X-Git-Url: http://sigrok.org/gitweb/?a=blobdiff_plain;f=src%2Fhardware%2Fasix-sigma%2Fprotocol.c;h=93d2623951e565f099ab68cc02e4af8ac66ccf32;hb=2142a79b53e7fb2d9d050c382b624820601c1bd6;hp=e2c34e5c9169699df381d5b8fecbbab3e8685849;hpb=8ebad343709aad6ef4d5aa83a2633690ef313de5;p=libsigrok.git

diff --git a/src/hardware/asix-sigma/protocol.c b/src/hardware/asix-sigma/protocol.c
index e2c34e5c..93d26239 100644
--- a/src/hardware/asix-sigma/protocol.c
+++ b/src/hardware/asix-sigma/protocol.c
@@ -168,11 +168,17 @@ static int sigma_read_pos(uint32_t *stoppos, uint32_t *triggerpos,
 	*triggerpos = result[0] | (result[1] << 8) | (result[2] << 16);
 	*stoppos = result[3] | (result[4] << 8) | (result[5] << 16);
 
-	/* Not really sure why this must be done, but according to spec. */
+	/*
+	 * These "position" values point to after the event (end of
+	 * capture data, trigger condition matched). This is why they
+	 * get decremented here. Sample memory consists of 512-byte
+	 * chunks with meta data in the upper 64 bytes. Thus when the
+	 * decrements takes us into this upper part of the chunk, then
+	 * further move backwards to the end of the chunk's data part.
+	 */
 	if ((--*stoppos & 0x1ff) == 0x1ff)
 		*stoppos -= 64;
-
-	if ((*--triggerpos & 0x1ff) == 0x1ff)
+	if ((--*triggerpos & 0x1ff) == 0x1ff)
 		*triggerpos -= 64;
 
 	return 1;
@@ -1009,14 +1015,13 @@ static int download_capture(struct sr_dev_inst *sdi)
 
 	devc = sdi->priv;
 	dl_events_in_line = 64 * 7;
-	trg_line = ~0;
-	trg_event = ~0;
 
 	dram_line = g_try_malloc0(chunks_per_read * sizeof(*dram_line));
 	if (!dram_line)
 		return FALSE;
 
 	sr_info("Downloading sample data.");
+	devc->state.state = SIGMA_DOWNLOAD;
 
 	/*
 	 * Ask the hardware to stop data acquisition. Reception of the
@@ -1037,6 +1042,8 @@ static int download_capture(struct sr_dev_inst *sdi)
 
 	/* Check if trigger has fired. */
 	modestatus = sigma_get_register(READ_MODE, devc);
+	trg_line = ~0;
+	trg_event = ~0;
 	if (modestatus & RMR_TRIGGERED) {
 		trg_line = triggerpos >> 9;
 		trg_event = triggerpos & 0x1ff;
@@ -1097,13 +1104,13 @@ static int download_capture(struct sr_dev_inst *sdi)
 
 		dl_lines_done += dl_lines_curr;
 	}
+	g_free(dram_line);
 
 	std_session_send_df_end(sdi);
 
+	devc->state.state = SIGMA_IDLE;
 	sr_dev_acquisition_stop(sdi);
 
-	g_free(dram_line);
-
 	return TRUE;
 }
 
@@ -1146,6 +1153,14 @@ SR_PRIV int sigma_receive_data(int fd, int revents, void *cb_data)
 	if (devc->state.state == SIGMA_IDLE)
 		return TRUE;
 
+	/*
+	 * When the application has requested to stop the acquisition,
+	 * then immediately start downloading sample data. Otherwise
+	 * keep checking configured limits which will terminate the
+	 * acquisition and initiate download.
+	 */
+	if (devc->state.state == SIGMA_STOPPING)
+		return download_capture(sdi);
 	if (devc->state.state == SIGMA_CAPTURE)
 		return sigma_capture_mode(sdi);