diff --git a/src/modules/systemlib/ppm_decode.c b/src/modules/systemlib/ppm_decode.c
deleted file mode 100644
index 06845a043b399435b7b529bdccef6906e9dc1714..0000000000000000000000000000000000000000
--- a/src/modules/systemlib/ppm_decode.c
+++ /dev/null
@@ -1,255 +0,0 @@
-/****************************************************************************
- *
- * Copyright (C) 2012 PX4 Development Team. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- * 3. Neither the name PX4 nor the names of its contributors may be
- * used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- ****************************************************************************/
-
-/**
- * @file ppm_decode.c
- *
- * PPM input decoder.
- */
-
-#include <px4_config.h>
-
-#include <stdint.h>
-#include <string.h>
-
-#include <drivers/drv_hrt.h>
-
-#include "ppm_decode.h"
-
-/*
- * PPM decoder tuning parameters.
- *
- * The PPM decoder works as follows.
- *
- * Initially, the decoder waits in the UNSYNCH state for two edges
- * separated by PPM_MIN_START. Once the second edge is detected,
- * the decoder moves to the ARM state.
- *
- * The ARM state expects an edge within PPM_MAX_PULSE_WIDTH, being the
- * timing mark for the first channel. If this is detected, it moves to
- * the INACTIVE state.
- *
- * The INACTIVE phase waits for and discards the next edge, as it is not
- * significant. Once the edge is detected, it moves to the ACTIVE stae.
- *
- * The ACTIVE state expects an edge within PPM_MAX_PULSE_WIDTH, and when
- * received calculates the time from the previous mark and records
- * this time as the value for the next channel.
- *
- * If at any time waiting for an edge, the delay from the previous edge
- * exceeds PPM_MIN_START the frame is deemed to have ended and the recorded
- * values are advertised to clients.
- */
-#define PPM_MAX_PULSE_WIDTH 500 /* maximum width of a pulse */
-#define PPM_MIN_CHANNEL_VALUE 800 /* shortest valid channel signal */
-#define PPM_MAX_CHANNEL_VALUE 2200 /* longest valid channel signal */
-#define PPM_MIN_START 2500 /* shortest valid start gap */
-
-/* Input timeout - after this interval we assume signal is lost */
-#define PPM_INPUT_TIMEOUT 100 * 1000 /* 100ms */
-
-/* Number of same-sized frames required to 'lock' */
-#define PPM_CHANNEL_LOCK 3 /* should be less than the input timeout */
-
-/* decoded PPM buffer */
-#define PPM_MIN_CHANNELS 4
-#define PPM_MAX_CHANNELS 12
-
-/*
- * Public decoder state
- */
-uint16_t ppm_buffer[PPM_MAX_CHANNELS];
-unsigned ppm_decoded_channels;
-hrt_abstime ppm_last_valid_decode;
-
-static uint16_t ppm_temp_buffer[PPM_MAX_CHANNELS];
-
-/* PPM decoder state machine */
-static struct {
- uint16_t last_edge; /* last capture time */
- uint16_t last_mark; /* last significant edge */
- unsigned next_channel;
- unsigned count_max;
- enum {
- UNSYNCH = 0,
- ARM,
- ACTIVE,
- INACTIVE
- } phase;
-} ppm;
-
-
-void
-ppm_input_init(unsigned count_max)
-{
- ppm_decoded_channels = 0;
- ppm_last_valid_decode = 0;
-
- memset(&ppm, 0, sizeof(ppm));
- ppm.count_max = count_max;
-}
-
-void
-ppm_input_decode(bool reset, unsigned count)
-{
- uint16_t width;
- uint16_t interval;
- unsigned i;
-
- /* if we missed an edge, we have to give up */
- if (reset) {
- goto error;
- }
-
- /* how long since the last edge? */
- width = count - ppm.last_edge;
-
- if (count < ppm.last_edge) {
- width += ppm.count_max; /* handle wrapped count */
- }
-
- ppm.last_edge = count;
-
- /*
- * If this looks like a start pulse, then push the last set of values
- * and reset the state machine.
- *
- * Note that this is not a "high performance" design; it implies a whole
- * frame of latency between the pulses being received and their being
- * considered valid.
- */
- if (width >= PPM_MIN_START) {
-
- /*
- * If the number of channels changes unexpectedly, we don't want
- * to just immediately jump on the new count as it may be a result
- * of noise or dropped edges. Instead, take a few frames to settle.
- */
- if (ppm.next_channel != ppm_decoded_channels) {
- static unsigned new_channel_count;
- static unsigned new_channel_holdoff;
-
- if (new_channel_count != ppm.next_channel) {
- /* start the lock counter for the new channel count */
- new_channel_count = ppm.next_channel;
- new_channel_holdoff = PPM_CHANNEL_LOCK;
-
- } else if (new_channel_holdoff > 0) {
- /* this frame matched the last one, decrement the lock counter */
- new_channel_holdoff--;
-
- } else {
- /* we have seen PPM_CHANNEL_LOCK frames with the new count, accept it */
- ppm_decoded_channels = new_channel_count;
- new_channel_count = 0;
- }
-
- } else {
- /* frame channel count matches expected, let's use it */
- if (ppm.next_channel > PPM_MIN_CHANNELS) {
- for (i = 0; i < ppm.next_channel; i++) {
- ppm_buffer[i] = ppm_temp_buffer[i];
- }
-
- ppm_last_valid_decode = hrt_absolute_time();
- }
- }
-
- /* reset for the next frame */
- ppm.next_channel = 0;
-
- /* next edge is the reference for the first channel */
- ppm.phase = ARM;
-
- return;
- }
-
- switch (ppm.phase) {
- case UNSYNCH:
- /* we are waiting for a start pulse - nothing useful to do here */
- return;
-
- case ARM:
-
- /* we expect a pulse giving us the first mark */
- if (width > PPM_MAX_PULSE_WIDTH) {
- goto error; /* pulse was too long */
- }
-
- /* record the mark timing, expect an inactive edge */
- ppm.last_mark = count;
- ppm.phase = INACTIVE;
- return;
-
- case INACTIVE:
- /* this edge is not interesting, but now we are ready for the next mark */
- ppm.phase = ACTIVE;
-
- /* note that we don't bother looking at the timing of this edge */
-
- return;
-
- case ACTIVE:
-
- /* we expect a well-formed pulse */
- if (width > PPM_MAX_PULSE_WIDTH) {
- goto error; /* pulse was too long */
- }
-
- /* determine the interval from the last mark */
- interval = count - ppm.last_mark;
- ppm.last_mark = count;
-
- /* if the mark-mark timing is out of bounds, abandon the frame */
- if ((interval < PPM_MIN_CHANNEL_VALUE) || (interval > PPM_MAX_CHANNEL_VALUE)) {
- goto error;
- }
-
- /* if we have room to store the value, do so */
- if (ppm.next_channel < PPM_MAX_CHANNELS) {
- ppm_temp_buffer[ppm.next_channel++] = interval;
- }
-
- ppm.phase = INACTIVE;
- return;
-
- }
-
- /* the state machine is corrupted; reset it */
-
-error:
- /* we don't like the state of the decoder, reset it and try again */
- ppm.phase = UNSYNCH;
- ppm_decoded_channels = 0;
-}
-
diff --git a/src/modules/systemlib/ppm_decode.h b/src/modules/systemlib/ppm_decode.h
index 5a1ad84da9aec033e14f4f04de6a9fe230257c37..5079def84c0981dd886662befb48ea5ad7d3ca82 100644
--- a/src/modules/systemlib/ppm_decode.h
+++ b/src/modules/systemlib/ppm_decode.h
@@ -61,26 +61,4 @@ __EXPORT extern uint16_t ppm_frame_length; /**< length of the decoded PPM fra
__EXPORT extern unsigned ppm_decoded_channels; /**< count of decoded channels */
__EXPORT extern hrt_abstime ppm_last_valid_decode; /**< timestamp of the last valid decode */
-/**
- * Initialise the PPM input decoder.
- *
- * @param count_max The maximum value of the counter passed to
- * ppm_input_decode, used to determine how to
- * handle counter wrap.
- */
-__EXPORT void ppm_input_init(unsigned count_max);
-
-/**
- * Inform the decoder of an edge on the PPM input.
- *
- * This function can be registered with the HRT as the PPM edge handler.
- *
- * @param reset If set, the edge detector has missed one or
- * more edges and the decoder needs to be reset.
- * @param count A microsecond timestamp corresponding to the
- * edge, in the range 0-count_max. This value
- * is expected to wrap.
- */
-__EXPORT void ppm_input_decode(bool reset, unsigned count);
-
__END_DECLS
\ No newline at end of file