libsigrok/src/hardware/hp-3478a/protocol.c

520 lines
15 KiB
C

/*
* This file is part of the libsigrok project.
*
* Copyright (C) 2017-2018 Frank Stettner <frank-stettner@gmx.net>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include <math.h>
#include <stdlib.h>
#include "scpi.h"
#include "protocol.h"
static int set_mq_volt(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags);
static int set_mq_amp(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags);
static int set_mq_ohm(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags);
static const struct {
enum sr_mq mq;
int (*set_mode)(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags);
} sr_mq_to_cmd_map[] = {
{ SR_MQ_VOLTAGE, set_mq_volt },
{ SR_MQ_CURRENT, set_mq_amp },
{ SR_MQ_RESISTANCE, set_mq_ohm },
};
static int set_mq_volt(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags)
{
if ((flags & SR_MQFLAG_AC) != SR_MQFLAG_AC &&
(flags & SR_MQFLAG_DC) != SR_MQFLAG_DC)
return SR_ERR_NA;
return sr_scpi_send(scpi, "%s",
((flags & SR_MQFLAG_AC) == SR_MQFLAG_AC) ? "F2" : "F1");
}
static int set_mq_amp(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags)
{
if ((flags & SR_MQFLAG_AC) != SR_MQFLAG_AC &&
(flags & SR_MQFLAG_DC) != SR_MQFLAG_DC)
return SR_ERR_NA;
return sr_scpi_send(scpi, "%s", (flags & SR_MQFLAG_AC) ? "F6" : "F5");
}
static int set_mq_ohm(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags)
{
return sr_scpi_send(scpi, "%s",
(flags & SR_MQFLAG_FOUR_WIRE) ? "F4" : "F3");
}
SR_PRIV int hp_3478a_set_mq(const struct sr_dev_inst *sdi, enum sr_mq mq,
enum sr_mqflag mq_flags)
{
int ret;
size_t i;
struct sr_scpi_dev_inst *scpi = sdi->conn;
struct dev_context *devc = sdi->priv;
/* No need to send command if we're not changing measurement type. */
if (devc->measurement_mq == mq &&
((devc->measurement_mq_flags & mq_flags) == mq_flags))
return SR_OK;
for (i = 0; i < ARRAY_SIZE(sr_mq_to_cmd_map); i++) {
if (sr_mq_to_cmd_map[i].mq != mq)
continue;
ret = sr_mq_to_cmd_map[i].set_mode(scpi, mq_flags);
if (ret != SR_OK)
return ret;
ret = hp_3478a_get_status_bytes(sdi);
return ret;
}
return SR_ERR_NA;
}
SR_PRIV int hp_3478a_set_range(const struct sr_dev_inst *sdi, int range_exp)
{
int ret;
struct sr_scpi_dev_inst *scpi = sdi->conn;
struct dev_context *devc = sdi->priv;
/* No need to send command if we're not changing the range. */
if (devc->range_exp == range_exp)
return SR_OK;
/* -99 is a dummy exponent for auto ranging. */
if (range_exp == -99)
ret = sr_scpi_send(scpi, "RA");
else
ret = sr_scpi_send(scpi, "R%i", range_exp);
if (ret != SR_OK)
return ret;
return hp_3478a_get_status_bytes(sdi);
}
SR_PRIV int hp_3478a_set_digits(const struct sr_dev_inst *sdi, uint8_t digits)
{
int ret;
struct sr_scpi_dev_inst *scpi = sdi->conn;
struct dev_context *devc = sdi->priv;
/* No need to send command if we're not changing the range. */
if (devc->spec_digits == digits)
return SR_OK;
/* digits are based on devc->spec_digits, so we have to substract 1 */
ret = sr_scpi_send(scpi, "N%i", digits-1);
if (ret != SR_OK)
return ret;
return hp_3478a_get_status_bytes(sdi);
}
static int parse_range_vdc(struct dev_context *devc, uint8_t range_byte)
{
if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_30MV) {
devc->range_exp = -2;
devc->enc_digits = devc->spec_digits - 2;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_300MV) {
devc->range_exp = -1;
devc->enc_digits = devc->spec_digits - 3;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_3V) {
devc->range_exp = 0;
devc->enc_digits = devc->spec_digits - 1;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_30V) {
devc->range_exp = 1;
devc->enc_digits = devc->spec_digits - 2;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_300V) {
devc->range_exp = 2;
devc->enc_digits = devc->spec_digits - 3;
} else
return SR_ERR_DATA;
return SR_OK;
}
static int parse_range_vac(struct dev_context *devc, uint8_t range_byte)
{
if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_300MV) {
devc->range_exp = -1;
devc->enc_digits = devc->spec_digits - 3;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_3V) {
devc->range_exp = 0;
devc->enc_digits = devc->spec_digits - 1;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_30V) {
devc->range_exp = 1;
devc->enc_digits = devc->spec_digits - 2;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_300V) {
devc->range_exp = 2;
devc->enc_digits = devc->spec_digits - 3;
} else
return SR_ERR_DATA;
return SR_OK;
}
static int parse_range_a(struct dev_context *devc, uint8_t range_byte)
{
if ((range_byte & SB1_RANGE_BLOCK) == RANGE_A_300MA) {
devc->range_exp = -1;
devc->enc_digits = devc->spec_digits - 3;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_A_3A) {
devc->range_exp = 0;
devc->enc_digits = devc->spec_digits - 1;
} else
return SR_ERR_DATA;
return SR_OK;
}
static int parse_range_ohm(struct dev_context *devc, uint8_t range_byte)
{
if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_30R) {
devc->range_exp = 1;
devc->enc_digits = devc->spec_digits - 2;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_300R) {
devc->range_exp = 2;
devc->enc_digits = devc->spec_digits - 3;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_3KR) {
devc->range_exp = 3;
devc->enc_digits = devc->spec_digits - 1;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_30KR) {
devc->range_exp = 4;
devc->enc_digits = devc->spec_digits - 2;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_300KR) {
devc->range_exp = 5;
devc->enc_digits = devc->spec_digits - 3;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_3MR) {
devc->range_exp = 6;
devc->enc_digits = devc->spec_digits - 1;
} else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_30MR) {
devc->range_exp = 7;
devc->enc_digits = devc->spec_digits - 2;
} else
return SR_ERR_DATA;
return SR_OK;
}
static int parse_function_byte(struct dev_context *devc, uint8_t function_byte)
{
/* Digits / Resolution (spec_digits must be set before range parsing) */
if ((function_byte & SB1_DIGITS_BLOCK) == DIGITS_5_5)
devc->spec_digits = 6;
else if ((function_byte & SB1_DIGITS_BLOCK) == DIGITS_4_5)
devc->spec_digits = 5;
else if ((function_byte & SB1_DIGITS_BLOCK) == DIGITS_3_5)
devc->spec_digits = 4;
else
return SR_ERR_DATA;
/* Function + Range */
devc->measurement_mq_flags = 0;
devc->acquisition_mq_flags = 0;
if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_VDC) {
devc->measurement_mq = SR_MQ_VOLTAGE;
devc->measurement_mq_flags |= SR_MQFLAG_DC;
devc->acquisition_mq_flags |= SR_MQFLAG_DC;
devc->measurement_unit = SR_UNIT_VOLT;
parse_range_vdc(devc, function_byte);
} else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_VAC) {
devc->measurement_mq = SR_MQ_VOLTAGE;
devc->measurement_mq_flags |= SR_MQFLAG_AC;
devc->acquisition_mq_flags |= SR_MQFLAG_AC | SR_MQFLAG_RMS;
devc->measurement_unit = SR_UNIT_VOLT;
parse_range_vac(devc, function_byte);
} else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_2WR) {
devc->measurement_mq = SR_MQ_RESISTANCE;
devc->measurement_unit = SR_UNIT_OHM;
parse_range_ohm(devc, function_byte);
} else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_4WR) {
devc->measurement_mq = SR_MQ_RESISTANCE;
devc->measurement_mq_flags |= SR_MQFLAG_FOUR_WIRE;
devc->acquisition_mq_flags |= SR_MQFLAG_FOUR_WIRE;
devc->measurement_unit = SR_UNIT_OHM;
parse_range_ohm(devc, function_byte);
} else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_ADC) {
devc->measurement_mq = SR_MQ_CURRENT;
devc->measurement_mq_flags |= SR_MQFLAG_DC;
devc->acquisition_mq_flags |= SR_MQFLAG_DC;
devc->measurement_unit = SR_UNIT_AMPERE;
parse_range_a(devc, function_byte);
} else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_AAC) {
devc->measurement_mq = SR_MQ_CURRENT;
devc->measurement_mq_flags |= SR_MQFLAG_AC;
devc->acquisition_mq_flags |= SR_MQFLAG_AC | SR_MQFLAG_RMS;
devc->measurement_unit = SR_UNIT_AMPERE;
parse_range_a(devc, function_byte);
} else if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_EXR) {
devc->measurement_mq = SR_MQ_RESISTANCE;
devc->measurement_unit = SR_UNIT_OHM;
parse_range_ohm(devc, function_byte);
}
return SR_OK;
}
static int parse_status_byte(struct dev_context *devc, uint8_t status_byte)
{
devc->trigger = TRIGGER_UNDEFINED;
/* External Trigger */
if ((status_byte & STATUS_EXT_TRIGGER) == STATUS_EXT_TRIGGER)
devc->trigger = TRIGGER_EXTERNAL;
/* Cal RAM */
if ((status_byte & STATUS_CAL_RAM) == STATUS_CAL_RAM)
devc->calibration = TRUE;
else
devc->calibration = FALSE;
/* Front/Rear terminals */
if ((status_byte & STATUS_FRONT_TERMINAL) == STATUS_FRONT_TERMINAL)
devc->terminal = TERMINAL_FRONT;
else
devc->terminal = TERMINAL_REAR;
/* 50Hz / 60Hz */
if ((status_byte & STATUS_50HZ) == STATUS_50HZ)
devc->line = LINE_50HZ;
else
devc->line = LINE_60HZ;
/* Auto-Zero */
if ((status_byte & STATUS_AUTO_ZERO) == STATUS_AUTO_ZERO)
devc->auto_zero = TRUE;
else
devc->auto_zero = FALSE;
/* Auto-Range */
if ((status_byte & STATUS_AUTO_RANGE) == STATUS_AUTO_RANGE) {
devc->acquisition_mq_flags |= SR_MQFLAG_AUTORANGE;
devc->range_exp = -99;
} else
devc->acquisition_mq_flags &= ~SR_MQFLAG_AUTORANGE;
/* Internal trigger */
if ((status_byte & STATUS_INT_TRIGGER) == STATUS_INT_TRIGGER)
devc->trigger = TRIGGER_INTERNAL;
return SR_OK;
}
static int parse_srq_byte(uint8_t sqr_byte)
{
(void)sqr_byte;
#if 0
/* The ServiceReQuest register isn't used at the moment. */
/* PON SRQ */
if ((sqr_byte & SRQ_POWER_ON) == SRQ_POWER_ON)
sr_spew("Power On SRQ or clear msg received");
/* Cal failed SRQ */
if ((sqr_byte & SRQ_CAL_FAILED) == SRQ_CAL_FAILED)
sr_spew("CAL failed SRQ");
/* Keyboard SRQ */
if ((sqr_byte & SRQ_KEYBORD) == SRQ_KEYBORD)
sr_spew("Keyboard SRQ");
/* Hardware error SRQ */
if ((sqr_byte & SRQ_HARDWARE_ERR) == SRQ_HARDWARE_ERR)
sr_spew("Hardware error SRQ");
/* Syntax error SRQ */
if ((sqr_byte & SRQ_SYNTAX_ERR) == SRQ_SYNTAX_ERR)
sr_spew("Syntax error SRQ");
/* Every reading is available to the bus SRQ */
if ((sqr_byte & SRQ_BUS_AVAIL) == SRQ_BUS_AVAIL)
sr_spew("Every reading is available to the bus SRQ");
#endif
return SR_OK;
}
static int parse_error_byte(uint8_t error_byte)
{
int ret;
ret = SR_OK;
/* A/D link */
if ((error_byte & ERROR_AD_LINK) == ERROR_AD_LINK) {
sr_err("Failure in the A/D link");
ret = SR_ERR;
}
/* A/D Self Test */
if ((error_byte & ERROR_AD_SELF_TEST) == ERROR_AD_SELF_TEST) {
sr_err("A/D has failed its internal Self Test");
ret = SR_ERR;
}
/* A/D slope error */
if ((error_byte & ERROR_AD_SLOPE) == ERROR_AD_SLOPE) {
sr_err("There has been an A/D slope error");
ret = SR_ERR;
}
/* ROM Selt Test */
if ((error_byte & ERROR_ROM_SELF_TEST) == ERROR_ROM_SELF_TEST) {
sr_err("The ROM Self Test has failed");
ret = SR_ERR;
}
/* RAM Selt Test */
if ((error_byte & ERROR_RAM_SELF_TEST) == ERROR_RAM_SELF_TEST) {
sr_err("The RAM Self Test has failed");
ret = SR_ERR;
}
/* Selt Test */
if ((error_byte & ERROR_SELF_TEST) == ERROR_SELF_TEST) {
sr_err("Self Test: Any of the CAL RAM locations have bad "
"checksums, or a range with a bad checksum is selected");
ret = SR_ERR;
}
return ret;
}
SR_PRIV int hp_3478a_get_status_bytes(const struct sr_dev_inst *sdi)
{
int ret;
char *response;
uint8_t function_byte, status_byte, srq_byte, error_byte;
struct sr_scpi_dev_inst *scpi = sdi->conn;
struct dev_context *devc = sdi->priv;
ret = sr_scpi_get_string(scpi, "B", &response);
if (ret != SR_OK)
return ret;
if (!response)
return SR_ERR;
function_byte = (uint8_t)response[0];
status_byte = (uint8_t)response[1];
srq_byte = (uint8_t)response[2];
error_byte = (uint8_t)response[3];
g_free(response);
parse_function_byte(devc, function_byte);
parse_status_byte(devc, status_byte);
parse_srq_byte(srq_byte);
ret = parse_error_byte(error_byte);
return ret;
}
static void acq_send_measurement(struct sr_dev_inst *sdi)
{
struct sr_datafeed_packet packet;
struct sr_datafeed_analog analog;
struct sr_analog_encoding encoding;
struct sr_analog_meaning meaning;
struct sr_analog_spec spec;
struct dev_context *devc;
float f;
devc = sdi->priv;
packet.type = SR_DF_ANALOG;
packet.payload = &analog;
sr_analog_init(&analog, &encoding, &meaning, &spec, devc->enc_digits);
/* TODO: Implement NAN, depending on counts, range and value. */
f = devc->measurement;
analog.num_samples = 1;
analog.data = &f;
encoding.unitsize = sizeof(float);
encoding.is_float = TRUE;
encoding.digits = devc->enc_digits;
meaning.mq = devc->measurement_mq;
meaning.mqflags = devc->acquisition_mq_flags;
meaning.unit = devc->measurement_unit;
meaning.channels = sdi->channels;
spec.spec_digits = devc->spec_digits;
sr_session_send(sdi, &packet);
}
SR_PRIV int hp_3478a_receive_data(int fd, int revents, void *cb_data)
{
struct sr_scpi_dev_inst *scpi;
struct sr_dev_inst *sdi;
struct dev_context *devc;
char status_register;
(void)fd;
(void)revents;
if (!(sdi = cb_data) || !(devc = sdi->priv))
return TRUE;
scpi = sdi->conn;
/*
* TODO: Wait for SRQ from the DMM when a new measurement is available.
* For now, we don't wait for a SRQ, but just do a SPoll and
* check the Data Ready bit (0x01).
* This is necessary, because (1) reading a value will block the
* bus until a measurement is available and (2) when switching
* ranges, there could be a timeout.
*/
if (sr_scpi_gpib_spoll(scpi, &status_register) != SR_OK)
return FALSE;
if (!(((uint8_t)status_register) & 0x01))
return TRUE;
/* Get a reading from the DMM. */
if (sr_scpi_get_double(scpi, NULL, &devc->measurement) != SR_OK)
return FALSE;
/* Check for overflow. */
if (devc->measurement >= 9.998e+9)
devc->measurement = INFINITY;
/*
* This is necessary to get the actual range for the encoding digits.
* Must be called after reading the value, because it resets the
* status register!
*/
if (hp_3478a_get_status_bytes(sdi) != SR_OK)
return FALSE;
acq_send_measurement(sdi);
sr_sw_limits_update_samples_read(&devc->limits, 1);
if (sr_sw_limits_check(&devc->limits))
sr_dev_acquisition_stop(sdi);
return TRUE;
}