diff --git a/src/hardware/hantek-4032l/api.c b/src/hardware/hantek-4032l/api.c
index 97e9979b..33c55c69 100644
--- a/src/hardware/hantek-4032l/api.c
+++ b/src/hardware/hantek-4032l/api.c
@@ -35,7 +35,7 @@ static const uint32_t drvopts[] = {
 
 static const uint32_t devopts[] = {
 	SR_CONF_SAMPLERATE | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
-	SR_CONF_CAPTURE_RATIO | SR_CONF_GET | SR_CONF_SET,
+	SR_CONF_CAPTURE_RATIO | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
 	SR_CONF_LIMIT_SAMPLES | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
 	SR_CONF_TRIGGER_MATCH | SR_CONF_LIST,
 	SR_CONF_CONN | SR_CONF_GET,
@@ -213,7 +213,6 @@ static GSList *scan(struct sr_dev_driver *di, GSList *options)
 		devc->cmd_pkt.pwm_a = h4032l_voltage2pwm(2.5);
 		devc->cmd_pkt.pwm_b = h4032l_voltage2pwm(2.5);
 		devc->cmd_pkt.sample_size = 16384;
-		devc->cmd_pkt.pre_trigger_size = 1024;
 
 		devc->status = H4032L_STATUS_IDLE;
 
@@ -342,9 +341,15 @@ static int config_set(uint32_t key, GVariant *data,
 			cmd_pkt->sample_rate = i;
 			break;
 		}
-	case SR_CONF_CAPTURE_RATIO:
-		devc->capture_ratio = g_variant_get_uint64(data);
-		break;
+	case SR_CONF_CAPTURE_RATIO: {
+			uint64_t capture_ratio = g_variant_get_uint64(data);
+			if (capture_ratio > 99) {
+				sr_err("Invalid capture ratio.");
+				return SR_ERR;
+			}
+			devc->capture_ratio = capture_ratio;
+			break;
+		}
 	case SR_CONF_LIMIT_SAMPLES: {
 			uint64_t number_samples = g_variant_get_uint64(data);
 			number_samples += 511;
@@ -409,9 +414,11 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi)
 	/* Initialize variables. */
 	devc->acq_aborted = FALSE;
 	devc->submitted_transfers = 0;
+	devc->sent_samples = 0;
 
 	/* Calculate packet ratio. */
 	cmd_pkt->pre_trigger_size = (cmd_pkt->sample_size * devc->capture_ratio) / 100;
+	devc->trigger_pos = cmd_pkt->pre_trigger_size;
 
 	cmd_pkt->trig_flags.enable_trigger1 = 0;
 	cmd_pkt->trig_flags.enable_trigger2 = 0;
diff --git a/src/hardware/hantek-4032l/protocol.c b/src/hardware/hantek-4032l/protocol.c
index 5aa35de4..a166c0a1 100644
--- a/src/hardware/hantek-4032l/protocol.c
+++ b/src/hardware/hantek-4032l/protocol.c
@@ -101,6 +101,48 @@ static void resubmit_transfer(struct libusb_transfer *transfer)
 	free_transfer(transfer);
 }
 
+static void send_data(struct sr_dev_inst *sdi,
+	uint32_t *data, size_t sample_count)
+{
+	struct dev_context *devc = sdi->priv;
+	struct sr_datafeed_logic logic = {
+		.length = sample_count * sizeof(uint32_t),
+		.unitsize = sizeof(uint32_t),
+		.data = data
+	};
+	const struct sr_datafeed_packet packet = {
+		.type = SR_DF_LOGIC,
+		.payload = &logic
+	};
+	const struct sr_datafeed_packet trig = {
+		.type = SR_DF_TRIGGER,
+		.payload = NULL
+	};
+	size_t trigger_offset;
+
+	if (devc->trigger_pos >= devc->sent_samples &&
+		devc->trigger_pos < (devc->sent_samples + sample_count)) {
+		/* Get trigger position. */
+		trigger_offset = devc->trigger_pos - devc->sent_samples;
+		logic.length = trigger_offset * sizeof(uint32_t);
+		if (logic.length)
+			sr_session_send(sdi, &packet);
+
+		/* Send trigger position. */
+		sr_session_send(sdi, &trig);
+
+		/* Send rest of data. */
+		logic.length = (sample_count-trigger_offset) * sizeof(uint32_t);
+		logic.data = data + trigger_offset;
+		if (logic.length)
+			sr_session_send(sdi, &packet);
+	} else {
+		sr_session_send(sdi, &packet);
+	}
+
+	devc->sent_samples += sample_count;
+}
+
 SR_PRIV int h4032l_receive_data(int fd, int revents, void *cb_data)
 {
 	struct timeval tv;
@@ -119,11 +161,9 @@ SR_PRIV int h4032l_receive_data(int fd, int revents, void *cb_data)
 
 void LIBUSB_CALL h4032l_data_transfer_callback(struct libusb_transfer *transfer)
 {
-	const struct sr_dev_inst *sdi = transfer->user_data;
-	struct dev_context *devc = sdi->priv;
+	struct sr_dev_inst *const sdi = transfer->user_data;
+	struct dev_context *const devc = sdi->priv;
 	uint32_t max_samples = transfer->actual_length / sizeof(uint32_t);
-	struct sr_datafeed_packet packet;
-	struct sr_datafeed_logic logic;
 	uint32_t *buffer;
 	uint32_t number_samples;
 
@@ -150,12 +190,7 @@ void LIBUSB_CALL h4032l_data_transfer_callback(struct libusb_transfer *transfer)
 	number_samples = (devc->remaining_samples < max_samples) ?
 			  devc->remaining_samples : max_samples;
 	devc->remaining_samples -= number_samples;
-	packet.type = SR_DF_LOGIC;
-	packet.payload = &logic;
-	logic.length = number_samples * sizeof(uint32_t);
-	logic.unitsize = sizeof(uint32_t);
-	logic.data = buffer;
-	sr_session_send(sdi, &packet);
+	send_data(sdi, buffer, number_samples);
 	sr_dbg("Remaining: %d %08X %08X.", devc->remaining_samples,
 		buffer[0], buffer[1]);
 
@@ -177,15 +212,13 @@ void LIBUSB_CALL h4032l_data_transfer_callback(struct libusb_transfer *transfer)
 
 void LIBUSB_CALL h4032l_usb_callback(struct libusb_transfer *transfer)
 {
-	const struct sr_dev_inst *sdi = transfer->user_data;
-	struct dev_context *devc = sdi->priv;
+	struct sr_dev_inst *const sdi = transfer->user_data;
+	struct dev_context *const devc = sdi->priv;
 	struct sr_usb_dev_inst *usb = sdi->conn;
 	gboolean cmd = FALSE;
 	uint32_t max_samples = transfer->actual_length / sizeof(uint32_t);
 	uint32_t *buffer;
 	struct h4032l_status_packet *status;
-	struct sr_datafeed_packet packet;
-	struct sr_datafeed_logic logic;
 	uint32_t number_samples;
 	int ret;
 
@@ -259,12 +292,7 @@ void LIBUSB_CALL h4032l_usb_callback(struct libusb_transfer *transfer)
 		number_samples = (devc->remaining_samples < max_samples) ?
 				  devc->remaining_samples : max_samples;
 		devc->remaining_samples -= number_samples;
-		packet.type = SR_DF_LOGIC;
-		packet.payload = &logic;
-		logic.length = number_samples * sizeof(uint32_t);
-		logic.unitsize = sizeof(uint32_t);
-		logic.data = buffer;
-		sr_session_send(sdi, &packet);
+		send_data(sdi, buffer, number_samples);
 		sr_dbg("Remaining: %d %08X %08X.", devc->remaining_samples,
 		       buffer[0], buffer[1]);
 		break;
diff --git a/src/hardware/hantek-4032l/protocol.h b/src/hardware/hantek-4032l/protocol.h
index 0a2eeece..8665c8f0 100644
--- a/src/hardware/hantek-4032l/protocol.h
+++ b/src/hardware/hantek-4032l/protocol.h
@@ -126,6 +126,7 @@ struct h4032l_cmd_pkt {
 
 struct dev_context {
 	enum h4032l_status status;
+	unsigned int sent_samples;
 	int submitted_transfers;
 	uint32_t remaining_samples;
 	gboolean acq_aborted;
@@ -134,6 +135,7 @@ struct dev_context {
 	struct libusb_transfer **transfers;
 	uint8_t buffer[512];
 	uint64_t capture_ratio;
+	uint32_t trigger_pos;
 	uint32_t fpga_version;
 };