cem-dt-885x: Send last measurement at normal rate in hold mode

[libsigrok.git] / hardware / cem-dt-885x / protocol.c

diff --git a/hardware/cem-dt-885x/protocol.c b/hardware/cem-dt-885x/protocol.c
index 8b09d3242eeec0bb58f775924522a356e6c37313..c9d0c89e580ad07e3844247ceaf14e3bb829496c 100644 (file)
--- a/hardware/cem-dt-885x/protocol.c
+++ b/hardware/cem-dt-885x/protocol.c
@@ -117,13 +117,26 @@ static void process_mset(const struct sr_dev_inst *sdi)
                fvalue += (devc->buf[0] & 0x0f) * 10;
                fvalue += ((devc->buf[1] & 0xf0) >> 4);
                fvalue += (devc->buf[1] & 0x0f) / 10.0;
+               devc->last_spl = fvalue;
+               break;
+       case TOKEN_MEAS_WAS_READOUT:
+       case TOKEN_MEAS_WAS_BARGRAPH:
+               if (devc->cur_mqflags & (SR_MQFLAG_MAX | SR_MQFLAG_MIN)) {
+                       if (devc->token == TOKEN_MEAS_WAS_BARGRAPH) {
+                               /* The device still sends bargraph measurements even
+                                * when in max/min hold mode. Suppress them here, unless
+                                * they're readout values. This duplicates the behavior
+                                * of the device display exactly. */
+                               break;
+                       }
+               }
                memset(&analog, 0, sizeof(struct sr_datafeed_analog));
                analog.mq = SR_MQ_SOUND_PRESSURE_LEVEL;
                analog.mqflags = devc->cur_mqflags;
                analog.unit = SR_UNIT_DECIBEL_SPL;
                analog.probes = sdi->probes;
                analog.num_samples = 1;
-               analog.data = &fvalue;
+               analog.data = &devc->last_spl;
                packet.type = SR_DF_ANALOG;
                packet.payload = &analog;
                sr_session_send(devc->cb_data, &packet);
@@ -138,8 +151,6 @@ static void process_mset(const struct sr_dev_inst *sdi)
        case TOKEN_STORE_FULL:
        case TOKEN_RECORDING_ON:
        case TOKEN_RECORDING_OFF:
-       case TOKEN_MEAS_WAS_READOUT:
-       case TOKEN_MEAS_WAS_BARGRAPH:
        case TOKEN_BATTERY_OK:
        case TOKEN_BATTERY_LOW:
        case TOKEN_MEAS_RANGE_OK:
@@ -158,6 +169,7 @@ static void process_mset(const struct sr_dev_inst *sdi)
 static void process_byte(const struct sr_dev_inst *sdi, const unsigned char c)
 {
        struct dev_context *devc;
+       gint64 cur_time;
        int len;
 
        if (!(devc = sdi->priv))
@@ -167,14 +179,26 @@ static void process_byte(const struct sr_dev_inst *sdi, const unsigned char c)
                /* Device is in hold mode */
                devc->cur_mqflags |= SR_MQFLAG_HOLD;
 
-               /* TODO: send out the last measurement at the same
-                * rate as it normally gets sent */
+               if (devc->hold_last_sent == 0) {
+                       /* First hold notification. */
+                       devc->hold_last_sent = g_get_monotonic_time();
+                       /* When the device leaves hold mode, it starts from scratch. */
+                       devc->state = ST_INIT;
+               } else {
+                       cur_time = g_get_monotonic_time();
+                       if (cur_time - devc->hold_last_sent > HOLD_REPEAT_INTERVAL) {
+                               /* Force the last measurement out again. */
+                               devc->cmd = 0xa5;
+                               devc->token = TOKEN_MEAS_WAS_READOUT;
+                               process_mset(sdi);
+                               devc->hold_last_sent = cur_time;
+                       }
+               }
 
-               /* When the device leaves hold mode, it starts from scratch. */
-               devc->state = ST_INIT;
                return;
        }
        devc->cur_mqflags &= ~SR_MQFLAG_HOLD;
+       devc->hold_last_sent = 0;
 
        if (devc->state == ST_INIT) {
                if (c == 0xa5) {