2 * This file is part of the libsigrok project.
4 * Copyright (C) 2016 Alexandru Gagniuc <mr.nuke.me@gmail.com>
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.
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.
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/>.
25 static int set_mq_volt(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags);
26 static int set_mq_amp(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags);
27 static int set_mq_ohm(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags);
29 * The source for the frequency measurement can be either AC voltage, AC+DC
30 * voltage, AC current, or AC+DC current. Configuring this is not yet
31 * supported. For details, see "FSOURCE" command.
32 * The set_mode function is optional and can be set to NULL, but in that case
33 * a cmd string must be provided.
39 int (*set_mode)(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags);
40 } sr_mq_to_cmd_map[] = {
41 { SR_MQ_VOLTAGE, SR_UNIT_VOLT, "DCV", set_mq_volt },
42 { SR_MQ_CURRENT, SR_UNIT_AMPERE, "DCI", set_mq_amp },
43 { SR_MQ_RESISTANCE, SR_UNIT_OHM, "OHM", set_mq_ohm },
44 { SR_MQ_FREQUENCY, SR_UNIT_HERTZ, "FREQ", NULL },
47 static const struct rear_card_info rear_card_parameters[] = {
49 .type = REAR_TERMINALS,
51 .name = "Rear terminals",
56 .name = "44491A Armature Relay Multiplexer",
61 .name = "44492A Reed Relay Multiplexer",
66 static int send_mq_ac_dc(struct sr_scpi_dev_inst *scpi, const char *mode,
69 const char *ac_flag, *dc_flag;
71 if (flags & ~(SR_MQFLAG_AC | SR_MQFLAG_DC))
74 ac_flag = (flags & SR_MQFLAG_AC) ? "AC" : "";
76 /* Must specify DC measurement when AC flag is not given. */
77 if ((flags & SR_MQFLAG_DC) || !(flags & SR_MQFLAG_AC))
80 return sr_scpi_send(scpi, "%s%s%s", ac_flag, dc_flag, mode);
83 static int set_mq_volt(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags)
85 return send_mq_ac_dc(scpi, "V", flags);
88 static int set_mq_amp(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags)
90 return send_mq_ac_dc(scpi, "I", flags);
93 static int set_mq_ohm(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags)
97 if (flags & ~(SR_MQFLAG_FOUR_WIRE))
100 ohm_flag = (flags & SR_MQFLAG_FOUR_WIRE) ? "F" : "";
101 return sr_scpi_send(scpi, "OHM%s", ohm_flag);
104 SR_PRIV int hp_3457a_set_mq(const struct sr_dev_inst *sdi, enum sr_mq mq,
105 enum sr_mqflag mq_flags)
109 struct sr_scpi_dev_inst *scpi = sdi->conn;
110 struct dev_context *devc = sdi->priv;
112 for (i = 0; i < ARRAY_SIZE(sr_mq_to_cmd_map); i++) {
113 if (sr_mq_to_cmd_map[i].mq != mq)
115 if (sr_mq_to_cmd_map[i].set_mode) {
116 ret = sr_mq_to_cmd_map[i].set_mode(scpi, mq_flags);
118 ret = sr_scpi_send(scpi, sr_mq_to_cmd_map[i].cmd);
121 devc->measurement_mq = sr_mq_to_cmd_map[i].mq;
122 devc->measurement_mq_flags = mq_flags;
123 devc->measurement_unit = sr_mq_to_cmd_map[i].unit;
131 SR_PRIV const struct rear_card_info *hp_3457a_probe_rear_card(struct sr_scpi_dev_inst *scpi)
135 unsigned int card_id;
136 const struct rear_card_info *rear_card = NULL;
138 if (sr_scpi_get_float(scpi, "OPT?", &card_fval) != SR_OK)
141 card_id = (unsigned int)card_fval;
143 for (i = 0; i < ARRAY_SIZE(rear_card_parameters); i++) {
144 if (rear_card_parameters[i].card_id == card_id) {
145 rear_card = rear_card_parameters + i;
153 sr_info("Found %s.", rear_card->name);
158 SR_PRIV int hp_3457a_set_nplc(const struct sr_dev_inst *sdi, float nplc)
161 struct sr_scpi_dev_inst *scpi = sdi->conn;
162 struct dev_context *devc = sdi->priv;
164 if ((nplc < 1E-6) || (nplc > 100))
167 /* Only need one digit of precision here. */
168 ret = sr_scpi_send(scpi, "NPLC %.0E", nplc);
171 * The instrument only has a few valid NPLC setting, so get back the
172 * one which was selected.
174 sr_scpi_get_float(scpi, "NPLC?", &devc->nplc);
179 /* HIRES register only contains valid data with 10 or more powerline cycles. */
180 static int is_highres_enabled(struct dev_context *devc)
182 return (devc->nplc >= 10.0);
185 static void retrigger_measurement(struct sr_scpi_dev_inst *scpi,
186 struct dev_context *devc)
188 sr_scpi_send(scpi, "?");
189 devc->acq_state = ACQ_TRIGGERED_MEASUREMENT;
192 static void request_hires(struct sr_scpi_dev_inst *scpi,
193 struct dev_context *devc)
195 sr_scpi_send(scpi, "RMATH HIRES");
196 devc->acq_state = ACQ_REQUESTED_HIRES;
199 static void request_range(struct sr_scpi_dev_inst *scpi,
200 struct dev_context *devc)
202 sr_scpi_send(scpi, "RANGE?");
203 devc->acq_state = ACQ_REQUESTED_RANGE;
207 * Calculate the number of leading zeroes in the measurement.
209 * Depending on the range and measurement, a reading may not have eight digits
210 * of resolution. For example, on a 30V range:
211 * : 10.000000 V has 8 significant digits
212 * : 9.999999 V has 7 significant digits
213 * : 0.999999 V has 6 significant digits
215 * The number of significant digits is determined based on the range in which
216 * the measurement was taken:
217 * 1. By taking the base 10 logarithm of the range, and converting that to
218 * an integer, we can get the minimum reading which has a full resolution
219 * reading. Raising 10 to the integer power gives the full resolution.
220 * Ex: For 30 V range, a full resolution reading is 10.000000.
221 * 2. A ratio is taken between the full resolution reading and the
222 * measurement. Since the full resolution reading is a power of 10,
223 * for every leading zero, this ratio will be slightly higher than a
224 * power of 10. For example, for 10 V full resolution:
225 * : 10.000000 V, ratio = 1.0000000
226 * : 9.999999 V, ratio = 1.0000001
227 * : 0.999999 V, ratio = 10.000001
228 * 3. The ratio is rounded up to prevent loss of precision in the next step.
229 * 4. The base 10 logarithm of the ratio is taken, then rounded up. This
230 * gives the number of leading zeroes in the measurement.
231 * For example, for 10 V full resolution:
232 * : 10.000000 V, ceil(1.0000000) = 1, log10 = 0.00; 0 leading zeroes
233 * : 9.999999 V, ceil(1.0000001) = 2, log10 = 0.30; 1 leading zero
234 * : 0.999999 V, ceil(10.000001) = 11, log10 = 1.04, 2 leading zeroes
235 * 5. The number of leading zeroes is subtracted from the maximum number of
236 * significant digits, 8, at 7 1/2 digits resolution.
237 * For a 10 V full resolution reading, this gives:
238 * : 10.000000 V, 0 leading zeroes => 8 significant digits
239 * : 9.999999 V, 1 leading zero => 7 significant digits
240 * : 0.999999 V, 2 leading zeroes => 6 significant digits
242 * Single precision floating point numbers can achieve about 16 million counts,
243 * but in high resolution mode we can get as much as 30 million counts. As a
244 * result, these calculations must be done with double precision
245 * (the HP 3457A is a very precise instrument).
247 static int calculate_num_zero_digits(double measurement, double range)
250 double min_full_res_reading, log10_range, full_res_ratio;
252 log10_range = log10(range);
253 min_full_res_reading = pow(10, (int)log10_range);
254 if (measurement > min_full_res_reading) {
256 } else if (measurement == 0.0) {
259 full_res_ratio = min_full_res_reading / measurement;
260 zero_digits = ceil(log10(ceil(full_res_ratio)));
267 * Until the output modules understand double precision data, we need to send
268 * the measurement as floats instead of doubles, hence, the dance with
269 * measurement_workaround double to float conversion.
270 * See bug #779 for details.
271 * The workaround should be removed once the output modules are fixed.
273 static void acq_send_measurement(struct sr_dev_inst *sdi)
275 double hires_measurement;
276 float measurement_workaround;
277 int zero_digits, num_digits;
278 struct sr_datafeed_packet packet;
279 struct sr_datafeed_analog analog;
280 struct sr_analog_encoding encoding;
281 struct sr_analog_meaning meaning;
282 struct sr_analog_spec spec;
283 struct dev_context *devc = sdi->priv;
285 hires_measurement = devc->base_measurement;
286 if (is_highres_enabled(devc))
287 hires_measurement += devc->hires_register;
289 /* Figure out how many of the digits are significant. */
290 num_digits = is_highres_enabled(devc) ? 8 : 7;
291 zero_digits = calculate_num_zero_digits(hires_measurement,
292 devc->measurement_range);
293 num_digits = num_digits - zero_digits;
295 packet.type = SR_DF_ANALOG;
296 packet.payload = &analog;
298 sr_analog_init(&analog, &encoding, &meaning, &spec, num_digits);
299 encoding.unitsize = sizeof(float);
301 meaning.channels = sdi->channels;
303 measurement_workaround = hires_measurement;
304 analog.num_samples = 1;
305 analog.data = &measurement_workaround;
307 meaning.mq = devc->measurement_mq;
308 meaning.mqflags = devc->measurement_mq_flags;
309 meaning.unit = devc->measurement_unit;
311 sr_session_send(sdi, &packet);
314 SR_PRIV int hp_3457a_receive_data(int fd, int revents, void *cb_data)
317 struct sr_scpi_dev_inst *scpi;
318 struct dev_context *devc;
319 struct sr_dev_inst *sdi = cb_data;
324 if (!(sdi = cb_data))
327 if (!(devc = sdi->priv))
332 switch (devc->acq_state) {
333 case ACQ_TRIGGERED_MEASUREMENT:
334 ret = sr_scpi_get_double(scpi, NULL, &devc->base_measurement);
336 retrigger_measurement(scpi, devc);
340 if (is_highres_enabled(devc))
341 request_hires(scpi, devc);
343 request_range(scpi, devc);
346 case ACQ_REQUESTED_HIRES:
347 ret = sr_scpi_get_double(scpi, NULL, &devc->hires_register);
349 retrigger_measurement(scpi, devc);
352 request_range(scpi, devc);
354 case ACQ_REQUESTED_RANGE:
355 ret = sr_scpi_get_double(scpi, NULL, &devc->measurement_range);
357 retrigger_measurement(scpi, devc);
360 devc->acq_state = ACQ_GOT_MEASUREMENT;
366 if (devc->acq_state == ACQ_GOT_MEASUREMENT) {
367 acq_send_measurement(sdi);
371 if (devc->limit_samples && (devc->num_samples >= devc->limit_samples)) {
372 sdi->driver->dev_acquisition_stop(sdi, cb_data);
376 /* Got more to go. */
377 if (devc->acq_state == ACQ_GOT_MEASUREMENT) {
379 retrigger_measurement(scpi, devc);