demo: Fix analog output at low samplerate.

diff --git a/src/hardware/demo/demo.c b/src/hardware/demo/demo.c
index 42d1d7888d4f02ecd4d181c6bd7fdb7f068d98a4..21715ea0826e52fcbdd19dc05976ae51b8793f02 100644 (file)
--- a/src/hardware/demo/demo.c
+++ b/src/hardware/demo/demo.c
@@ -671,6 +671,7 @@ static int prepare_data(int fd, int revents, void *cb_data)
        struct sr_datafeed_packet packet;
        struct sr_datafeed_logic logic;
        struct analog_gen *ag;
+       int ag_pattern_pos;
        GHashTableIter iter;
        void *value;
        uint64_t logic_todo, analog_todo, expected_samplenum, analog_sent, sending_now;
@@ -722,13 +723,9 @@ static int prepare_data(int fd, int revents, void *cb_data)
                                ag = value;
                                packet.type = SR_DF_ANALOG;
                                packet.payload = &ag->packet;
-
-                               /* FIXME we should make sure we output a whole
-                                * period of data before we send out again the
-                                * beginning of our buffer. A ring buffer would
-                                * help here as well */
-
-                               sending_now = MIN(analog_todo, ag->num_samples);
+                               ag_pattern_pos = devc->analog_counter % ag->num_samples;
+                               sending_now = MIN(analog_todo, ag->num_samples-ag_pattern_pos);
+                               ag->packet.data = ag->pattern_data + ag_pattern_pos;
                                ag->packet.num_samples = sending_now;
                                sr_session_send(sdi, &packet);