scpi-dmm: run OPC queries immediately before essential commands

[libsigrok.git] / src / hardware / hp-3478a / protocol.c

diff --git a/src/hardware/hp-3478a/protocol.c b/src/hardware/hp-3478a/protocol.c
index 2871db767c38cf806a688b428df106fa2745445a..3ddce5884aa1bddd72a199f4823bae3e2cde5f2c 100644 (file)
--- a/src/hardware/hp-3478a/protocol.c
+++ b/src/hardware/hp-3478a/protocol.c
@@ -38,46 +38,27 @@ static const struct {
 
 static int set_mq_volt(struct sr_scpi_dev_inst *scpi, enum sr_mqflag flags)
 {
-       const char *cmd;
-
        if ((flags & SR_MQFLAG_AC) != SR_MQFLAG_AC &&
                (flags & SR_MQFLAG_DC) != SR_MQFLAG_DC)
                return SR_ERR_NA;
 
-       if ((flags & SR_MQFLAG_AC) == SR_MQFLAG_AC)
-               cmd = "F2";
-       else
-               cmd = "F1";
-
-       return sr_scpi_send(scpi, "%s", cmd);
+       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)
 {
-       const char *cmd;
-
        if ((flags & SR_MQFLAG_AC) != SR_MQFLAG_AC &&
                (flags & SR_MQFLAG_DC) != SR_MQFLAG_DC)
                return SR_ERR_NA;
 
-       if (flags & SR_MQFLAG_AC)
-               cmd = "F6";
-       else
-               cmd = "F5";
-
-       return sr_scpi_send(scpi, "%s", cmd);
+       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)
 {
-       const char *cmd;
-
-       if (flags & SR_MQFLAG_FOUR_WIRE)
-               cmd = "F4";
-       else
-               cmd = "F3";
-
-       return sr_scpi_send(scpi, "%s", cmd);
+       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,
@@ -110,81 +91,86 @@ SR_PRIV int hp_3478a_set_mq(const struct sr_dev_inst *sdi, enum sr_mq mq,
 
 static int parse_range_vdc(struct dev_context *devc, uint8_t range_byte)
 {
-       if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_30MV) {
+       if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_30MV)
                devc->enc_digits = devc->spec_digits - 2;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_300MV) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_300MV)
                devc->enc_digits = devc->spec_digits - 3;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_3V) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_3V)
                devc->enc_digits = devc->spec_digits - 1;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_30V) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_30V)
                devc->enc_digits = devc->spec_digits - 2;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_300V) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VDC_300V)
                devc->enc_digits = devc->spec_digits - 3;
-       } else {
+       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) {
+       if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_300MV)
                devc->enc_digits = devc->spec_digits - 3;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_3V) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_3V)
                devc->enc_digits = devc->spec_digits - 1;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_30V) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_30V)
                devc->enc_digits = devc->spec_digits - 2;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_300V) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_VAC_300V)
                devc->enc_digits = devc->spec_digits - 3;
-       } else {
+       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) {
+       if ((range_byte & SB1_RANGE_BLOCK) == RANGE_A_300MA)
                devc->enc_digits = devc->spec_digits - 3;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_A_3A) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_A_3A)
                devc->enc_digits = devc->spec_digits - 1;
-       } else {
+       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) {
+       if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_30R)
                devc->enc_digits = devc->spec_digits - 2;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_300R) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_300R)
                devc->enc_digits = devc->spec_digits - 3;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_3KR) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_3KR)
                devc->enc_digits = devc->spec_digits - 1;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_30KR) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_30KR)
                devc->enc_digits = devc->spec_digits - 2;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_300KR) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_300KR)
                devc->enc_digits = devc->spec_digits - 3;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_3MR) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_3MR)
                devc->enc_digits = devc->spec_digits - 1;
-       } else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_30MR) {
+       else if ((range_byte & SB1_RANGE_BLOCK) == RANGE_OHM_30MR)
                devc->enc_digits = devc->spec_digits - 2;
-       } else {
+       else
                return SR_ERR_DATA;
-       }
 
        return SR_OK;
 }
 
 static int parse_function_byte(struct dev_context *devc, uint8_t function_byte)
 {
-       devc->measurement_mq_flags = 0;
+       /* 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;
        if ((function_byte & SB1_FUNCTION_BLOCK) == FUNCTION_VDC) {
                devc->measurement_mq = SR_MQ_VOLTAGE;
                devc->measurement_mq_flags |= SR_MQFLAG_DC;
@@ -220,15 +206,6 @@ static int parse_function_byte(struct dev_context *devc, uint8_t function_byte)
                parse_range_ohm(devc, function_byte);
        }
 
-       /* Digits / Resolution */
-       if ((function_byte & SB1_DIGITS_BLOCK) == DIGITS_5_5) {
-               devc->spec_digits = 5;
-       } else if ((function_byte & SB1_DIGITS_BLOCK) == DIGITS_4_5) {
-               devc->spec_digits = 4;
-       } else if ((function_byte & SB1_DIGITS_BLOCK) == DIGITS_3_5) {
-               devc->spec_digits = 3;
-       }
-
        return SR_OK;
 }