Set an RC status flag so that we can read out the RC status in parallel to the RC data

src/modules/px4iofirmware/controls.c

@@ -291,6 +291,7 @@ controls_tick() {
 
 		/* set RC OK flag, as we got an update */
 		r_status_flags |= PX4IO_P_STATUS_FLAGS_RC_OK;
+		r_raw_rc_flags |= PX4IO_P_RAW_RC_FLAGS_RC_OK;
 
 		/* if we have enough channels (5) to control the vehicle, the mapping is ok */
 		if (assigned_channels > 4) {
@@ -336,6 +337,9 @@ controls_tick() {
 			PX4IO_P_STATUS_FLAGS_OVERRIDE |
 			PX4IO_P_STATUS_FLAGS_RC_OK);
 
+		/* flag raw RC as lost */
+		r_raw_rc_flags &= ~(PX4IO_P_RAW_RC_FLAGS_RC_OK);
+
 		/* Mark all channels as invalid, as we just lost the RX */
 		r_rc_valid = 0;
 
@@ -405,8 +409,9 @@ ppm_input(uint16_t *values, uint16_t *num_values, uint16_t *frame_len)
 		if (*num_values > PX4IO_RC_INPUT_CHANNELS)
 			*num_values = PX4IO_RC_INPUT_CHANNELS;
 
-		for (unsigned i = 0; i < *num_values; i++)
+		for (unsigned i = 0; i < *num_values; i++) {
 			values[i] = ppm_buffer[i];
+		}
 
 		/* clear validity */
 		ppm_last_valid_decode = 0;

src/modules/px4iofirmware/protocol.h

@@ -142,6 +142,7 @@
 #define PX4IO_P_RAW_RC_FLAGS_FAILSAFE		(1 << 1) /* receiver is in failsafe mode */
 #define PX4IO_P_RAW_RC_FLAGS_RC_DSM11		(1 << 2) /* DSM decoding is 11 bit mode */
 #define PX4IO_P_RAW_RC_FLAGS_MAPPING_OK		(1 << 3) /* Channel mapping is ok */
+#define PX4IO_P_RAW_RC_FLAGS_RC_OK		(1 << 4) /* RC reception ok */
 
 #define PX4IO_P_RAW_RC_NRSSI			2	/* [2] Normalized RSSI value, 0: no reception, 255: perfect reception */
 #define PX4IO_P_RAW_RC_DATA			3	/* [1] + [2] Details about the RC source (PPM frame length, Spektrum protocol type) */