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1 | /* | |
2 | * This file is part of the libsigrok project. | |
3 | * | |
4 | * Copyright (C) 2017-2021 Frank Stettner <frank-stettner@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 <config.h> | |
21 | #include <math.h> | |
22 | #include <stdlib.h> | |
23 | #include "scpi.h" | |
24 | #include "protocol.h" | |
25 | ||
26 | static int set_mq_volt(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags); | |
27 | static int set_mq_amp(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags); | |
28 | static int set_mq_ohm(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags); | |
29 | ||
30 | static const struct { | |
31 | enum sr_mq mq; | |
32 | int (*set_mode)(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags); | |
33 | } sr_mq_to_cmd_map[] = { | |
34 | { SR_MQ_VOLTAGE, set_mq_volt }, | |
35 | { SR_MQ_CURRENT, set_mq_amp }, | |
36 | { SR_MQ_RESISTANCE, set_mq_ohm }, | |
37 | }; | |
38 | ||
39 | static int set_mq_volt(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags) | |
40 | { | |
41 | if ((flags & SR_MQFLAG_AC) != SR_MQFLAG_AC && | |
42 | (flags & SR_MQFLAG_DC) != SR_MQFLAG_DC) | |
43 | return SR_ERR_NA; | |
44 | ||
45 | return sr_scpi_send(scpi, "%s", | |
46 | ((flags & SR_MQFLAG_AC) == SR_MQFLAG_AC) ? "F2" : "F1"); | |
47 | } | |
48 | ||
49 | static int set_mq_amp(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags) | |
50 | { | |
51 | if ((flags & SR_MQFLAG_AC) != SR_MQFLAG_AC && | |
52 | (flags & SR_MQFLAG_DC) != SR_MQFLAG_DC) | |
53 | return SR_ERR_NA; | |
54 | ||
55 | return sr_scpi_send(scpi, "%s", (flags & SR_MQFLAG_AC) ? "F6" : "F5"); | |
56 | } | |
57 | ||
58 | static int set_mq_ohm(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags) | |
59 | { | |
60 | return sr_scpi_send(scpi, "%s", | |
61 | (flags & SR_MQFLAG_FOUR_WIRE) ? "F4" : "F3"); | |
62 | } | |
63 | ||
64 | SR_PRIV int hp_3478a_set_mq(const struct sr_dev_inst *sdi, enum sr_mq mq, | |
65 | enum sr_mqflag mq_flags) | |
66 | { | |
67 | int ret; | |
68 | size_t i; | |
69 | struct sr_scpi_dev_inst *scpi = sdi->conn; | |
70 | struct dev_context *devc = sdi->priv; | |
71 | ||
72 | /* No need to send a command if we're not changing the measurement type. */ | |
73 | if (devc->measurement_mq == mq && devc->measurement_mq_flag == mq_flags) | |
74 | return SR_OK; | |
75 | ||
76 | for (i = 0; i < ARRAY_SIZE(sr_mq_to_cmd_map); i++) { | |
77 | if (sr_mq_to_cmd_map[i].mq != mq) | |
78 | continue; | |
79 | ||
80 | ret = sr_mq_to_cmd_map[i].set_mode(scpi, mq_flags); | |
81 | if (ret != SR_OK) | |
82 | return ret; | |
83 | ||
84 | ret = hp_3478a_get_status_bytes(sdi); | |
85 | return ret; | |
86 | } | |
87 | ||
88 | return SR_ERR_NA; | |
89 | } | |
90 | ||
91 | SR_PRIV int hp_3478a_set_range(const struct sr_dev_inst *sdi, int range_exp) | |
92 | { | |
93 | int ret; | |
94 | struct sr_scpi_dev_inst *scpi = sdi->conn; | |
95 | struct dev_context *devc = sdi->priv; | |
96 | ||
97 | /* No need to send command if we're not changing the range. */ | |
98 | if (devc->range_exp == range_exp) | |
99 | return SR_OK; | |
100 | ||
101 | /* -99 is a dummy exponent for auto ranging. */ | |
102 | if (range_exp == -99) | |
103 | ret = sr_scpi_send(scpi, "RA"); | |
104 | else | |
105 | ret = sr_scpi_send(scpi, "R%i", range_exp); | |
106 | if (ret != SR_OK) | |
107 | return ret; | |
108 | ||
109 | return hp_3478a_get_status_bytes(sdi); | |
110 | } | |
111 | ||
112 | SR_PRIV int hp_3478a_set_digits(const struct sr_dev_inst *sdi, uint8_t digits) | |
113 | { | |
114 | int ret; | |
115 | struct sr_scpi_dev_inst *scpi = sdi->conn; | |
116 | struct dev_context *devc = sdi->priv; | |
117 | ||
118 | /* No need to send command if we're not changing the resolution. */ | |
119 | if (devc->digits == digits) | |
120 | return SR_OK; | |
121 | ||
122 | /* digits are the total number of digits, so we have to substract 1 */ | |
123 | ret = sr_scpi_send(scpi, "N%i", digits-1); | |
124 | if (ret != SR_OK) | |
125 | return ret; | |
126 | ||
127 | return hp_3478a_get_status_bytes(sdi); | |
128 | } | |
129 | ||
130 | static int parse_range_vdc(struct dev_context *devc, uint8_t range_byte) | |
131 | { | |
132 | if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_30MV) { | |
133 | devc->range_exp = -2; | |
134 | devc->sr_digits = devc->digits + 1; | |
135 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_300MV) { | |
136 | devc->range_exp = -1; | |
137 | devc->sr_digits = devc->digits; | |
138 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_3V) { | |
139 | devc->range_exp = 0; | |
140 | devc->sr_digits = devc->digits - 1; | |
141 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_30V) { | |
142 | devc->range_exp = 1; | |
143 | devc->sr_digits = devc->digits - 2; | |
144 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_300V) { | |
145 | devc->range_exp = 2; | |
146 | devc->sr_digits = devc->digits - 3; | |
147 | } else | |
148 | return SR_ERR_DATA; | |
149 | ||
150 | return SR_OK; | |
151 | } | |
152 | ||
153 | static int parse_range_vac(struct dev_context *devc, uint8_t range_byte) | |
154 | { | |
155 | if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_300MV) { | |
156 | devc->range_exp = -1; | |
157 | devc->sr_digits = devc->digits; | |
158 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_3V) { | |
159 | devc->range_exp = 0; | |
160 | devc->sr_digits = devc->digits - 1; | |
161 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_30V) { | |
162 | devc->range_exp = 1; | |
163 | devc->sr_digits = devc->digits - 2; | |
164 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_300V) { | |
165 | devc->range_exp = 2; | |
166 | devc->sr_digits = devc->digits - 3; | |
167 | } else | |
168 | return SR_ERR_DATA; | |
169 | ||
170 | return SR_OK; | |
171 | } | |
172 | ||
173 | static int parse_range_a(struct dev_context *devc, uint8_t range_byte) | |
174 | { | |
175 | if ((range_byte & SB1_RANGE_BLOCK) == RANGE_A_300MA) { | |
176 | devc->range_exp = -1; | |
177 | devc->sr_digits = devc->digits; | |
178 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_A_3A) { | |
179 | devc->range_exp = 0; | |
180 | devc->sr_digits = devc->digits - 1; | |
181 | } else | |
182 | return SR_ERR_DATA; | |
183 | ||
184 | return SR_OK; | |
185 | } | |
186 | ||
187 | static int parse_range_ohm(struct dev_context *devc, uint8_t range_byte) | |
188 | { | |
189 | if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_30R) { | |
190 | devc->range_exp = 1; | |
191 | devc->sr_digits = devc->digits - 2; | |
192 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_300R) { | |
193 | devc->range_exp = 2; | |
194 | devc->sr_digits = devc->digits - 3; | |
195 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_3KR) { | |
196 | devc->range_exp = 3; | |
197 | devc->sr_digits = devc->digits - 4; | |
198 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_30KR) { | |
199 | devc->range_exp = 4; | |
200 | devc->sr_digits = devc->digits - 5; | |
201 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_300KR) { | |
202 | devc->range_exp = 5; | |
203 | devc->sr_digits = devc->digits - 6; | |
204 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_3MR) { | |
205 | devc->range_exp = 6; | |
206 | devc->sr_digits = devc->digits - 7; | |
207 | } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_30MR) { | |
208 | devc->range_exp = 7; | |
209 | devc->sr_digits = devc->digits - 8; | |
210 | } else | |
211 | return SR_ERR_DATA; | |
212 | ||
213 | return SR_OK; | |
214 | } | |
215 | ||
216 | static int parse_function_byte(struct dev_context *devc, uint8_t function_byte) | |
217 | { | |
218 | /* Digits / Resolution (digits must be set before range parsing) */ | |
219 | if ((function_byte & SB1_DIGITS_BLOCK) == DIGITS_5_5) | |
220 | devc->digits = 6; | |
221 | else if ((function_byte & SB1_DIGITS_BLOCK) == DIGITS_4_5) | |
222 | devc->digits = 5; | |
223 | else if ((function_byte & SB1_DIGITS_BLOCK) == DIGITS_3_5) | |
224 | devc->digits = 4; | |
225 | else | |
226 | return SR_ERR_DATA; | |
227 | ||
228 | /* Function + Range */ | |
229 | devc->measurement_mq_flag = 0; | |
230 | devc->acquisition_mq_flags = 0; | |
231 | if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_VDC) { | |
232 | devc->measurement_mq = SR_MQ_VOLTAGE; | |
233 | devc->measurement_mq_flag = SR_MQFLAG_DC; | |
234 | devc->acquisition_mq_flags |= SR_MQFLAG_DC; | |
235 | devc->measurement_unit = SR_UNIT_VOLT; | |
236 | parse_range_vdc(devc, function_byte); | |
237 | } else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_VAC) { | |
238 | devc->measurement_mq = SR_MQ_VOLTAGE; | |
239 | devc->measurement_mq_flag = SR_MQFLAG_AC; | |
240 | devc->acquisition_mq_flags |= SR_MQFLAG_AC | SR_MQFLAG_RMS; | |
241 | devc->measurement_unit = SR_UNIT_VOLT; | |
242 | parse_range_vac(devc, function_byte); | |
243 | } else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_2WR) { | |
244 | devc->measurement_mq = SR_MQ_RESISTANCE; | |
245 | devc->measurement_unit = SR_UNIT_OHM; | |
246 | parse_range_ohm(devc, function_byte); | |
247 | } else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_4WR) { | |
248 | devc->measurement_mq = SR_MQ_RESISTANCE; | |
249 | devc->measurement_mq_flag = SR_MQFLAG_FOUR_WIRE; | |
250 | devc->acquisition_mq_flags |= SR_MQFLAG_FOUR_WIRE; | |
251 | devc->measurement_unit = SR_UNIT_OHM; | |
252 | parse_range_ohm(devc, function_byte); | |
253 | } else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_ADC) { | |
254 | devc->measurement_mq = SR_MQ_CURRENT; | |
255 | devc->measurement_mq_flag = SR_MQFLAG_DC; | |
256 | devc->acquisition_mq_flags |= SR_MQFLAG_DC; | |
257 | devc->measurement_unit = SR_UNIT_AMPERE; | |
258 | parse_range_a(devc, function_byte); | |
259 | } else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_AAC) { | |
260 | devc->measurement_mq = SR_MQ_CURRENT; | |
261 | devc->measurement_mq_flag = SR_MQFLAG_AC; | |
262 | devc->acquisition_mq_flags |= SR_MQFLAG_AC | SR_MQFLAG_RMS; | |
263 | devc->measurement_unit = SR_UNIT_AMPERE; | |
264 | parse_range_a(devc, function_byte); | |
265 | } else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_EXR) { | |
266 | devc->measurement_mq = SR_MQ_RESISTANCE; | |
267 | devc->measurement_unit = SR_UNIT_OHM; | |
268 | parse_range_ohm(devc, function_byte); | |
269 | } | |
270 | ||
271 | return SR_OK; | |
272 | } | |
273 | ||
274 | static int parse_status_byte(struct dev_context *devc, uint8_t status_byte) | |
275 | { | |
276 | devc->trigger = TRIGGER_UNDEFINED; | |
277 | ||
278 | /* External Trigger */ | |
279 | if ((status_byte & STATUS_EXT_TRIGGER) == STATUS_EXT_TRIGGER) | |
280 | devc->trigger = TRIGGER_EXTERNAL; | |
281 | ||
282 | /* Cal RAM */ | |
283 | if ((status_byte & STATUS_CAL_RAM) == STATUS_CAL_RAM) | |
284 | devc->calibration = TRUE; | |
285 | else | |
286 | devc->calibration = FALSE; | |
287 | ||
288 | /* Front/Rear terminals */ | |
289 | if ((status_byte & STATUS_FRONT_TERMINAL) == STATUS_FRONT_TERMINAL) | |
290 | devc->terminal = TERMINAL_FRONT; | |
291 | else | |
292 | devc->terminal = TERMINAL_REAR; | |
293 | ||
294 | /* 50Hz / 60Hz */ | |
295 | if ((status_byte & STATUS_50HZ) == STATUS_50HZ) | |
296 | devc->line = LINE_50HZ; | |
297 | else | |
298 | devc->line = LINE_60HZ; | |
299 | ||
300 | /* Auto-Zero */ | |
301 | if ((status_byte & STATUS_AUTO_ZERO) == STATUS_AUTO_ZERO) | |
302 | devc->auto_zero = TRUE; | |
303 | else | |
304 | devc->auto_zero = FALSE; | |
305 | ||
306 | /* Auto-Range */ | |
307 | if ((status_byte & STATUS_AUTO_RANGE) == STATUS_AUTO_RANGE) { | |
308 | devc->acquisition_mq_flags |= SR_MQFLAG_AUTORANGE; | |
309 | devc->range_exp = -99; | |
310 | } else | |
311 | devc->acquisition_mq_flags &= ~SR_MQFLAG_AUTORANGE; | |
312 | ||
313 | /* Internal trigger */ | |
314 | if ((status_byte & STATUS_INT_TRIGGER) == STATUS_INT_TRIGGER) | |
315 | devc->trigger = TRIGGER_INTERNAL; | |
316 | ||
317 | return SR_OK; | |
318 | } | |
319 | ||
320 | static int parse_srq_byte(uint8_t sqr_byte) | |
321 | { | |
322 | (void)sqr_byte; | |
323 | ||
324 | #if 0 | |
325 | /* The ServiceReQuest register isn't used at the moment. */ | |
326 | ||
327 | /* PON SRQ */ | |
328 | if ((sqr_byte & SRQ_POWER_ON) == SRQ_POWER_ON) | |
329 | sr_spew("Power On SRQ or clear msg received"); | |
330 | ||
331 | /* Cal failed SRQ */ | |
332 | if ((sqr_byte & SRQ_CAL_FAILED) == SRQ_CAL_FAILED) | |
333 | sr_spew("CAL failed SRQ"); | |
334 | ||
335 | /* Keyboard SRQ */ | |
336 | if ((sqr_byte & SRQ_KEYBORD) == SRQ_KEYBORD) | |
337 | sr_spew("Keyboard SRQ"); | |
338 | ||
339 | /* Hardware error SRQ */ | |
340 | if ((sqr_byte & SRQ_HARDWARE_ERR) == SRQ_HARDWARE_ERR) | |
341 | sr_spew("Hardware error SRQ"); | |
342 | ||
343 | /* Syntax error SRQ */ | |
344 | if ((sqr_byte & SRQ_SYNTAX_ERR) == SRQ_SYNTAX_ERR) | |
345 | sr_spew("Syntax error SRQ"); | |
346 | ||
347 | /* Every reading is available to the bus SRQ */ | |
348 | if ((sqr_byte & SRQ_BUS_AVAIL) == SRQ_BUS_AVAIL) | |
349 | sr_spew("Every reading is available to the bus SRQ"); | |
350 | #endif | |
351 | ||
352 | return SR_OK; | |
353 | } | |
354 | ||
355 | static int parse_error_byte(uint8_t error_byte) | |
356 | { | |
357 | int ret; | |
358 | ||
359 | ret = SR_OK; | |
360 | ||
361 | /* A/D link */ | |
362 | if ((error_byte & ERROR_AD_LINK) == ERROR_AD_LINK) { | |
363 | sr_err("Failure in the A/D link"); | |
364 | ret = SR_ERR; | |
365 | } | |
366 | ||
367 | /* A/D Self Test */ | |
368 | if ((error_byte & ERROR_AD_SELF_TEST) == ERROR_AD_SELF_TEST) { | |
369 | sr_err("A/D has failed its internal Self Test"); | |
370 | ret = SR_ERR; | |
371 | } | |
372 | ||
373 | /* A/D slope error */ | |
374 | if ((error_byte & ERROR_AD_SLOPE) == ERROR_AD_SLOPE) { | |
375 | sr_err("There has been an A/D slope error"); | |
376 | ret = SR_ERR; | |
377 | } | |
378 | ||
379 | /* ROM Selt Test */ | |
380 | if ((error_byte & ERROR_ROM_SELF_TEST) == ERROR_ROM_SELF_TEST) { | |
381 | sr_err("The ROM Self Test has failed"); | |
382 | ret = SR_ERR; | |
383 | } | |
384 | ||
385 | /* RAM Selt Test */ | |
386 | if ((error_byte & ERROR_RAM_SELF_TEST) == ERROR_RAM_SELF_TEST) { | |
387 | sr_err("The RAM Self Test has failed"); | |
388 | ret = SR_ERR; | |
389 | } | |
390 | ||
391 | /* Selt Test */ | |
392 | if ((error_byte & ERROR_SELF_TEST) == ERROR_SELF_TEST) { | |
393 | sr_err("Self Test: Any of the CAL RAM locations have bad " | |
394 | "checksums, or a range with a bad checksum is selected"); | |
395 | ret = SR_ERR; | |
396 | } | |
397 | ||
398 | return ret; | |
399 | } | |
400 | ||
401 | SR_PRIV int hp_3478a_get_status_bytes(const struct sr_dev_inst *sdi) | |
402 | { | |
403 | int ret; | |
404 | char *response; | |
405 | uint8_t function_byte, status_byte, srq_byte, error_byte; | |
406 | struct sr_scpi_dev_inst *scpi = sdi->conn; | |
407 | struct dev_context *devc = sdi->priv; | |
408 | ||
409 | ret = sr_scpi_get_string(scpi, "B", &response); | |
410 | if (ret != SR_OK) | |
411 | return ret; | |
412 | ||
413 | if (!response) | |
414 | return SR_ERR; | |
415 | ||
416 | function_byte = (uint8_t)response[0]; | |
417 | status_byte = (uint8_t)response[1]; | |
418 | srq_byte = (uint8_t)response[2]; | |
419 | error_byte = (uint8_t)response[3]; | |
420 | ||
421 | g_free(response); | |
422 | ||
423 | parse_function_byte(devc, function_byte); | |
424 | parse_status_byte(devc, status_byte); | |
425 | parse_srq_byte(srq_byte); | |
426 | ret = parse_error_byte(error_byte); | |
427 | ||
428 | return ret; | |
429 | } | |
430 | ||
431 | static void acq_send_measurement(struct sr_dev_inst *sdi) | |
432 | { | |
433 | struct sr_datafeed_packet packet; | |
434 | struct sr_datafeed_analog analog; | |
435 | struct sr_analog_encoding encoding; | |
436 | struct sr_analog_meaning meaning; | |
437 | struct sr_analog_spec spec; | |
438 | struct dev_context *devc; | |
439 | float f; | |
440 | ||
441 | devc = sdi->priv; | |
442 | ||
443 | packet.type = SR_DF_ANALOG; | |
444 | packet.payload = &analog; | |
445 | ||
446 | sr_analog_init(&analog, &encoding, &meaning, &spec, devc->sr_digits); | |
447 | ||
448 | /* TODO: Implement NAN, depending on counts, range and value. */ | |
449 | f = devc->measurement; | |
450 | analog.num_samples = 1; | |
451 | analog.data = &f; | |
452 | ||
453 | encoding.unitsize = sizeof(float); | |
454 | encoding.is_float = TRUE; | |
455 | encoding.digits = devc->sr_digits; | |
456 | ||
457 | meaning.mq = devc->measurement_mq; | |
458 | meaning.mqflags = devc->acquisition_mq_flags; | |
459 | meaning.unit = devc->measurement_unit; | |
460 | meaning.channels = sdi->channels; | |
461 | ||
462 | spec.spec_digits = devc->sr_digits; | |
463 | ||
464 | sr_session_send(sdi, &packet); | |
465 | } | |
466 | ||
467 | SR_PRIV int hp_3478a_receive_data(int fd, int revents, void *cb_data) | |
468 | { | |
469 | struct sr_scpi_dev_inst *scpi; | |
470 | struct sr_dev_inst *sdi; | |
471 | struct dev_context *devc; | |
472 | char status_register; | |
473 | ||
474 | (void)fd; | |
475 | (void)revents; | |
476 | ||
477 | if (!(sdi = cb_data) || !(devc = sdi->priv)) | |
478 | return TRUE; | |
479 | ||
480 | scpi = sdi->conn; | |
481 | ||
482 | /* | |
483 | * TODO: Wait for SRQ from the DMM when a new measurement is available. | |
484 | * For now, we don't wait for a SRQ, but just do a SPoll and | |
485 | * check the Data Ready bit (0x01). | |
486 | * This is necessary, because (1) reading a value will block the | |
487 | * bus until a measurement is available and (2) when switching | |
488 | * ranges, there could be a timeout. | |
489 | */ | |
490 | if (sr_scpi_gpib_spoll(scpi, &status_register) != SR_OK) | |
491 | return FALSE; | |
492 | if (!(((uint8_t)status_register) & SRQ_BUS_AVAIL)) | |
493 | return TRUE; | |
494 | ||
495 | /* Get a reading from the DMM. */ | |
496 | if (sr_scpi_get_double(scpi, NULL, &devc->measurement) != SR_OK) | |
497 | return FALSE; | |
498 | ||
499 | /* Check for overflow. */ | |
500 | if (devc->measurement >= 9.998e+9) | |
501 | devc->measurement = INFINITY; | |
502 | ||
503 | /* | |
504 | * This is necessary to get the actual range for the encoding digits. | |
505 | * Must be called after reading the value, because it resets the | |
506 | * status register! | |
507 | */ | |
508 | if (hp_3478a_get_status_bytes(sdi) != SR_OK) | |
509 | return FALSE; | |
510 | ||
511 | acq_send_measurement(sdi); | |
512 | sr_sw_limits_update_samples_read(&devc->limits, 1); | |
513 | ||
514 | if (sr_sw_limits_check(&devc->limits)) | |
515 | sr_dev_acquisition_stop(sdi); | |
516 | ||
517 | return TRUE; | |
518 | } |