*/
if (ret == SR_OK) {
devc->cur_samplerate = samplerate;
- devc->period_ps = 1000000000000ULL / samplerate;
devc->samples_per_event = 16 / devc->num_channels;
devc->state.state = SIGMA_IDLE;
}
samples[2 * idx + 1] = (data >> 8) & 0xff;
}
+/*
+ * Local wrapper around sr_session_send() calls. Make sure to not send
+ * more samples to the session's datafeed than what was requested by a
+ * previously configured (optional) sample count.
+ */
+static void sigma_session_send(struct sr_dev_inst *sdi,
+ struct sr_datafeed_packet *packet)
+{
+ struct dev_context *devc;
+ struct sr_datafeed_logic *logic;
+ uint64_t send_now;
+
+ devc = sdi->priv;
+ if (devc->limit_samples) {
+ logic = (void *)packet->payload;
+ send_now = logic->length / logic->unitsize;
+ if (devc->sent_samples + send_now > devc->limit_samples) {
+ send_now = devc->limit_samples - devc->sent_samples;
+ logic->length = send_now * logic->unitsize;
+ }
+ if (!send_now)
+ return;
+ devc->sent_samples += send_now;
+ }
+
+ sr_session_send(sdi, packet);
+}
+
/*
* This size translates to: event count (1K events per cluster), times
* the sample width (unitsize, 16bits per event), times the maximum
logic.data = samples;
/*
- * First of all, send Sigrok a copy of the last sample from
- * previous cluster as many times as needed to make up for
- * the differential characteristics of data we get from the
- * Sigma. Sigrok needs one sample of data per period.
- *
- * One DRAM cluster contains a timestamp and seven samples,
- * the units of timestamp are "devc->period_ps" , the first
- * sample in the cluster happens at the time of the timestamp
- * and the remaining samples happen at timestamp +1...+6 .
+ * If this cluster is not adjacent to the previously received
+ * cluster, then send the appropriate number of samples with the
+ * previous values to the sigrok session. This "decodes RLE".
*/
for (ts = 0; ts < tsdiff; ts++) {
i = ts % 1024;
if ((i == 1023) || (ts == tsdiff - 1)) {
logic.length = (i + 1) * logic.unitsize;
for (j = 0; j < devc->samples_per_event; j++)
- sr_session_send(sdi, &packet);
+ sigma_session_send(sdi, &packet);
}
}
trig_count = trigger_offset * devc->samples_per_event;
packet.type = SR_DF_LOGIC;
logic.length = trig_count * logic.unitsize;
- sr_session_send(sdi, &packet);
+ sigma_session_send(sdi, &packet);
send_ptr += trig_count * logic.unitsize;
send_count -= trig_count;
}
packet.type = SR_DF_LOGIC;
logic.length = send_count * logic.unitsize;
logic.data = send_ptr;
- sr_session_send(sdi, &packet);
+ sigma_session_send(sdi, &packet);
}
ss->lastsample = sample;
uint8_t modestatus;
uint32_t i;
uint32_t dl_lines_total, dl_lines_curr, dl_lines_done;
+ uint32_t dl_first_line, dl_line;
uint32_t dl_events_in_line;
uint32_t trg_line, trg_event;
trg_event = triggerpos & 0x1ff;
}
+ devc->sent_samples = 0;
+
/*
- * Determine how many 1024b "DRAM lines" do we need to read from the
- * Sigma so we have a complete set of samples. Note that the last
- * line can be only partial, containing less than 64 clusters.
+ * Determine how many "DRAM lines" of 1024 bytes each we need to
+ * retrieve from the Sigma hardware, so that we have a complete
+ * set of samples. Note that the last line need not contain 64
+ * clusters, it might be partially filled only.
+ *
+ * When RMR_ROUND is set, the circular buffer in DRAM has wrapped
+ * around. Since the status of the very next line is uncertain in
+ * that case, we skip it and start reading from the next line. The
+ * circular buffer has 32K lines (0x8000).
*/
dl_lines_total = (stoppos >> 9) + 1;
-
+ if (modestatus & RMR_ROUND) {
+ dl_first_line = dl_lines_total + 1;
+ dl_lines_total = 0x8000 - 2;
+ } else {
+ dl_first_line = 0;
+ }
dl_lines_done = 0;
-
while (dl_lines_total > dl_lines_done) {
/* We can download only up-to 32 DRAM lines in one go! */
- dl_lines_curr = MIN(chunks_per_read, dl_lines_total);
+ dl_lines_curr = MIN(chunks_per_read, dl_lines_total - dl_lines_done);
- bufsz = sigma_read_dram(dl_lines_done, dl_lines_curr,
+ dl_line = dl_first_line + dl_lines_done;
+ dl_line %= 0x8000;
+ bufsz = sigma_read_dram(dl_line, dl_lines_curr,
(uint8_t *)dram_line, devc);
/* TODO: Check bufsz. For now, just avoid compiler warnings. */
(void)bufsz;
}
/*
- * Handle the Sigma when in CAPTURE mode. This function checks:
- * - Sampling time ended
- * - DRAM capacity overflow
- * This function triggers download of the samples from Sigma
- * in case either of the above conditions is true.
+ * Periodically check the Sigma status when in CAPTURE mode. This routine
+ * checks whether the configured sample count or sample time have passed,
+ * and will stop acquisition and download the acquired samples.
*/
static int sigma_capture_mode(struct sr_dev_inst *sdi)
{
struct dev_context *devc;
uint64_t running_msec;
- struct timeval tv;
- uint32_t stoppos, triggerpos;
+ uint64_t current_time;
devc = sdi->priv;
- /* Check if the selected sampling duration passed. */
- gettimeofday(&tv, 0);
- running_msec = (tv.tv_sec - devc->start_tv.tv_sec) * 1000 +
- (tv.tv_usec - devc->start_tv.tv_usec) / 1000;
+ /*
+ * Check if the selected sampling duration passed. Sample count
+ * limits are covered by this enforced timeout as well.
+ */
+ current_time = g_get_monotonic_time();
+ running_msec = (current_time - devc->start_time) / 1000;
if (running_msec >= devc->limit_msec)
return download_capture(sdi);
- /* Get the position in DRAM to which the FPGA is writing now. */
- sigma_read_pos(&stoppos, &triggerpos, devc);
- /* Test if DRAM is full and if so, download the data. */
- if ((stoppos >> 9) == 32767)
- return download_capture(sdi);
-
return TRUE;
}