]> sigrok.org Git - libsigrok.git/blobdiff - hardware/rigol-ds/protocol.c
rigol-ds: Support 4 analog channels.
[libsigrok.git] / hardware / rigol-ds / protocol.c
index 51cf25fa7d30ba505b334e896c55f5894073c070..4dec85b4fdcc90e26734c1f5fb83cd5dc2555c0a 100644 (file)
@@ -91,12 +91,21 @@ static int parse_int(const char *str, int *ret)
        return SR_OK;
 }
 
+/* Set the next event to wait for in rigol_ds_receive */
+static void rigol_ds_set_wait_event(struct dev_context *devc, enum wait_events event)
+{
+       if (event == WAIT_STOP)
+               devc->wait_status = 2;
+       else
+               devc->wait_status = 1;
+       devc->wait_event = event;
+}
+
 /*
- * Waiting for a trigger event will return a timeout after 2, 3 seconds in
- * order to not block the application.
+ * Waiting for a event will return a timeout after 2 to 3 seconds in order
+ * to not block the application.
  */
-
-static int rigol_ds2xx2_trigger_wait(const struct sr_dev_inst *sdi)
+static int rigol_ds_event_wait(const struct sr_dev_inst *sdi, char status1, char status2)
 {
        char buf[20];
        struct dev_context *devc;
@@ -109,14 +118,14 @@ static int rigol_ds2xx2_trigger_wait(const struct sr_dev_inst *sdi)
 
        /*
         * Trigger status may return:
-        * "TD"   - triggered
-        * "AUTO" - autotriggered
-        * "RUN"  - running
-        * "WAIT" - waiting for trigger
-        * "STOP" - stopped
+        * "TD" or "T'D" - triggered
+        * "AUTO"        - autotriggered
+        * "RUN"         - running
+        * "WAIT"        - waiting for trigger
+        * "STOP"        - stopped
         */
 
-       if (devc->trigger_wait_status == 1) {
+       if (devc->wait_status == 1) {
                do {
                        if (time(NULL) - start >= 3) {
                                sr_dbg("Timeout waiting for trigger");
@@ -125,11 +134,11 @@ static int rigol_ds2xx2_trigger_wait(const struct sr_dev_inst *sdi)
 
                        if (get_cfg(sdi, ":TRIG:STAT?", buf, sizeof(buf)) != SR_OK)
                                return SR_ERR;
-               } while (buf[0] == 'T' || buf[0] == 'A');
+               } while (buf[0] == status1 || buf[0] == status2);
 
-               devc->trigger_wait_status = 2;
+               devc->wait_status = 2;
        }
-       if (devc->trigger_wait_status == 2) {
+       if (devc->wait_status == 2) {
                do {
                        if (time(NULL) - start >= 3) {
                                sr_dbg("Timeout waiting for trigger");
@@ -138,71 +147,228 @@ static int rigol_ds2xx2_trigger_wait(const struct sr_dev_inst *sdi)
 
                        if (get_cfg(sdi, ":TRIG:STAT?", buf, sizeof(buf)) != SR_OK)
                                return SR_ERR;
-               } while (buf[0] != 'T' && buf[0] != 'A');
+               } while (buf[0] != status1 && buf[0] != status2);
 
-               devc->trigger_wait_status = 0;
+               rigol_ds_set_wait_event(devc, WAIT_NONE);
        }
 
        return SR_OK;
 }
 
 /*
- * This needs to wait for a new trigger event to ensure that sample data is
- * not returned twice.
+ * For live capture we need to wait for a new trigger event to ensure that
+ * sample data is not returned twice.
  *
  * Unfortunately this will never really work because for sufficiently fast
- * timebases it just can't catch the status changes.
+ * timebases and trigger rates it just can't catch the status changes.
  *
  * What would be needed is a trigger event register with autoreset like the
  * Agilents have. The Rigols don't seem to have anything like this.
  *
  * The workaround is to only wait for the trigger when the timebase is slow
  * enough. Of course this means that for faster timebases sample data can be
- * returned multiple times.
+ * returned multiple times, this effect is mitigated somewhat by sleeping
+ * for about one sweep time in that case.
  */
+static int rigol_ds_trigger_wait(const struct sr_dev_inst *sdi)
+{
+       struct dev_context *devc;
+       long s;
+
+       if (!(devc = sdi->priv))
+               return SR_ERR;
+
+       /* 
+        * If timebase < 50 msecs/DIV just sleep about one sweep time except
+        * for really fast sweeps.
+        */
+       if (devc->timebase < 0.0499)
+       {
+               if (devc->timebase > 0.99e-6) {
+                       /*
+                        * Timebase * num hor. divs * 85(%) * 1e6(usecs) / 100
+                        * -> 85 percent of sweep time
+                        */
+                       s = (devc->timebase * devc->model->num_horizontal_divs
+                            * 85e6) / 100L;
+                       sr_spew("Sleeping for %ld usecs instead of trigger-wait", s);
+                       g_usleep(s);
+               }
+               rigol_ds_set_wait_event(devc, WAIT_NONE);
+               return SR_OK;
+       } else {
+               return rigol_ds_event_wait(sdi, 'T', 'A');
+       }
+}
+
+/* Wait for scope to got to "Stop" in single shot mode */
+static int rigol_ds_stop_wait(const struct sr_dev_inst *sdi)
+{
+       return rigol_ds_event_wait(sdi, 'S', 'S');
+}
 
-SR_PRIV int rigol_ds2xx2_acquisition_start(const struct sr_dev_inst *sdi,
-                                          gboolean wait_for_trigger)
+/* Check that a single shot acquisition actually succeeded on the DS2000 */
+static int rigol_ds_check_stop(const struct sr_dev_inst *sdi)
 {
        struct dev_context *devc;
+       struct sr_probe *probe;
+       int tmp;
 
        if (!(devc = sdi->priv))
                return SR_ERR;
 
-       devc->channel_frame = devc->enabled_analog_probes->data;
+       probe = devc->channel_entry->data;
+
+       if (sr_scpi_send(sdi->conn, ":WAV:SOUR CHAN%d",
+                         probe->index + 1) != SR_OK)
+               return SR_ERR;
+       /* Check that the number of samples will be accepted */
+       if (sr_scpi_send(sdi->conn, ":WAV:POIN %d;*OPC", devc->analog_frame_size) != SR_OK)
+               return SR_ERR;
+       if (get_cfg_int(sdi, "*ESR?", &tmp) != SR_OK)
+               return SR_ERR;
+       /*
+        * If we get an "Execution error" the scope went from "Single" to
+        * "Stop" without actually triggering. There is no waveform
+        * displayed and trying to download one will fail - the scope thinks
+        * it has 1400 samples (like display memory) and the driver thinks
+        * it has a different number of samples.
+        *
+        * In that case just try to capture something again. Might still
+        * fail in interesting ways.
+        *
+        * Ain't firmware fun?
+        */
+       if (tmp & 0x10) {
+               sr_warn("Single shot acquisition failed, retrying...");
+               /* Sleep a bit, otherwise the single shot will often fail */
+               g_usleep(500000);
+               sr_scpi_send(sdi->conn, ":SING");
+               rigol_ds_set_wait_event(devc, WAIT_STOP);
+               return SR_ERR;
+       }
+
+       return SR_OK;
+}
 
-       sr_dbg("Starting acquisition on channel %d",
-                  devc->channel_frame->index + 1);
+/* Wait for enough data becoming available in scope output buffer */
+static int rigol_ds_block_wait(const struct sr_dev_inst *sdi)
+{
+       char buf[30];
+       struct dev_context *devc;
+       time_t start;
+       int len;
 
-       if (rigol_ds_send(sdi, ":WAV:FORM BYTE") != SR_OK)
+       if (!(devc = sdi->priv))
                return SR_ERR;
-       if (rigol_ds_send(sdi, ":WAV:SOUR CHAN%d",
-                                 devc->channel_frame->index + 1) != SR_OK)
+
+       start = time(NULL);
+
+       do {
+               if (time(NULL) - start >= 3) {
+                       sr_dbg("Timeout waiting for data block");
+                       return SR_ERR_TIMEOUT;
+               }
+
+               /*
+                * The scope copies data really slowly from sample
+                * memory to its output buffer, so try not to bother
+                * it too much with SCPI requests but don't wait too
+                * long for short sample frame sizes.
+                */
+               g_usleep(devc->analog_frame_size < 15000 ? 100000 : 1000000);
+
+               /* "READ,nnnn" (still working) or "IDLE,nnnn" (finished) */
+               if (get_cfg(sdi, ":WAV:STAT?", buf, sizeof(buf)) != SR_OK)
+                       return SR_ERR;
+
+               if (parse_int(buf + 5, &len) != SR_OK)
+                       return SR_ERR;
+       } while (buf[0] == 'R' && len < 1000000);
+
+       rigol_ds_set_wait_event(devc, WAIT_NONE);
+
+       return SR_OK;
+}
+
+/* Start capturing a new frameset */
+SR_PRIV int rigol_ds_capture_start(const struct sr_dev_inst *sdi)
+{
+       struct dev_context *devc;
+
+       if (!(devc = sdi->priv))
                return SR_ERR;
-       if (rigol_ds_send(sdi, ":WAV:MODE NORM") != SR_OK)
+
+       sr_dbg("Starting data capture for frameset %lu of %lu",
+              devc->num_frames + 1, devc->limit_frames);
+
+       if (sr_scpi_send(sdi->conn, ":WAV:FORM BYTE") != SR_OK)
                return SR_ERR;
+       if (devc->data_source == DATA_SOURCE_LIVE) {
+               if (sr_scpi_send(sdi->conn, ":WAV:MODE NORM") != SR_OK)
+                       return SR_ERR;
+               rigol_ds_set_wait_event(devc, WAIT_TRIGGER);
+       } else {
+               if (sr_scpi_send(sdi->conn, ":WAV:MODE RAW") != SR_OK)
+                       return SR_ERR;
+               if (sr_scpi_send(sdi->conn, ":SING", devc->analog_frame_size) != SR_OK)
+                       return SR_ERR;          
+               rigol_ds_set_wait_event(devc, WAIT_STOP);
+       }
 
-       devc->num_frame_bytes = 0;
-       devc->num_block_bytes = 0;
+       return SR_OK;
+}
 
-       /* only wait for trigger if timbase 50 msecs/DIV or slower */
-       if (wait_for_trigger && devc->timebase > 0.0499)
-       {
-               devc->trigger_wait_status = 1;
+/* Start reading data from the current channel */
+SR_PRIV int rigol_ds_channel_start(const struct sr_dev_inst *sdi)
+{
+       struct dev_context *devc;
+       struct sr_probe *probe;
+
+       if (!(devc = sdi->priv))
+               return SR_ERR;
+
+       probe = devc->channel_entry->data;
+
+       sr_dbg("Starting reading data from channel %d", probe->index + 1);
+
+       if (devc->model->protocol == PROTOCOL_LEGACY) {
+               if (probe->type == SR_PROBE_LOGIC) {
+                       if (sr_scpi_send(sdi->conn, ":WAV:DATA? DIG") != SR_OK)
+                               return SR_ERR;
+               } else {
+                       if (sr_scpi_send(sdi->conn, ":WAV:DATA? CHAN%d",
+                                       probe->index + 1) != SR_OK)
+                               return SR_ERR;
+               }
        } else {
-               devc->trigger_wait_status = 0;
+               if (sr_scpi_send(sdi->conn, ":WAV:SOUR CHAN%d",
+                                 probe->index + 1) != SR_OK)
+                       return SR_ERR;
+               if (devc->data_source != DATA_SOURCE_LIVE) {
+                       if (sr_scpi_send(sdi->conn, ":WAV:RES") != SR_OK)
+                               return SR_ERR;
+                       if (sr_scpi_send(sdi->conn, ":WAV:BEG") != SR_OK)
+                               return SR_ERR;
+                       rigol_ds_set_wait_event(devc, WAIT_BLOCK);
+               } else
+                       rigol_ds_set_wait_event(devc, WAIT_NONE);
        }
 
+       devc->num_frame_samples = 0;
+       devc->num_block_bytes = 0;
+
        return SR_OK;
 }
 
-static int rigol_ds2xx2_read_header(struct sr_serial_dev_inst *serial)
+/* Read the header of a data block */
+static int rigol_ds_read_header(struct sr_scpi_dev_inst *scpi)
 {
        char start[3], length[10];
        int len, tmp;
 
        /* Read the hashsign and length digit. */
-       tmp = serial_read(serial, start, 2);
+       tmp = sr_scpi_read(scpi, start, 2);
        start[2] = '\0';
        if (tmp != 2)
        {
@@ -217,7 +383,7 @@ static int rigol_ds2xx2_read_header(struct sr_serial_dev_inst *serial)
        len = atoi(start + 1);
 
        /* Read the data length. */
-       tmp = serial_read(serial, length, len);
+       tmp = sr_scpi_read(scpi, length, len);
        length[len] = '\0';
        if (tmp != len)
        {
@@ -238,15 +404,13 @@ static int rigol_ds2xx2_read_header(struct sr_serial_dev_inst *serial)
 SR_PRIV int rigol_ds_receive(int fd, int revents, void *cb_data)
 {
        struct sr_dev_inst *sdi;
-       struct sr_serial_dev_inst *serial;
+       struct sr_scpi_dev_inst *scpi;
        struct dev_context *devc;
        struct sr_datafeed_packet packet;
        struct sr_datafeed_analog analog;
        struct sr_datafeed_logic logic;
-       unsigned char buf[DS2000_ANALOG_WAVEFORM_SIZE];
        double vdiv, offset;
-       float data[DS2000_ANALOG_WAVEFORM_SIZE];
-       int len, i, waveform_size, vref;
+       int len, i, vref;
        struct sr_probe *probe;
 
        (void)fd;
@@ -257,70 +421,102 @@ SR_PRIV int rigol_ds_receive(int fd, int revents, void *cb_data)
        if (!(devc = sdi->priv))
                return TRUE;
 
-       serial = sdi->conn;
+       scpi = sdi->conn;
 
        if (revents == G_IO_IN) {
-               if (devc->trigger_wait_status > 0) {
-                       if (rigol_ds2xx2_trigger_wait(sdi) != SR_OK)
+               if (devc->model->protocol == PROTOCOL_IEEE488_2) {
+                       switch(devc->wait_event) {
+                       case WAIT_NONE:
+                               break;
+
+                       case WAIT_TRIGGER:
+                               if (rigol_ds_trigger_wait(sdi) != SR_OK)
+                                       return TRUE;
+                               if (rigol_ds_channel_start(sdi) != SR_OK)
+                                       return TRUE;
+                               break;
+
+                       case WAIT_BLOCK:
+                               if (rigol_ds_block_wait(sdi) != SR_OK)
+                                       return TRUE;
+                               break;
+
+                       case WAIT_STOP:
+                               if (rigol_ds_stop_wait(sdi) != SR_OK)
+                                       return TRUE;
+                               if (rigol_ds_check_stop(sdi) != SR_OK)
+                                       return TRUE;
+                               if (rigol_ds_channel_start(sdi) != SR_OK)
+                                       return TRUE;
                                return TRUE;
+
+                       default:
+                               sr_err("BUG: Unknown event target encountered");
+                       }
                }
 
-               if (devc->model->series == 2 && devc->num_block_bytes == 0) {
-                       sr_dbg("New block header expected");
-                       if (rigol_ds_send(sdi, ":WAV:DATA?") != SR_OK)
-                               return TRUE;
-                       len = rigol_ds2xx2_read_header(serial);
-                       if (len == -1)
-                               return TRUE;
-                       /* At slow timebases the scope sometimes returns
-                        * "short" data blocks, with apparently no way to
-                        * get the rest of the data. Discard these, the
-                        * complete data block will appear eventually.
-                        */
-                       if (len < DS2000_ANALOG_WAVEFORM_SIZE) {
-                               sr_dbg("Discarding short data block");
-                               serial_read(serial, buf, len + 1);
-                               return TRUE;
+               probe = devc->channel_entry->data;
+               
+               if (devc->num_block_bytes == 0) {
+                       if (devc->model->protocol == PROTOCOL_IEEE488_2) {
+                               sr_dbg("New block header expected");
+                               if (sr_scpi_send(sdi->conn, ":WAV:DATA?") != SR_OK)
+                                       return TRUE;
+                               len = rigol_ds_read_header(scpi);
+                               if (len == -1)
+                                       return TRUE;
+                               /* At slow timebases in live capture the DS2072
+                                * sometimes returns "short" data blocks, with
+                                * apparently no way to get the rest of the data.
+                                * Discard these, the complete data block will
+                                * appear eventually.
+                                */
+                               if (devc->data_source == DATA_SOURCE_LIVE
+                                               && (unsigned)len < devc->num_frame_samples) {
+                                       sr_dbg("Discarding short data block");
+                                       sr_scpi_read(scpi, (char *)devc->buffer, len + 1);
+                                       return TRUE;
+                               }
+                               devc->num_block_bytes = len;
+                       } else {
+                               devc->num_block_bytes = probe->type == SR_PROBE_ANALOG ?
+                                       (devc->model->series == RIGOL_VS5000 ?
+                                               VS5000_ANALOG_LIVE_WAVEFORM_SIZE :
+                                               DS1000_ANALOG_LIVE_WAVEFORM_SIZE) :
+                                       DIGITAL_WAVEFORM_SIZE;
                        }
-                       devc->num_block_bytes = len;
                        devc->num_block_read = 0;
                }
 
-               probe = devc->channel_frame;
-               if (devc->model->series == 2) {
-                       len = devc->num_block_bytes - devc->num_block_read;
-                       len = serial_read(serial, buf,
-                                       len < DS2000_ANALOG_WAVEFORM_SIZE ? len : DS2000_ANALOG_WAVEFORM_SIZE);
-               } else {
-                       waveform_size = probe->type == SR_PROBE_ANALOG ?
-                                       DS1000_ANALOG_WAVEFORM_SIZE : DIGITAL_WAVEFORM_SIZE;
-                       len = serial_read(serial, buf, waveform_size - devc->num_frame_bytes);
-               }
+               len = devc->num_block_bytes - devc->num_block_read;
+               len = sr_scpi_read(scpi, (char *)devc->buffer,
+                               len < ACQ_BUFFER_SIZE ? len : ACQ_BUFFER_SIZE);
+
                sr_dbg("Received %d bytes.", len);
                if (len == -1)
                        return TRUE;
 
-               if (devc->num_frame_bytes == 0) {
+               devc->num_block_read += len;
+
+               if (devc->num_frame_samples == 0) {
                        /* Start of a new frame. */
                        packet.type = SR_DF_FRAME_BEGIN;
                        sr_session_send(sdi, &packet);
                }
 
                if (probe->type == SR_PROBE_ANALOG) {
-                       if (devc->model->series == 2)
-                               devc->num_block_read += len;
                        vref = devc->vert_reference[probe->index];
                        vdiv = devc->vdiv[probe->index] / 25.6;
                        offset = devc->vert_offset[probe->index];
-                       if (devc->model->series == 2)
+                       if (devc->model->protocol == PROTOCOL_IEEE488_2)
                                for (i = 0; i < len; i++)
-                                       data[i] = ((int)buf[i] - vref) * vdiv - offset;
+                                       devc->data[i] = ((int)devc->buffer[i] - vref) * vdiv - offset;
                        else
                                for (i = 0; i < len; i++)
-                                       data[i] = (128 - buf[i]) * vdiv - offset;
+                                       devc->data[i] = (128 - devc->buffer[i]) * vdiv - offset;
                        analog.probes = g_slist_append(NULL, probe);
                        analog.num_samples = len;
-                       analog.data = data;
+                       analog.data = devc->data;
                        analog.mq = SR_MQ_VOLTAGE;
                        analog.unit = SR_UNIT_VOLT;
                        analog.mqflags = 0;
@@ -328,59 +524,65 @@ SR_PRIV int rigol_ds_receive(int fd, int revents, void *cb_data)
                        packet.payload = &analog;
                        sr_session_send(cb_data, &packet);
                        g_slist_free(analog.probes);
-
-                       if (devc->model->series == 2) {
-                               devc->num_frame_bytes += len;
-
-                               if (devc->num_frame_bytes < DS2000_ANALOG_WAVEFORM_SIZE)
-                                       /* Don't have the whole frame yet. */
-                                       return TRUE;
-
-                               sr_dbg("Frame completed, %d samples", devc->num_frame_bytes);
-                       } else {
-                               if (len != DS1000_ANALOG_WAVEFORM_SIZE)
-                                       /* Don't have the whole frame yet. */
-                                       return TRUE;
-                       }
                } else {
                        logic.length = len - 10;
                        logic.unitsize = 2;
-                       logic.data = buf + 10;
+                       logic.data = devc->buffer + 10;
                        packet.type = SR_DF_LOGIC;
                        packet.payload = &logic;
                        sr_session_send(cb_data, &packet);
+               }
 
-                       if (len != DIGITAL_WAVEFORM_SIZE)
-                               /* Don't have the whole frame yet. */
-                               return TRUE;
+               if (devc->num_block_read == devc->num_block_bytes) {
+                       sr_dbg("Block has been completed");
+                       if (devc->model->protocol == PROTOCOL_IEEE488_2) {
+                               /* Discard the terminating linefeed and prepare for
+                                  possible next block */
+                               sr_scpi_read(scpi, (char *)devc->buffer, 1);
+                               devc->num_block_bytes = 0;
+                               if (devc->data_source != DATA_SOURCE_LIVE)
+                                       rigol_ds_set_wait_event(devc, WAIT_BLOCK);
+                       }
+                       devc->num_block_read = 0;
+               } else {
+                       sr_dbg("%d of %d block bytes read", devc->num_block_read, devc->num_block_bytes);
                }
 
+               devc->num_frame_samples += len;
+
+               if (devc->num_frame_samples < (probe->type == SR_PROBE_ANALOG ?
+                                       devc->analog_frame_size : DIGITAL_WAVEFORM_SIZE))
+                       /* Don't have the whole frame yet. */
+                       return TRUE;
+
                /* End of the frame. */
+               sr_dbg("Frame completed, %d samples", devc->num_frame_samples);
                packet.type = SR_DF_FRAME_END;
                sr_session_send(sdi, &packet);
-               if (devc->model->series == 1)
-                       devc->num_frame_bytes = 0;
-
-               if (devc->enabled_analog_probes
-                               && devc->channel_frame == devc->enabled_analog_probes->data
-                               && devc->enabled_analog_probes->next != NULL) {
-                       /* We got the frame for the first analog channel, but
-                        * there's a second analog channel. */
-                       if (devc->model->series == 2) {
-                               /* Do not wait for trigger to try and keep channel data related. */
-                               rigol_ds2xx2_acquisition_start(sdi, FALSE);
-                       } else {
-                               devc->channel_frame = devc->enabled_analog_probes->next->data;
-                               rigol_ds_send(sdi, ":WAV:DATA? CHAN%c",
-                                               devc->channel_frame->name[2]);
-                       }
+               if (devc->model->protocol == PROTOCOL_IEEE488_2) {
+                       /* Signal end of data download to scope */
+                       if (devc->data_source != DATA_SOURCE_LIVE)
+                               /*
+                                * This causes a query error, without it switching
+                                * to the next channel causes an error. Fun with
+                                * firmware...
+                                */
+                               sr_scpi_send(sdi->conn, ":WAV:END");
+               }
+
+               if (probe->type == SR_PROBE_ANALOG
+                               && devc->channel_entry->next != NULL) {
+                       /* We got the frame for this analog channel, but
+                        * there's another analog channel. */
+                       devc->channel_entry = devc->channel_entry->next;
+                       rigol_ds_channel_start(sdi);
                } else {
-                       /* Done with both analog channels in this frame. */
+                       /* Done with all analog channels in this frame. */
                        if (devc->enabled_digital_probes
-                                       && devc->channel_frame != devc->enabled_digital_probes->data) {
+                                       && devc->channel_entry != devc->enabled_digital_probes) {
                                /* Now we need to get the digital data. */
-                               devc->channel_frame = devc->enabled_digital_probes->data;
-                               rigol_ds_send(sdi, ":WAV:DATA? DIG");
+                               devc->channel_entry = devc->enabled_digital_probes;
+                               rigol_ds_channel_start(sdi);
                        } else if (++devc->num_frames == devc->limit_frames) {
                                /* End of last frame. */
                                packet.type = SR_DF_END;
@@ -388,23 +590,15 @@ SR_PRIV int rigol_ds_receive(int fd, int revents, void *cb_data)
                                sdi->driver->dev_acquisition_stop(sdi, cb_data);
                        } else {
                                /* Get the next frame, starting with the first analog channel. */
-                               if (devc->model->series == 2) {
-                                       if (devc->enabled_analog_probes) {
-                                               /* Must wait for trigger because at
-                                                * slow timebases the scope will
-                                                * return old data otherwise. */
-                                               rigol_ds2xx2_acquisition_start(sdi, TRUE);
-                                       }
-                               } else {
-                                       if (devc->enabled_analog_probes) {
-                                               devc->channel_frame = devc->enabled_analog_probes->data;
-                                               rigol_ds_send(sdi, ":WAV:DATA? CHAN%c",
-                                                               devc->channel_frame->name[2]);
-                                       } else {
-                                               devc->channel_frame = devc->enabled_digital_probes->data;
-                                               rigol_ds_send(sdi, ":WAV:DATA? DIG");
-                                       }
-                               }
+                               if (devc->enabled_analog_probes)
+                                       devc->channel_entry = devc->enabled_analog_probes;
+                               else
+                                       devc->channel_entry = devc->enabled_digital_probes;
+
+                               if (devc->model->protocol == PROTOCOL_LEGACY)
+                                       rigol_ds_channel_start(sdi);
+                               else
+                                       rigol_ds_capture_start(sdi);
                        }
                }
        }
@@ -412,43 +606,24 @@ SR_PRIV int rigol_ds_receive(int fd, int revents, void *cb_data)
        return TRUE;
 }
 
-SR_PRIV int rigol_ds_send(const struct sr_dev_inst *sdi, const char *format, ...)
-{
-       va_list args;
-       char buf[256];
-       int len, out, ret;
-
-       va_start(args, format);
-       len = vsnprintf(buf, 255, format, args);
-       va_end(args);
-       strcat(buf, "\n");
-       len++;
-       out = serial_write(sdi->conn, buf, len);
-       buf[len - 1] = '\0';
-       if (out != len) {
-               sr_dbg("Only sent %d/%d bytes of '%s'.", out, len, buf);
-               ret = SR_ERR;
-       } else {
-               sr_spew("Sent '%s'.", buf);
-               ret = SR_OK;
-       }
-
-       return ret;
-}
-
 static int get_cfg(const struct sr_dev_inst *sdi, char *cmd, char *reply, size_t maxlen)
 {
        int len;
        struct dev_context *devc = sdi->priv;
+       struct sr_scpi_dev_inst *scpi = sdi->conn;
+       char *response;
 
-       if (rigol_ds_send(sdi, cmd) != SR_OK)
+       if (sr_scpi_send(scpi, cmd) != SR_OK)
                return SR_ERR;
 
-       if ((len = serial_read(sdi->conn, reply, maxlen - 1)) < 0)
+       if (sr_scpi_receive(scpi, &response) != SR_OK)
                return SR_ERR;
-       reply[len] = '\0';
 
-       if (devc->model->series == 2) {
+       g_strlcpy(reply, response, maxlen);
+       g_free(response);
+       len = strlen(reply);
+
+       if (devc->model->protocol == PROTOCOL_IEEE488_2) {
                /* get rid of trailing linefeed */
                if (len >= 1 && reply[len-1] == '\n')
                        reply[len-1] = '\0';
@@ -502,35 +677,36 @@ SR_PRIV int rigol_ds_get_dev_cfg(const struct sr_dev_inst *sdi)
 {
        struct dev_context *devc;
        char *t_s, *cmd;
-       int i, res;
+       unsigned int i;
+       int res;
 
        devc = sdi->priv;
 
        /* Analog channel state. */
-       if (get_cfg_string(sdi, ":CHAN1:DISP?", &t_s) != SR_OK)
-               return SR_ERR;
-       devc->analog_channels[0] = !strcmp(t_s, "ON") || !strcmp(t_s, "1");
-       g_free(t_s);
-       if (get_cfg_string(sdi, ":CHAN2:DISP?", &t_s) != SR_OK)
-               return SR_ERR;
-       devc->analog_channels[1] = !strcmp(t_s, "ON") || !strcmp(t_s, "1");
-       g_free(t_s);
-       sr_dbg("Current analog channel state CH1 %s CH2 %s",
-                       devc->analog_channels[0] ? "on" : "off",
-                       devc->analog_channels[1] ? "on" : "off");
+       for (i = 0; i < devc->model->analog_channels; i++) {
+               cmd = g_strdup_printf(":CHAN%d:DISP?", i + 1);
+               res = get_cfg_string(sdi, cmd, &t_s);
+               g_free(cmd);
+               if (res != SR_OK)
+                       return SR_ERR;
+               devc->analog_channels[i] = !strcmp(t_s, "ON") || !strcmp(t_s, "1");
+       }
+       sr_dbg("Current analog channel state:");
+       for (i = 0; i < devc->model->analog_channels; i++)
+               sr_dbg("CH%d %s", i + 1, devc->analog_channels[i] ? "on" : "off");
 
        /* Digital channel state. */
        if (devc->model->has_digital) {
                sr_dbg("Current digital channel state:");
                for (i = 0; i < 16; i++) {
-                       cmd = g_strdup_printf(":DIG%d:TURN?", i);
+                       cmd = g_strdup_printf(":DIG%d:TURN?", i + 1);
                        res = get_cfg_string(sdi, cmd, &t_s);
                        g_free(cmd);
                        if (res != SR_OK)
                                return SR_ERR;
                        devc->digital_channels[i] = !strcmp(t_s, "ON") ? TRUE : FALSE;
                        g_free(t_s);
-                       sr_dbg("D%d: %s", i, devc->digital_channels[i] ? "on" : "off");
+                       sr_dbg("D%d: %s", i + 1, devc->digital_channels[i] ? "on" : "off");
                }
        }
 
@@ -540,41 +716,52 @@ SR_PRIV int rigol_ds_get_dev_cfg(const struct sr_dev_inst *sdi)
        sr_dbg("Current timebase %g", devc->timebase);
 
        /* Vertical gain. */
-       if (get_cfg_float(sdi, ":CHAN1:SCAL?", &devc->vdiv[0]) != SR_OK)
-               return SR_ERR;
-       if (get_cfg_float(sdi, ":CHAN2:SCAL?", &devc->vdiv[1]) != SR_OK)
-               return SR_ERR;
-       sr_dbg("Current vertical gain CH1 %g CH2 %g", devc->vdiv[0], devc->vdiv[1]);
+       for (i = 0; i < devc->model->analog_channels; i++) {
+               cmd = g_strdup_printf(":CHAN%d:SCAL?", i + 1);
+               res = get_cfg_float(sdi, cmd, &devc->vdiv[i]);
+               g_free(cmd);
+               if (res != SR_OK)
+                       return SR_ERR;
+       }
+       sr_dbg("Current vertical gain:");
+       for (i = 0; i < devc->model->analog_channels; i++)
+               sr_dbg("CH%d %g", i + 1, devc->vdiv[i]);
 
-       if (devc->model->series == 2) {
+       sr_dbg("Current vertical reference:");
+       if (devc->model->protocol == PROTOCOL_IEEE488_2) {
                /* Vertical reference - not certain if this is the place to read it. */
-               if (rigol_ds_send(sdi, ":WAV:SOUR CHAN1") != SR_OK)
-                       return SR_ERR;
-               if (get_cfg_int(sdi, ":WAV:YREF?", &devc->vert_reference[0]) != SR_OK)
-                       return SR_ERR;
-               if (rigol_ds_send(sdi, ":WAV:SOUR CHAN2") != SR_OK)
-                       return SR_ERR;
-               if (get_cfg_int(sdi, ":WAV:YREF?", &devc->vert_reference[1]) != SR_OK)
-                       return SR_ERR;
-               sr_dbg("Current vertical reference CH1 %d CH2 %d",
-                               devc->vert_reference[0], devc->vert_reference[1]);
+               for (i = 0; i < devc->model->analog_channels; i++) {
+                       if (sr_scpi_send(sdi->conn, ":WAV:SOUR CHAN%d", i + 1) != SR_OK)
+                               return SR_ERR;
+                       if (get_cfg_int(sdi, ":WAV:YREF?", &devc->vert_reference[i]) != SR_OK)
+                               return SR_ERR;
+                       sr_dbg("CH%d %d", i + 1, devc->vert_reference[i]);
+               }
        }
 
        /* Vertical offset. */
-       if (get_cfg_float(sdi, ":CHAN1:OFFS?", &devc->vert_offset[0]) != SR_OK)
-               return SR_ERR;
-       if (get_cfg_float(sdi, ":CHAN2:OFFS?", &devc->vert_offset[1]) != SR_OK)
-               return SR_ERR;
-       sr_dbg("Current vertical offset CH1 %g CH2 %g", devc->vert_offset[0],
-                       devc->vert_offset[1]);
+       for (i = 0; i < devc->model->analog_channels; i++) {
+               cmd = g_strdup_printf(":CHAN%d:OFFS?", i + 1);
+               res = get_cfg_float(sdi, cmd, &devc->vert_offset[i]);
+               g_free(cmd);
+               if (res != SR_OK)
+                       return SR_ERR;
+       }
+       sr_dbg("Current vertical offset:");
+       for (i = 0; i < devc->model->analog_channels; i++)
+               sr_dbg("CH%d %g", i + 1, devc->vert_offset[i]);
 
        /* Coupling. */
-       if (get_cfg_string(sdi, ":CHAN1:COUP?", &devc->coupling[0]) != SR_OK)
-               return SR_ERR;
-       if (get_cfg_string(sdi, ":CHAN2:COUP?", &devc->coupling[1]) != SR_OK)
-               return SR_ERR;
-       sr_dbg("Current coupling CH1 %s CH2 %s", devc->coupling[0],
-                       devc->coupling[1]);
+       for (i = 0; i < devc->model->analog_channels; i++) {
+               cmd = g_strdup_printf(":CHAN%d:COUP?", i + 1);
+               res = get_cfg_string(sdi, cmd, &devc->coupling[i]);
+               g_free(cmd);
+               if (res != SR_OK)
+                       return SR_ERR;
+       }
+       sr_dbg("Current coupling:");
+       for (i = 0; i < devc->model->analog_channels; i++)
+               sr_dbg("CH%d %s", i + 1, devc->coupling[i]);
 
        /* Trigger source. */
        if (get_cfg_string(sdi, ":TRIG:EDGE:SOUR?", &devc->trigger_source) != SR_OK)