src/hardware/scpi-dmm/api.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2018 Gerhard Sittig <gerhard.sittig@gmx.net>
   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 <string.h>
  21 #include "protocol.h"
  22
  23 static struct sr_dev_driver scpi_dmm_driver_info;
  24
  25 static const uint32_t scanopts[] = {
  26         SR_CONF_CONN,
  27         SR_CONF_SERIALCOMM,
  28 };
  29
  30 static const uint32_t drvopts[] = {
  31         SR_CONF_MULTIMETER,
  32 };
  33
  34 static const uint32_t devopts_generic[] = {
  35         SR_CONF_CONTINUOUS,
  36         SR_CONF_LIMIT_SAMPLES | SR_CONF_GET | SR_CONF_SET,
  37         SR_CONF_LIMIT_MSEC | SR_CONF_GET | SR_CONF_SET,
  38         SR_CONF_MEASURED_QUANTITY | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
  39 };
  40
  41 static const struct scpi_command cmdset_agilent[] = {
  42         { DMM_CMD_SETUP_REMOTE, "\n", },
  43         { DMM_CMD_SETUP_FUNC, "CONF:%s", },
  44         { DMM_CMD_QUERY_FUNC, "CONF?", },
  45         { DMM_CMD_START_ACQ, "MEAS", },
  46         { DMM_CMD_STOP_ACQ, "ABORT", },
  47         { DMM_CMD_QUERY_VALUE, "READ?", },
  48         { DMM_CMD_QUERY_PREC, "CONF?", },
  49         ALL_ZERO,
  50 };
  51
  52 /*
  53  * cmdset_hp is used for the 34401A, which was added to this code after the
  54  * 34405A and 34465A. It differs in starting the measurement with INIT: using
  55  * MEAS without a trailing '?' (as used for the 34405A) is not valid for the
  56  * 34401A and gives an error.
  57  * I'm surprised the same instruction sequence doesn't work and INIT may
  58  * work for both, but I don't have the others to re-test.
  59  *
  60  * cmdset_hp also works well for the 34410A, using cmdset_agilent throws an
  61  * error on 'MEAS' without a '?'.
  62  *
  63  * On the 34401A,
  64  *  MEAS <optional parameters> ? configures, arms, triggers and waits
  65  *       for a reading
  66  *  CONF <parameters> configures
  67  *  INIT prepares for triggering (trigger mode is not set, assumed
  68  *       internal - external might time out)
  69  *  *OPC waits for completion, and
  70  *  READ? retrieves the result
  71  */
  72 static const struct scpi_command cmdset_hp[] = {
  73         { DMM_CMD_SETUP_REMOTE, "\n", },
  74         { DMM_CMD_SETUP_FUNC, "CONF:%s", },
  75         { DMM_CMD_QUERY_FUNC, "CONF?", },
  76         { DMM_CMD_START_ACQ, "INIT", },
  77         { DMM_CMD_STOP_ACQ, "ABORT", },
  78         { DMM_CMD_QUERY_VALUE, "READ?", },
  79         { DMM_CMD_QUERY_PREC, "CONF?", },
  80         ALL_ZERO,
  81 };
  82
  83 static const struct scpi_command cmdset_gwinstek[] = {
  84         { DMM_CMD_SETUP_REMOTE, "SYST:REM", },
  85         { DMM_CMD_SETUP_FUNC, "CONF:%s", },
  86         { DMM_CMD_QUERY_FUNC, "CONF:STAT:FUNC?", },
  87         { DMM_CMD_START_ACQ, "*CLS;SYST:REM", },
  88         { DMM_CMD_STOP_ACQ, "SYST:LOC", },
  89         { DMM_CMD_QUERY_VALUE, "VAL1?", },
  90         { DMM_CMD_QUERY_PREC, "SENS:DET:RATE?", },
  91         ALL_ZERO,
  92 };
  93
  94 static const struct scpi_command cmdset_gwinstek_906x[] = {
  95         { DMM_CMD_SETUP_REMOTE, "SYST:REM", },
  96         { DMM_CMD_SETUP_FUNC, "CONF:%s", },
  97         { DMM_CMD_QUERY_FUNC, "CONF?", },
  98         { DMM_CMD_START_ACQ, "*CLS;SYST:REM", },
  99         { DMM_CMD_STOP_ACQ, "SYST:LOC", },
 100         { DMM_CMD_QUERY_VALUE, "VAL1?", },
 101         { DMM_CMD_QUERY_PREC, "SENS:DET:RATE?", },
 102         ALL_ZERO,
 103 };
 104
 105 static const struct mqopt_item mqopts_agilent_34405a[] = {
 106         { SR_MQ_VOLTAGE, SR_MQFLAG_DC, "VOLT:DC", "VOLT ", NO_DFLT_PREC, },
 107         { SR_MQ_VOLTAGE, SR_MQFLAG_AC, "VOLT:AC", "VOLT:AC ", NO_DFLT_PREC, },
 108         { SR_MQ_CURRENT, SR_MQFLAG_DC, "CURR:DC", "CURR ", NO_DFLT_PREC, },
 109         { SR_MQ_CURRENT, SR_MQFLAG_AC, "CURR:AC", "CURR:AC ", NO_DFLT_PREC, },
 110         { SR_MQ_RESISTANCE, 0, "RES", "RES ", NO_DFLT_PREC, },
 111         { SR_MQ_CONTINUITY, 0, "CONT", "CONT", -1, },
 112         { SR_MQ_CAPACITANCE, 0, "CAP", "CAP ", NO_DFLT_PREC, },
 113         { SR_MQ_VOLTAGE, SR_MQFLAG_DC | SR_MQFLAG_DIODE, "DIOD", "DIOD", -4, },
 114         { SR_MQ_TEMPERATURE, 0, "TEMP", "TEMP ", NO_DFLT_PREC, },
 115         { SR_MQ_FREQUENCY, 0, "FREQ", "FREQ ", NO_DFLT_PREC, },
 116 };
 117
 118 static const struct mqopt_item mqopts_agilent_34401a[] = {
 119         { SR_MQ_VOLTAGE, SR_MQFLAG_DC, "VOLT:DC", "VOLT ", NO_DFLT_PREC, },
 120         { SR_MQ_VOLTAGE, SR_MQFLAG_AC, "VOLT:AC", "VOLT:AC ", NO_DFLT_PREC, },
 121         { SR_MQ_CURRENT, SR_MQFLAG_DC, "CURR:DC", "CURR ", NO_DFLT_PREC, },
 122         { SR_MQ_CURRENT, SR_MQFLAG_AC, "CURR:AC", "CURR:AC ", NO_DFLT_PREC, },
 123         { SR_MQ_RESISTANCE, 0, "RES", "RES ", NO_DFLT_PREC, },
 124         { SR_MQ_RESISTANCE, SR_MQFLAG_FOUR_WIRE, "FRES", "FRES ", NO_DFLT_PREC, },
 125         { SR_MQ_CONTINUITY, 0, "CONT", "CONT", -1, },
 126         { SR_MQ_VOLTAGE, SR_MQFLAG_DC | SR_MQFLAG_DIODE, "DIOD", "DIOD", -4, },
 127         { SR_MQ_FREQUENCY, 0, "FREQ", "FREQ ", NO_DFLT_PREC, },
 128         { SR_MQ_TIME, 0, "PER", "PER ", NO_DFLT_PREC, },
 129 };
 130
 131 static const struct mqopt_item mqopts_gwinstek_gdm8200a[] = {
 132         { SR_MQ_VOLTAGE, SR_MQFLAG_DC, "VOLT:DC", "01", NO_DFLT_PREC, },
 133         { SR_MQ_VOLTAGE, SR_MQFLAG_AC, "VOLT:AC", "02", NO_DFLT_PREC, },
 134         { SR_MQ_CURRENT, SR_MQFLAG_DC, "CURR:DC", "03", NO_DFLT_PREC, },
 135         { SR_MQ_CURRENT, SR_MQFLAG_AC, "CURR:AC", "04", NO_DFLT_PREC, },
 136         { SR_MQ_CURRENT, SR_MQFLAG_DC, "CURR:DC", "05", NO_DFLT_PREC, }, /* mA */
 137         { SR_MQ_CURRENT, SR_MQFLAG_AC, "CURR:AC", "06", NO_DFLT_PREC, }, /* mA */
 138         { SR_MQ_RESISTANCE, 0, "RES", "07", NO_DFLT_PREC, },
 139         { SR_MQ_RESISTANCE, SR_MQFLAG_FOUR_WIRE, "FRES", "16", NO_DFLT_PREC, },
 140         { SR_MQ_CONTINUITY, 0, "CONT", "13", -1, },
 141         { SR_MQ_VOLTAGE, SR_MQFLAG_DC | SR_MQFLAG_DIODE, "DIOD", "17", -4, },
 142         { SR_MQ_TEMPERATURE, 0, "TEMP", "09", NO_DFLT_PREC, }, /* Celsius */
 143         { SR_MQ_TEMPERATURE, 0, "TEMP", "15", NO_DFLT_PREC, }, /* Fahrenheit */
 144         { SR_MQ_FREQUENCY, 0, "FREQ", "08", NO_DFLT_PREC, },
 145         { SR_MQ_TIME, 0, "PER", "14", NO_DFLT_PREC, },
 146 };
 147
 148 static const struct mqopt_item mqopts_gwinstek_gdm906x[] = {
 149         { SR_MQ_VOLTAGE, SR_MQFLAG_DC, "VOLT:DC", "VOLT ", NO_DFLT_PREC, },
 150         { SR_MQ_VOLTAGE, SR_MQFLAG_AC, "VOLT:AC", "VOLT:AC", NO_DFLT_PREC, },
 151         { SR_MQ_CURRENT, SR_MQFLAG_DC, "CURR:DC", "CURR ", NO_DFLT_PREC, },
 152         { SR_MQ_CURRENT, SR_MQFLAG_AC, "CURR:AC", "CURR:AC", NO_DFLT_PREC, },
 153         { SR_MQ_RESISTANCE, 0, "RES", "RES", NO_DFLT_PREC, },
 154         { SR_MQ_RESISTANCE, SR_MQFLAG_FOUR_WIRE, "FRES", "FRES", NO_DFLT_PREC, },
 155         { SR_MQ_CONTINUITY, 0, "CONT", "CONT", -1, },
 156         { SR_MQ_VOLTAGE, SR_MQFLAG_DC | SR_MQFLAG_DIODE, "DIOD", "DIOD", -4, },
 157         { SR_MQ_TEMPERATURE, 0, "TEMP", "TEMP", NO_DFLT_PREC, },
 158         { SR_MQ_FREQUENCY, 0, "FREQ", "FREQ", NO_DFLT_PREC, },
 159         { SR_MQ_TIME, 0, "PER", "PER", NO_DFLT_PREC, },
 160         { SR_MQ_CAPACITANCE, 0, "CAP", "CAP", NO_DFLT_PREC, },
 161 };
 162
 163 SR_PRIV const struct scpi_dmm_model models[] = {
 164         {
 165                 "Agilent", "34405A",
 166                 1, 5, cmdset_agilent, ARRAY_AND_SIZE(mqopts_agilent_34405a),
 167                 scpi_dmm_get_meas_agilent,
 168                 ARRAY_AND_SIZE(devopts_generic),
 169                 0,
 170         },
 171         {
 172                 "Agilent", "34410A",
 173                 1, 6, cmdset_hp, ARRAY_AND_SIZE(mqopts_agilent_34405a),
 174                 scpi_dmm_get_meas_agilent,
 175                 ARRAY_AND_SIZE(devopts_generic),
 176                 0,
 177         },
 178         {
 179                 "GW", "GDM8251A",
 180                 1, 6, cmdset_gwinstek, ARRAY_AND_SIZE(mqopts_gwinstek_gdm8200a),
 181                 scpi_dmm_get_meas_gwinstek,
 182                 ARRAY_AND_SIZE(devopts_generic),
 183                 1000 * 2500,
 184         },
 185         {
 186                 "GW", "GDM8255A",
 187                 1, 6, cmdset_gwinstek, ARRAY_AND_SIZE(mqopts_gwinstek_gdm8200a),
 188                 scpi_dmm_get_meas_gwinstek,
 189                 ARRAY_AND_SIZE(devopts_generic),
 190                 1000 * 2500,
 191         },
 192         {
 193                 "GWInstek", "GDM9060",
 194                 1, 6, cmdset_gwinstek_906x, ARRAY_AND_SIZE(mqopts_gwinstek_gdm906x),
 195                 scpi_dmm_get_meas_agilent,
 196                 ARRAY_AND_SIZE(devopts_generic),
 197                 0,
 198         },
 199         {
 200                 "GWInstek", "GDM9061",
 201                 1, 6, cmdset_gwinstek_906x, ARRAY_AND_SIZE(mqopts_gwinstek_gdm906x),
 202                 scpi_dmm_get_meas_agilent,
 203                 ARRAY_AND_SIZE(devopts_generic),
 204                 0,
 205         },
 206         {
 207                 "HP", "34401A",
 208                 1, 6, cmdset_hp, ARRAY_AND_SIZE(mqopts_agilent_34401a),
 209                 scpi_dmm_get_meas_agilent,
 210                 ARRAY_AND_SIZE(devopts_generic),
 211                 /* 34401A: typ. 1020ms for AC readings (default is 1000ms). */
 212                 1000 * 1500,
 213         },
 214         {
 215                 "Keysight", "34465A",
 216                 1, 5, cmdset_agilent, ARRAY_AND_SIZE(mqopts_agilent_34405a),
 217                 scpi_dmm_get_meas_agilent,
 218                 ARRAY_AND_SIZE(devopts_generic),
 219                 0,
 220         },
 221 };
 222
 223 static const struct scpi_dmm_model *is_compatible(const char *vendor, const char *model)
 224 {
 225         size_t i;
 226         const struct scpi_dmm_model *entry;
 227
 228         for (i = 0; i < ARRAY_SIZE(models); i++) {
 229                 entry = &models[i];
 230                 if (!entry->vendor || !entry->model)
 231                         continue;
 232                 if (strcmp(vendor, entry->vendor) != 0)
 233                         continue;
 234                 if (strcmp(model, entry->model) != 0)
 235                         continue;
 236                 return entry;
 237         }
 238
 239         return NULL;
 240 }
 241
 242 static struct sr_dev_inst *probe_device(struct sr_scpi_dev_inst *scpi)
 243 {
 244         struct sr_scpi_hw_info *hw_info;
 245         int ret;
 246         const char *vendor;
 247         const struct scpi_dmm_model *model;
 248         struct sr_dev_inst *sdi;
 249         struct dev_context *devc;
 250         size_t i;
 251         gchar *channel_name;
 252
 253         scpi_dmm_cmd_delay(scpi);
 254         ret = sr_scpi_get_hw_id(scpi, &hw_info);
 255         if (ret != SR_OK) {
 256                 sr_info("Could not get IDN response.");
 257                 return NULL;
 258         }
 259         vendor = sr_vendor_alias(hw_info->manufacturer);
 260         model = is_compatible(vendor, hw_info->model);
 261         if (!model) {
 262                 sr_scpi_hw_info_free(hw_info);
 263                 return NULL;
 264         }
 265
 266         sdi = g_malloc0(sizeof(*sdi));
 267         sdi->vendor = g_strdup(hw_info->manufacturer);
 268         sdi->model = g_strdup(hw_info->model);
 269         sdi->version = g_strdup(hw_info->firmware_version);
 270         sdi->serial_num = g_strdup(hw_info->serial_number);
 271         sdi->conn = scpi;
 272         sdi->driver = &scpi_dmm_driver_info;
 273         sdi->inst_type = SR_INST_SCPI;
 274         sr_scpi_hw_info_free(hw_info);
 275         if (model->read_timeout_us)  /* non-default read timeout */
 276                 scpi->read_timeout_us = model->read_timeout_us;
 277         devc = g_malloc0(sizeof(*devc));
 278         sdi->priv = devc;
 279         devc->num_channels = model->num_channels;
 280         devc->cmdset = model->cmdset;
 281         devc->model = model;
 282
 283         for (i = 0; i < devc->num_channels; i++) {
 284                 channel_name = g_strdup_printf("P%zu", i + 1);
 285                 sr_channel_new(sdi, 0, SR_CHANNEL_ANALOG, TRUE, channel_name);
 286         }
 287
 288         return sdi;
 289 }
 290
 291 static GSList *scan(struct sr_dev_driver *di, GSList *options)
 292 {
 293         return sr_scpi_scan(di->context, options, probe_device);
 294 }
 295
 296 static int dev_open(struct sr_dev_inst *sdi)
 297 {
 298         struct sr_scpi_dev_inst *scpi;
 299         int ret;
 300
 301         scpi = sdi->conn;
 302         ret = sr_scpi_open(scpi);
 303         if (ret < 0) {
 304                 sr_err("Failed to open SCPI device: %s.", sr_strerror(ret));
 305                 return SR_ERR;
 306         }
 307
 308         return SR_OK;
 309 }
 310
 311 static int dev_close(struct sr_dev_inst *sdi)
 312 {
 313         struct sr_scpi_dev_inst *scpi;
 314
 315         scpi = sdi->conn;
 316         if (!scpi)
 317                 return SR_ERR_BUG;
 318
 319         sr_dbg("DIAG: sdi->status %d.", sdi->status - SR_ST_NOT_FOUND);
 320         if (sdi->status <= SR_ST_INACTIVE)
 321                 return SR_OK;
 322
 323         return sr_scpi_close(scpi);
 324 }
 325
 326 static int config_get(uint32_t key, GVariant **data,
 327         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 328 {
 329         struct dev_context *devc;
 330         enum sr_mq mq;
 331         enum sr_mqflag mqflag;
 332         GVariant *arr[2];
 333         int ret;
 334
 335         (void)cg;
 336
 337         devc = sdi->priv;
 338
 339         switch (key) {
 340         case SR_CONF_LIMIT_SAMPLES:
 341         case SR_CONF_LIMIT_MSEC:
 342                 return sr_sw_limits_config_get(&devc->limits, key, data);
 343         case SR_CONF_MEASURED_QUANTITY:
 344                 ret = scpi_dmm_get_mq(sdi, &mq, &mqflag, NULL, NULL);
 345                 if (ret != SR_OK)
 346                         return ret;
 347                 arr[0] = g_variant_new_uint32(mq);
 348                 arr[1] = g_variant_new_uint64(mqflag);
 349                 *data = g_variant_new_tuple(arr, ARRAY_SIZE(arr));
 350                 return SR_OK;
 351         default:
 352                 return SR_ERR_NA;
 353         }
 354 }
 355
 356 static int config_set(uint32_t key, GVariant *data,
 357         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 358 {
 359         struct dev_context *devc;
 360         enum sr_mq mq;
 361         enum sr_mqflag mqflag;
 362         GVariant *tuple_child;
 363
 364         (void)cg;
 365
 366         devc = sdi->priv;
 367
 368         switch (key) {
 369         case SR_CONF_LIMIT_SAMPLES:
 370         case SR_CONF_LIMIT_MSEC:
 371                 return sr_sw_limits_config_set(&devc->limits, key, data);
 372         case SR_CONF_MEASURED_QUANTITY:
 373                 tuple_child = g_variant_get_child_value(data, 0);
 374                 mq = g_variant_get_uint32(tuple_child);
 375                 g_variant_unref(tuple_child);
 376                 tuple_child = g_variant_get_child_value(data, 1);
 377                 mqflag = g_variant_get_uint64(tuple_child);
 378                 g_variant_unref(tuple_child);
 379                 return scpi_dmm_set_mq(sdi, mq, mqflag);
 380         default:
 381                 return SR_ERR_NA;
 382         }
 383 }
 384
 385 static int config_list(uint32_t key, GVariant **data,
 386         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 387 {
 388         struct dev_context *devc;
 389         GVariant *gvar, *arr[2];
 390         GVariantBuilder gvb;
 391         size_t i;
 392
 393         (void)cg;
 394
 395         devc = sdi ? sdi->priv : NULL;
 396
 397         switch (key) {
 398         case SR_CONF_SCAN_OPTIONS:
 399         case SR_CONF_DEVICE_OPTIONS:
 400                 if (!devc)
 401                         return STD_CONFIG_LIST(key, data, sdi, cg,
 402                                 scanopts, drvopts, devopts_generic);
 403                 return std_opts_config_list(key, data, sdi, cg,
 404                         ARRAY_AND_SIZE(scanopts), ARRAY_AND_SIZE(drvopts),
 405                         devc->model->devopts, devc->model->devopts_size);
 406         case SR_CONF_MEASURED_QUANTITY:
 407                 /* TODO Use std_gvar_measured_quantities() when available. */
 408                 if (!devc)
 409                         return SR_ERR_ARG;
 410                 g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
 411                 for (i = 0; i < devc->model->mqopt_size; i++) {
 412                         arr[0] = g_variant_new_uint32(devc->model->mqopts[i].mq);
 413                         arr[1] = g_variant_new_uint64(devc->model->mqopts[i].mqflag);
 414                         gvar = g_variant_new_tuple(arr, ARRAY_SIZE(arr));
 415                         g_variant_builder_add_value(&gvb, gvar);
 416                 }
 417                 *data = g_variant_builder_end(&gvb);
 418                 return SR_OK;
 419         default:
 420                 (void)devc;
 421                 return SR_ERR_NA;
 422         }
 423 }
 424
 425 static int dev_acquisition_start(const struct sr_dev_inst *sdi)
 426 {
 427         struct sr_scpi_dev_inst *scpi;
 428         struct dev_context *devc;
 429         int ret;
 430         const struct mqopt_item *item;
 431         const char *command;
 432         char *response;
 433
 434         scpi = sdi->conn;
 435         devc = sdi->priv;
 436
 437         ret = scpi_dmm_get_mq(sdi, &devc->start_acq_mq.curr_mq,
 438                 &devc->start_acq_mq.curr_mqflag, NULL, &item);
 439         if (ret != SR_OK)
 440                 return ret;
 441
 442         /*
 443          * Query for current precision if DMM supports the command
 444          */
 445         command = sr_scpi_cmd_get(devc->cmdset, DMM_CMD_QUERY_PREC);
 446         if (command && *command) {
 447                 scpi_dmm_cmd_delay(scpi);
 448                 ret = sr_scpi_get_string(scpi, command, &response);
 449                 if (ret == SR_OK) {
 450                         g_strstrip(response);
 451                         g_free(devc->precision);
 452                         devc->precision = g_strdup(response);
 453                         g_free(response);
 454                         sr_dbg("%s: Precision: '%s'", __func__, devc->precision);
 455                 } else {
 456                         sr_info("Precision query ('%s') failed: %d",
 457                                 command, ret);
 458                 }
 459         }
 460
 461         command = sr_scpi_cmd_get(devc->cmdset, DMM_CMD_START_ACQ);
 462         if (command && *command) {
 463                 scpi_dmm_cmd_delay(scpi);
 464                 ret = sr_scpi_send(scpi, command);
 465                 if (ret != SR_OK)
 466                         return ret;
 467         }
 468
 469         sr_sw_limits_acquisition_start(&devc->limits);
 470         ret = std_session_send_df_header(sdi);
 471         if (ret != SR_OK)
 472                 return ret;
 473
 474         ret = sr_scpi_source_add(sdi->session, scpi, G_IO_IN, 10,
 475                 scpi_dmm_receive_data, (void *)sdi);
 476         if (ret != SR_OK)
 477                 return ret;
 478
 479         return SR_OK;
 480 }
 481
 482 static int dev_acquisition_stop(struct sr_dev_inst *sdi)
 483 {
 484         struct sr_scpi_dev_inst *scpi;
 485         struct dev_context *devc;
 486         const char *command;
 487
 488         scpi = sdi->conn;
 489         devc = sdi->priv;
 490
 491         command = sr_scpi_cmd_get(devc->cmdset, DMM_CMD_STOP_ACQ);
 492         if (command && *command) {
 493                 scpi_dmm_cmd_delay(scpi);
 494                 (void)sr_scpi_send(scpi, command);
 495         }
 496         sr_scpi_source_remove(sdi->session, scpi);
 497
 498         std_session_send_df_end(sdi);
 499
 500         g_free(devc->precision);
 501         devc->precision = NULL;
 502
 503         return SR_OK;
 504 }
 505
 506 static struct sr_dev_driver scpi_dmm_driver_info = {
 507         .name = "scpi-dmm",
 508         .longname = "SCPI DMM",
 509         .api_version = 1,
 510         .init = std_init,
 511         .cleanup = std_cleanup,
 512         .scan = scan,
 513         .dev_list = std_dev_list,
 514         .dev_clear = std_dev_clear,
 515         .config_get = config_get,
 516         .config_set = config_set,
 517         .config_list = config_list,
 518         .dev_open = dev_open,
 519         .dev_close = dev_close,
 520         .dev_acquisition_start = dev_acquisition_start,
 521         .dev_acquisition_stop = dev_acquisition_stop,
 522         .context = NULL,
 523 };
 524 SR_REGISTER_DEV_DRIVER(scpi_dmm_driver_info);