && len == sizeof(int16_t))
 220                 printf_P(PSTR("<%s> is %d\r\n"), atcmd_str, ntohs(result->s16));
 221         else if (len == 0)
 222                 printf_P(PSTR("no data, status ok\r\n"));
 223         else
 224                 hexdump("atcmd answer", frame->data, len);
 225
 226
 227         return 0;
 228 }
 229
 230
 231 int xbee_recv_data(struct xbee_recv_hdr *recvframe, unsigned len)
 232 {
 233         unsigned int datalen;
 234         struct rc_proto_hdr *rch = (struct rc_proto_hdr *) &recvframe->data;
 235
 236         if (len <  sizeof(*recvframe))
 237                 return -1;
 238
 239         datalen = len - sizeof(*recvframe);
 240         if (datalen < sizeof(struct rc_proto_hdr))
 241                 return -1;
 242
 243         switch (rch->type) {
 244                 case RC_PROTO_TYPE_CHANNEL: {
 245                         struct rc_proto_channel *rcc =
 246                                 (struct rc_proto_channel *) recvframe->data;
 247                         int16_t val;
 248                         if (datalen != sizeof(struct rc_proto_channel))
 249                                 return -1;
 250                         val = ntohs(rcc->axis[0]);
 251                         val >>= 6;
 252                         val += 512;
 253                         spi_servo_set(0, val);
 254                         break;
 255                                   }
 256                 case RC_PROTO_TYPE_RANGE: {
 257                         struct rc_proto_range *rcr =
 258                                 (struct rc_proto_range *) recvframe->data;
 259
 260                         if (datalen != sizeof(struct rc_proto_range))
 261                                 return -1;
 262
 263                         if (rcr->power_level >= MAX_POWER_LEVEL)
 264                                 return -1;
 265
 266                         rc_proto_rx_range(rcr->power_level);
 267
 268                         break;
 269                 }
 270                 default:
 271                         return -1;
 272         }
 273
 274         return 0;
 275 }
 276
 277 /* socat /dev/ttyUSB0,raw,echo=0,b115200 /dev/ttyACM1,raw,echo=0,b115200 */
 278 void xbee_rx(struct xbee_dev *dev, int channel, int type,
 279              void *frame, unsigned len, void *opaque)
 280 {
 281         struct xbee_ctx *ctx = opaque;
 282         int do_hexdump = xbee_hexdump;
 283
 284         if (xbee_debug)
 285                 printf_P(PSTR("type=0x%x, channel=%d, ctx=%p\r\n"),
 286                          type, channel, ctx);
 287
 288         /* if ctx is !NULL, it is an answer to a query */
 289         if (ctx != NULL) {
 290                 /* XXX only delete timeout if answer matched */
 291                 xbee_unload_timeout(ctx);
 292                 if (xbee_debug && ctx->atcmd_query)
 293                         printf_P(PSTR("Received answer to query <%c%c>\r\n"),
 294                                  ctx->atcmd_query[0], ctx->atcmd_query[1]);
 295         }
 296
 297         /* some additional checks before sending */
 298         switch (type) {
 299                 case XBEE_TYPE_MODEM_STATUS: {
 300                         printf_P(PSTR("Received Modem Status frame\r\n"));
 301                         break;
 302                 }
 303
 304                 case XBEE_TYPE_RMT_ATRESP: {
 305                         union {
 306                                 uint64_t u64;
 307                                 struct {
 308 #if BYTE_ORDER == LITTLE_ENDIAN
 309                                         uint32_t low;
 310                                         uint32_t high;
 311 #else
 312                                         uint32_t high;
 313                                         uint32_t low;
 314 #endif
 315                                 } u32;
 316                         } addr;
 317                         memcpy(&addr, frame, sizeof(addr));
 318                         addr.u64 = ntohll(addr.u64);
 319                         printf_P(PSTR("from remote address %"PRIx32"%"PRIx32"\r\n"),
 320                                  addr.u32.high, addr.u32.low);
 321
 322                         /* this answer contains an atcmd answer at offset 10 */
 323                         if (dump_atcmd(ctx, frame + 10, len - 10) < 0)
 324                                 do_hexdump = 1;
 325                         break;
 326                 }
 327                 case XBEE_TYPE_ATRESP: {
 328                         if (dump_atcmd(ctx, frame, len) < 0)
 329                                 do_hexdump = 1;
 330                         break;
 331                 }
 332
 333                 case XBEE_TYPE_XMIT_STATUS: {
 334                         if (parse_xmit_status(ctx, frame, len) < 0)
 335                                 do_hexdump = 1;
 336                         break;
 337                 }
 338
 339                 case XBEE_TYPE_RECV: {
 340                         if (xbee_recv_data(frame, len) < 0)
 341                                 do_hexdump = 1;
 342                         break;
 343                 }
 344
 345                 case XBEE_TYPE_ATCMD:
 346                 case XBEE_TYPE_ATCMD_Q:
 347                 case XBEE_TYPE_XMIT:
 348                 case XBEE_TYPE_EXPL_XMIT:
 349                 case XBEE_TYPE_RMT_ATCMD:
 350                 case XBEE_TYPE_EXPL_RECV:
 351                 case XBEE_TYPE_NODE_ID:
 352                 default:
 353                         printf_P(PSTR("Invalid frame\r\n"));
 354                         do_hexdump = 1;
 355                         break;
 356         }
 357
 358         if (do_hexdump)
 359                 hexdump("undecoded rx frame", frame, len);
 360
 361         /* restart command line if it was a blocking query */
 362         if (ctx != NULL) {
 363                 xbee_unregister_channel(dev, channel);
 364                 if (ctx->foreground) {
 365                         xbee_stdin_enable();
 366                         rdline_newline(&xbeeboard.rdl, xbeeboard.prompt);
 367                 }
 368         }
 369 }
 370
 371 static int xbeeapp_send(struct xbee_ctx *ctx, int type, void *buf, unsigned len,
 372                         int foreground)
 373 {
 374         int ret;
 375         int channel;
 376
 377         if (len > XBEE_MAX_FRAME_LEN) {
 378                 printf_P(PSTR("frame too large\r\n"));
 379                 return -1;
 380         }
 381
 382         /* register a channel */
 383         channel = xbee_register_channel(xbee_dev, XBEE_CHANNEL_ANY,
 384                                         xbee_rx, NULL);
 385         if (channel < 0) {
 386                 printf_P(PSTR("cannot send: no free channel\r\n"));
 387                 return -1;
 388         }
 389
 390         /* copy context in the static struct table (avoiding a malloc) */
 391         memcpy(&xbee_ctx[channel], ctx, sizeof(*ctx));
 392         ctx = &xbee_ctx[channel];
 393         xbee_set_opaque(xbee_dev, channel, ctx);
 394
 395         if (xbee_debug)
 396                 printf_P(PSTR("send frame channel=%d type=0x%x len=%d\r\n"),
 397                          channel, type, len);
 398         if (xbee_hexdump)
 399                 hexdump("xmit frame", buf, len);
 400
 401         /* transmit the frame on this channel */
 402         ret = xbee_proto_xmit(xbee_dev, channel, type, buf,
 403                               len);
 404         if (ret < 0) {
 405                 printf_P(PSTR("cannot send\r\n"));
 406                 xbee_unregister_channel(xbee_dev, channel);
 407                 return -1;
 408         }
 409
 410         ctx->channel = channel;
 411         xbee_load_timeout(ctx);   /* load a timeout event */
 412
 413         /* suspend command line until we have answer or timeout */
 414         if (foreground) {
 415                 ctx->foreground = 1;
 416                 rdline_stop(&xbeeboard.rdl); /* don't display prompt when return */
 417                 xbee_stdin_disable();  /* unload file descriptor polling */
 418         }
 419
 420         return 0;
 421 }
 422
 423 /* send an AT command with parameters filled by caller. Disable
 424  * command line until we get the answer or until a timeout occurs */
 425 int xbeeapp_send_atcmd(const char *atcmd_str,
 426                        void *param, unsigned param_len, int foreground,
 427                        int (*func)(void *frame, unsigned len, void *arg), void *arg)
 428 {
 429         struct xbee_ctx ctx;
 430         struct {
 431                 struct xbee_atcmd_hdr atcmd;
 432                 char buf[XBEE_MAX_FRAME_LEN];
 433         } __attribute__((packed)) frame;
 434
 435         memset(&ctx, 0, sizeof(ctx));
 436         ctx.atcmd_query[0] = atcmd_str[0];
 437         ctx.atcmd_query[1] = atcmd_str[1];
 438         ctx.func = func;
 439         ctx.arg = arg;
 440
 441         memcpy(&frame.atcmd.cmd, atcmd_str, 2);
 442         memcpy(&frame.buf, param, param_len);
 443
 444         if (xbeeapp_send(&ctx, XBEE_TYPE_ATCMD, &frame,
 445                          sizeof(struct xbee_atcmd_hdr) +
 446                          param_len, foreground) < 0) {
 447                 return -1;
 448         }
 449
 450         return 0;
 451 }
 452
 453 int xbeeapp_send_msg(uint64_t addr, void *data,
 454                      unsigned data_len, int foreground)
 455 {
 456         struct xbee_ctx ctx;
 457         struct {
 458                 struct xbee_xmit_hdr xmit;
 459                 char buf[XBEE_MAX_FRAME_LEN];
 460         } __attribute__((packed)) frame;
 461
 462         memset(&ctx, 0, sizeof(ctx));
 463         ctx.atcmd_query[0] = '\0';
 464
 465         frame.xmit.dstaddr = htonll(addr);
 466         frame.xmit.reserved = htons(0xFFFE);
 467         frame.xmit.bcast_radius = 0;
 468         frame.xmit.opts = 0;
 469         memcpy(&frame.buf, data, data_len);
 470
 471         if (xbeeapp_send(&ctx, XBEE_TYPE_XMIT, &frame,
 472                          sizeof(struct xbee_xmit_hdr) +
 473                          data_len, foreground) < 0) {
 474                 return -1;
 475         }
 476
 477         return 0;
 478 }
 479
 480 void xbee_stdin_enable(void)
 481 {
 482         xbee_cmdline_input_enabled = 1;
 483 }
 484
 485 void xbee_stdin_disable(void)
 486 {
 487         xbee_cmdline_input_enabled = 0;
 488 }
 489
 490 static void evt_timeout(struct callout_manager *cm, struct callout *clt,
 491                         void *arg)
 492 {
 493         struct xbee_ctx *ctx = arg;
 494
 495         (void)cm;
 496         (void)clt;
 497
 498         printf_P(PSTR("Timeout\r\n"));
 499
 500         /* restart command line */
 501         xbee_stdin_enable();
 502         rdline_newline(&xbeeboard.rdl, xbeeboard.prompt);
 503
 504         /* free event */
 505         xbee_unregister_channel(xbee_dev, ctx->channel);
 506 }
 507
 508 void xbee_load_timeout(struct xbee_ctx *ctx)
 509 {
 510         callout_reset(&cm, &ctx->timeout, TIMEOUT_MS, SINGLE, evt_timeout, ctx);
 511 }
 512
 513 void xbee_unload_timeout(struct xbee_ctx *ctx)
 514 {
 515         callout_stop(&cm, &ctx->timeout);
 516 }
 517
 518 void bootloader(void)
 519 {
 520 #define BOOTLOADER_ADDR 0x3f000
 521         if (pgm_read_byte_far(BOOTLOADER_ADDR) == 0xff) {
 522                 printf_P(PSTR("Bootloader is not present\r\n"));
 523                 return;
 524         }
 525         cli();
 526         /* ... very specific :( */
 527         TIMSK0 = 0;
 528         TIMSK1 = 0;
 529         TIMSK2 = 0;
 530         TIMSK3 = 0;
 531         EIMSK = 0;
 532         UCSR0B = 0;
 533         UCSR1B = 0;
 534         SPCR = 0;
 535         TWCR = 0;
 536         ACSR = 0;
 537         ADCSRA = 0;
 538
 539         /* XXX */
 540         /* __asm__ __volatile__ ("ldi r31,0xf8\n"); */
 541         /* __asm__ __volatile__ ("ldi r30,0x00\n"); */
 542         /* __asm__ __volatile__ ("eijmp\n"); */
 543 }
 544
 545 void xbee_mainloop(void)
 546 {
 547         while (1) {
 548                 callout_manage(&cm);
 549
 550                 if (xbee_raw) {
 551                         int16_t c;
 552
 553                         /* from xbee to cmdline */
 554                         c = xbee_dev_recv(NULL);
 555                         if (c >= 0)
 556                                 cmdline_dev_send((uint8_t)c, NULL);
 557
 558                         /* from cmdline to xbee */
 559                         c = cmdline_dev_recv(NULL);
 560                         if (c == 4) { /* CTRL-d */
 561                                 xbee_raw = 0;
 562                                 rdline_newline(&xbeeboard.rdl,
 563                                                xbeeboard.prompt);
 564                         }
 565                         else if (c >= 0) {
 566                                 /* send to xbee */
 567                                 xbee_dev_send((uint8_t)c, NULL);
 568
 569                                 /* echo on cmdline */
 570                                 cmdline_dev_send((uint8_t)c, NULL);
 571                         }
 572                 }
 573                 else {
 574                         if (xbee_cmdline_input_enabled)
 575                                 cmdline_poll();
 576                         xbee_proto_rx(xbee_dev);
 577                 }
 578         }
 579 }
 580
 581 /* return time in milliseconds on unsigned 16 bits */
 582 static uint16_t get_time_ms(void)
 583 {
 584         return global_ms;
 585 }
 586
 587 static void do_led_blink(struct callout_manager *cm,
 588                          struct callout *clt, void *dummy)
 589 {
 590         static uint8_t a = 0;
 591
 592         (void)cm;
 593         (void)clt;
 594         (void)dummy;
 595
 596         /* XXX */
 597         a++;
 598 }
 599
 600 static void increment_ms(void *dummy)
 601 {
 602         (void)dummy;
 603         global_ms++;
 604 }
 605
 606 static void main_timer_interrupt(void)
 607 {
 608         static uint8_t cpt = 0;
 609         cpt++;
 610         sei();
 611         if ((cpt & 0x3) == 0)
 612                 scheduler_interrupt();
 613 }
 614
 615 /** Main program entry point. This routine contains the overall program flow, including initial
 616  *  setup of all components and the main program loop.
 617  */
 618 int main(void)
 619 {
 620         struct callout t1;
 621         FILE *xbee_file;
 622         int8_t err;
 623         struct xbee_dev dev;
 624
 625         uart_init();
 626         uart_register_rx_event(CMDLINE_UART, emergency);
 627
 628         fdevopen(cmdline_dev_send, cmdline_dev_recv);
 629         xbee_file = fdevopen(xbee_dev_send, xbee_dev_recv);
 630         scheduler_init();
 631         timer_init();
 632         timer0_register_OV_intr(main_timer_interrupt);
 633
 634         scheduler_add_periodical_event_priority(increment_ms, NULL,
 635                                                 1000L / SCHEDULER_UNIT,
 636                                                 LED_PRIO);
 637         cmdline_init();
 638         spi_servo_init();
 639
 640         printf_P(PSTR("\r\n"));
 641         rdline_newline(&xbeeboard.rdl, xbeeboard.prompt);
 642
 643         callout_manager_init(&cm, get_time_ms);
 644         callout_reset(&cm, &t1, 500, PERIODICAL, do_led_blink, NULL);
 645
 646         /* initialize libxbee */
 647         err = xbee_init();
 648         if (err < 0)
 649                 return -1;
 650
 651         xbee_dev = &dev;
 652
 653         /* open xbee device */
 654         if (xbee_open(xbee_dev, xbee_file) < 0)
 655                 return -1;
 656
 657         /* register default channel with a callback */
 658         if (xbee_register_channel(xbee_dev, XBEE_DEFAULT_CHANNEL,
 659                                   xbee_rx, NULL) < 0) {
 660                 fprintf(stderr, "cannot register default channel\n");
 661                 return -1;
 662         }
 663
 664         sei();
 665         xbee_mainloop();
 666         return 0;
 667 }