src/hardware/brymen-bm86x/protocol.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2014 Aurelien Jacobs <aurel@gnuage.org>
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <config.h>
  21 #include <string.h>
  22 #include <math.h>
  23 #include "protocol.h"
  24
  25 #define USB_TIMEOUT 500
  26
  27 static const char char_map[128] = {
  28         [0x20] = '-',
  29         [0x5F] = '0',
  30         [0x50] = '1',
  31         [0x6D] = '2',
  32         [0x7C] = '3',
  33         [0x72] = '4',
  34         [0x3E] = '5',
  35         [0x3F] = '6',
  36         [0x54] = '7',
  37         [0x7F] = '8',
  38         [0x7E] = '9',
  39         [0x0F] = 'C',
  40         [0x27] = 'F',
  41         [0x0B] = 'L',
  42         [0x79] = 'd',
  43         [0x10] = 'i',
  44         [0x39] = 'o',
  45 };
  46
  47 static int brymen_bm86x_parse_digits(const unsigned char *buf, int length,
  48                                      char *str, float *floatval,
  49                                      char *temp_unit, int *digits, int flag)
  50 {
  51         char c, *p = str;
  52         int i, ret;
  53
  54         *digits = INT_MIN;
  55
  56         if (buf[0] & flag)
  57                 *p++ = '-';
  58         for (i = 0; i < length; i++) {
  59                 if (i && i < 5 && buf[i+1] & 0x01) {
  60                         *p++ = '.';
  61                         *digits = 0;
  62                 }
  63                 c = char_map[buf[i+1] >> 1];
  64                 if (i == 5 && (c == 'C' || c == 'F'))
  65                         *temp_unit = c;
  66                 else if (c) {
  67                         *p++ = c;
  68                         (*digits)++;
  69                 }
  70         }
  71         *p = 0;
  72
  73         if (*digits < 0)
  74                 *digits = 0;
  75
  76         if ((ret = sr_atof_ascii(str, floatval))) {
  77                 sr_dbg("invalid float string: '%s'", str);
  78                 return ret;
  79         }
  80
  81         return SR_OK;
  82 }
  83
  84 static void brymen_bm86x_parse(unsigned char *buf, float *floatval,
  85                                struct sr_datafeed_analog *analog)
  86 {
  87         char str[16], temp_unit;
  88         int ret1, ret2, digits[2], over_limit;
  89
  90         ret1 = brymen_bm86x_parse_digits(buf+2, 6, str, &floatval[0],
  91                                          &temp_unit, &digits[0], 0x80);
  92         over_limit = strstr(str, "0L") || strstr(str, "0.L");
  93         ret2 = brymen_bm86x_parse_digits(buf+9, 4, str, &floatval[1],
  94                                          &temp_unit, &digits[1], 0x10);
  95
  96         /* main display */
  97         if (ret1 == SR_OK || over_limit) {
  98                 /* SI unit */
  99                 if (buf[8] & 0x01) {
 100                         analog[0].meaning->mq = SR_MQ_VOLTAGE;
 101                         analog[0].meaning->unit = SR_UNIT_VOLT;
 102                         if (!strcmp(str, "diod")) {
 103                                 analog[0].meaning->mqflags |= SR_MQFLAG_DIODE;
 104                                 analog[0].meaning->mqflags |= SR_MQFLAG_DC;
 105                         }
 106                 } else if (buf[14] & 0x80) {
 107                         analog[0].meaning->mq = SR_MQ_CURRENT;
 108                         analog[0].meaning->unit = SR_UNIT_AMPERE;
 109                 } else if (buf[14] & 0x20) {
 110                         analog[0].meaning->mq = SR_MQ_CAPACITANCE;
 111                         analog[0].meaning->unit = SR_UNIT_FARAD;
 112                 } else if (buf[14] & 0x10) {
 113                         analog[0].meaning->mq = SR_MQ_CONDUCTANCE;
 114                         analog[0].meaning->unit = SR_UNIT_SIEMENS;
 115                 } else if (buf[15] & 0x01) {
 116                         analog[0].meaning->mq = SR_MQ_FREQUENCY;
 117                         analog[0].meaning->unit = SR_UNIT_HERTZ;
 118                 } else if (buf[10] & 0x01) {
 119                         analog[0].meaning->mq = SR_MQ_CONTINUITY;
 120                         analog[0].meaning->unit = SR_UNIT_OHM;
 121                 } else if (buf[15] & 0x10) {
 122                         analog[0].meaning->mq = SR_MQ_RESISTANCE;
 123                         analog[0].meaning->unit = SR_UNIT_OHM;
 124                 } else if (buf[15] & 0x02) {
 125                         analog[0].meaning->mq = SR_MQ_POWER;
 126                         analog[0].meaning->unit = SR_UNIT_DECIBEL_MW;
 127                 } else if (buf[15] & 0x80) {
 128                         analog[0].meaning->mq = SR_MQ_DUTY_CYCLE;
 129                         analog[0].meaning->unit = SR_UNIT_PERCENTAGE;
 130                 } else if (buf[ 2] & 0x0A) {
 131                         analog[0].meaning->mq = SR_MQ_TEMPERATURE;
 132                         if (temp_unit == 'F')
 133                                 analog[0].meaning->unit = SR_UNIT_FAHRENHEIT;
 134                         else
 135                                 analog[0].meaning->unit = SR_UNIT_CELSIUS;
 136                 }
 137
 138                 /* when MIN MAX and AVG are displayed at the same time, remove them */
 139                 if ((buf[1] & 0xE0) == 0xE0)
 140                         buf[1] &= ~0xE0;
 141
 142                 /* AC/DC/Auto flags */
 143                 if (buf[1] & 0x10)  analog[0].meaning->mqflags |= SR_MQFLAG_DC;
 144                 if (buf[2] & 0x01)  analog[0].meaning->mqflags |= SR_MQFLAG_AC;
 145                 if (buf[1] & 0x01)  analog[0].meaning->mqflags |= SR_MQFLAG_AUTORANGE;
 146                 if (buf[1] & 0x08)  analog[0].meaning->mqflags |= SR_MQFLAG_HOLD;
 147                 if (buf[1] & 0x20)  analog[0].meaning->mqflags |= SR_MQFLAG_MAX;
 148                 if (buf[1] & 0x40)  analog[0].meaning->mqflags |= SR_MQFLAG_MIN;
 149                 if (buf[1] & 0x80)  analog[0].meaning->mqflags |= SR_MQFLAG_AVG;
 150                 if (buf[3] & 0x01)  analog[0].meaning->mqflags |= SR_MQFLAG_RELATIVE;
 151
 152                 /* when dBm is displayed, remove the m suffix so that it is
 153                    not considered as the 10e-3 SI prefix */
 154                 if (buf[15] & 0x02)
 155                         buf[15] &= ~0x04;
 156
 157                 /* SI prefix */
 158                 if (buf[14] & 0x40)  { floatval[0] *= 1e-9; digits[0] += 9; } /* n */
 159                 if (buf[15] & 0x08)  { floatval[0] *= 1e-6; digits[0] += 6; } /* µ */
 160                 if (buf[15] & 0x04)  { floatval[0] *= 1e-3; digits[0] += 3; } /* m */
 161                 if (buf[15] & 0x40)  { floatval[0] *= 1e3;  digits[0] -= 3; } /* k */
 162                 if (buf[15] & 0x20)  { floatval[0] *= 1e6;  digits[0] -= 6; } /* M */
 163
 164                 if (over_limit)      floatval[0] = INFINITY;
 165
 166                 analog[0].encoding->digits  = digits[0];
 167                 analog[0].spec->spec_digits = digits[0];
 168         }
 169
 170         /* secondary display */
 171         if (ret2 == SR_OK) {
 172                 /* SI unit */
 173                 if (buf[14] & 0x08) {
 174                         analog[1].meaning->mq = SR_MQ_VOLTAGE;
 175                         analog[1].meaning->unit = SR_UNIT_VOLT;
 176                 } else if (buf[9] & 0x04) {
 177                         analog[1].meaning->mq = SR_MQ_CURRENT;
 178                         analog[1].meaning->unit = SR_UNIT_AMPERE;
 179                 } else if (buf[9] & 0x08) {
 180                         analog[1].meaning->mq = SR_MQ_CURRENT;
 181                         analog[1].meaning->unit = SR_UNIT_PERCENTAGE;
 182                 } else if (buf[14] & 0x04) {
 183                         analog[1].meaning->mq = SR_MQ_FREQUENCY;
 184                         analog[1].meaning->unit = SR_UNIT_HERTZ;
 185                 } else if (buf[9] & 0x40) {
 186                         analog[1].meaning->mq = SR_MQ_TEMPERATURE;
 187                         if (temp_unit == 'F')
 188                                 analog[1].meaning->unit = SR_UNIT_FAHRENHEIT;
 189                         else
 190                                 analog[1].meaning->unit = SR_UNIT_CELSIUS;
 191                 }
 192
 193                 /* AC flag */
 194                 if (buf[9] & 0x20)  analog[1].meaning->mqflags |= SR_MQFLAG_AC;
 195
 196                 /* SI prefix */
 197                 if (buf[ 9] & 0x01)  { floatval[1] *= 1e-6; digits[1] += 6; } /* µ */
 198                 if (buf[ 9] & 0x02)  { floatval[1] *= 1e-3; digits[1] += 3; } /* m */
 199                 if (buf[14] & 0x02)  { floatval[1] *= 1e3;  digits[1] -= 3; } /* k */
 200                 if (buf[14] & 0x01)  { floatval[1] *= 1e6;  digits[1] -= 6; } /* M */
 201
 202                 analog[1].encoding->digits  = digits[1];
 203                 analog[1].spec->spec_digits = digits[1];
 204         }
 205
 206         if (buf[9] & 0x80)
 207                 sr_spew("Battery is low.");
 208 }
 209
 210 static void brymen_bm86x_handle_packet(const struct sr_dev_inst *sdi,
 211                                        unsigned char *buf)
 212 {
 213         struct dev_context *devc;
 214         struct sr_datafeed_packet packet;
 215         struct sr_datafeed_analog analog[2];
 216         struct sr_analog_encoding encoding[2];
 217         struct sr_analog_meaning meaning[2];
 218         struct sr_analog_spec spec[2];
 219         struct sr_channel *channel;
 220         int sent_ch1, sent_ch2;
 221         float floatval[2];
 222
 223         devc = sdi->priv;
 224
 225         /* Note: digits/spec_digits will be overridden later. */
 226         sr_analog_init(&analog[0], &encoding[0], &meaning[0], &spec[0], 0);
 227         sr_analog_init(&analog[1], &encoding[1], &meaning[1], &spec[1], 0);
 228
 229         brymen_bm86x_parse(buf, floatval, analog);
 230         sent_ch1 = sent_ch2 = 0;
 231
 232         channel = sdi->channels->data;
 233         if (analog[0].meaning->mq != 0 && channel->enabled) {
 234                 /* Got a measurement. */
 235                 sent_ch1 = 1;
 236                 analog[0].num_samples = 1;
 237                 analog[0].data = &floatval[0];
 238                 analog[0].meaning->channels = g_slist_append(NULL, channel);
 239                 packet.type = SR_DF_ANALOG;
 240                 packet.payload = &analog[0];
 241                 sr_session_send(sdi, &packet);
 242                 g_slist_free(analog[0].meaning->channels);
 243         }
 244
 245         channel = sdi->channels->next->data;
 246         if (analog[1].meaning->mq != 0 && channel->enabled) {
 247                 /* Got a measurement. */
 248                 sent_ch2 = 1;
 249                 analog[1].num_samples = 1;
 250                 analog[1].data = &floatval[1];
 251                 analog[1].meaning->channels = g_slist_append(NULL, channel);
 252                 packet.type = SR_DF_ANALOG;
 253                 packet.payload = &analog[1];
 254                 sr_session_send(sdi, &packet);
 255                 g_slist_free(analog[1].meaning->channels);
 256         }
 257
 258         if (sent_ch1 || sent_ch2)
 259                 sr_sw_limits_update_samples_read(&devc->sw_limits, 1);
 260 }
 261
 262 static int brymen_bm86x_send_command(const struct sr_dev_inst *sdi)
 263 {
 264         struct sr_usb_dev_inst *usb;
 265         unsigned char buf[] = { 0x00, 0x86, 0x66 };
 266         int ret;
 267
 268         usb = sdi->conn;
 269
 270         sr_dbg("Sending HID set report.");
 271         ret = libusb_control_transfer(usb->devhdl,
 272                                       LIBUSB_REQUEST_TYPE_CLASS |
 273                                       LIBUSB_RECIPIENT_INTERFACE |
 274                                       LIBUSB_ENDPOINT_OUT,
 275                                       9,     /* bRequest: HID set_report */
 276                                       0x300, /* wValue: HID feature, report num 0 */
 277                                       0,     /* wIndex: interface 0 */
 278                                       buf, sizeof(buf), USB_TIMEOUT);
 279
 280         if (ret < 0) {
 281                 sr_err("HID feature report error: %s.", libusb_error_name(ret));
 282                 return SR_ERR;
 283         }
 284
 285         if (ret != sizeof(buf)) {
 286                 sr_err("Short packet: sent %d/%zu bytes.", ret, sizeof(buf));
 287                 return SR_ERR;
 288         }
 289
 290         return SR_OK;
 291 }
 292
 293 static int brymen_bm86x_read_interrupt(const struct sr_dev_inst *sdi)
 294 {
 295         struct dev_context *devc;
 296         struct sr_usb_dev_inst *usb;
 297         unsigned char buf[24];
 298         int ret, transferred;
 299
 300         devc = sdi->priv;
 301         usb = sdi->conn;
 302
 303         sr_dbg("Reading HID interrupt report.");
 304         /* Get data from EP1 using an interrupt transfer. */
 305         ret = libusb_interrupt_transfer(usb->devhdl,
 306                                         LIBUSB_ENDPOINT_IN | 1, /* EP1, IN */
 307                                         buf, sizeof(buf),
 308                                         &transferred, USB_TIMEOUT);
 309
 310         if (ret == LIBUSB_ERROR_TIMEOUT) {
 311                 if (++devc->interrupt_pending > 3)
 312                         devc->interrupt_pending = 0;
 313                 return SR_OK;
 314         }
 315
 316         if (ret < 0) {
 317                 sr_err("USB receive error: %s.", libusb_error_name(ret));
 318                 return SR_ERR;
 319         }
 320
 321         if (transferred != sizeof(buf)) {
 322                 sr_err("Short packet: received %d/%zu bytes.", transferred, sizeof(buf));
 323                 return SR_ERR;
 324         }
 325
 326         devc->interrupt_pending = 0;
 327         brymen_bm86x_handle_packet(sdi, buf);
 328
 329         return SR_OK;
 330 }
 331
 332 SR_PRIV int brymen_bm86x_receive_data(int fd, int revents, void *cb_data)
 333 {
 334         struct sr_dev_inst *sdi;
 335         struct dev_context *devc;
 336
 337         (void)fd;
 338         (void)revents;
 339
 340         if (!(sdi = cb_data))
 341                 return TRUE;
 342
 343         if (!(devc = sdi->priv))
 344                 return TRUE;
 345
 346         if (!devc->interrupt_pending) {
 347                 if (brymen_bm86x_send_command(sdi))
 348                         return FALSE;
 349                 devc->interrupt_pending = 1;
 350         }
 351
 352         if (brymen_bm86x_read_interrupt(sdi))
 353                 return FALSE;
 354
 355         if (sr_sw_limits_check(&devc->sw_limits))
 356                 sr_dev_acquisition_stop(sdi);
 357
 358         return TRUE;
 359 }