RC_Protocol: add detection of sumd protocol over sigread

libraries/AP_RCProtocol/AP_RCProtocol.cpp

@@ -20,6 +20,8 @@
 #include "AP_RCProtocol_DSM.h"
 #include "AP_RCProtocol_SBUS.h"
 #include "AP_RCProtocol_SBUS_NI.h"
+#include "AP_RCProtocol_SUMD.h"
+#include "AP_RCProtocol_SUMD_NI.h"
 
 void AP_RCProtocol::init()
 {
@@ -27,6 +29,7 @@ void AP_RCProtocol::init()
     backend[AP_RCProtocol::SBUS] = new AP_RCProtocol_SBUS(*this);
     backend[AP_RCProtocol::SBUS_NI] = new AP_RCProtocol_SBUS_NI(*this);
     backend[AP_RCProtocol::DSM] = new AP_RCProtocol_DSM(*this);
+    backend[AP_RCProtocol::SUMD] = new AP_RCProtocol_SUMD(*this);
 }
 
 void AP_RCProtocol::process_pulse(uint32_t width_s0, uint32_t width_s1)
@@ -55,6 +58,32 @@ void AP_RCProtocol::process_pulse(uint32_t width_s0, uint32_t width_s1)
     }
 }
 
+void AP_RCProtocol::process_byte(uint8_t byte)
+{
+    uint32_t now = AP_HAL::millis();
+    // first try current protocol
+    if (_detected_protocol != AP_RCProtocol::NONE && now - _last_input_ms < 200) {
+        backend[_detected_protocol]->process_byte(byte);
+        if (backend[_detected_protocol]->new_input()) {
+            _new_input = true;
+            _last_input_ms = AP_HAL::millis();
+        }
+        return;
+    }
+
+    // otherwise scan all protocols
+    for (uint8_t i = 0; i < AP_RCProtocol::NONE; i++) {
+        if (backend[i] != nullptr) {
+            backend[i]->process_byte(byte);
+            if (backend[i]->new_input()) {
+                _new_input = true;
+                _detected_protocol = (enum AP_RCProtocol::rcprotocol_t)i;
+                _last_input_ms = AP_HAL::millis();
+            }
+        }
+    }
+}
+
 bool AP_RCProtocol::new_input()
 {
     bool ret = _new_input;

libraries/AP_RCProtocol/AP_RCProtocol.h

@@ -18,7 +18,7 @@
 #include <AP_HAL/AP_HAL.h>
 #include <AP_Common/AP_Common.h>
 
-#define MAX_RCIN_CHANNELS 16
+#define MAX_RCIN_CHANNELS 32
 #define MIN_RCIN_CHANNELS  5
 
 class AP_RCProtocol_Backend;
@@ -29,10 +29,13 @@ public:
         SBUS,
         SBUS_NI,
         DSM,
+        SUMD,
         NONE    //last enum always is None
     };
     void init();
+    bool valid_serial_prot() { return _valid_serial_prot; }
     void process_pulse(uint32_t width_s0, uint32_t width_s1);
+    void process_byte(uint8_t byte);
     enum rcprotocol_t protocol_detected() { return _detected_protocol; }
     uint8_t num_channels();
     uint16_t read(uint8_t chan);
@@ -44,6 +47,7 @@ private:
     AP_RCProtocol_Backend *backend[NONE];
     bool _new_input = false;
     uint32_t _last_input_ms;
+    bool _valid_serial_prot = false;
 };
 
 #include "AP_RCProtocol_Backend.h"

libraries/AP_RCProtocol/AP_RCProtocol_Backend.h

@@ -25,7 +25,8 @@ class AP_RCProtocol_Backend
 
 public:
     AP_RCProtocol_Backend(AP_RCProtocol &_frontend);
-    virtual void process_pulse(uint32_t width_s0, uint32_t width_s1) = 0;
+    virtual void process_pulse(uint32_t width_s0, uint32_t width_s1) {}
+    virtual void process_byte(uint8_t byte) {}
     uint16_t read(uint8_t chan);
     bool new_input();
     uint8_t num_channels();
@@ -35,7 +36,10 @@ public:
 
     // allow for backends that need regular polling
     virtual void update(void) {}
-
+    enum {
+        PARSE_TYPE_SIGREAD,
+        PARSE_TYPE_SERIAL
+    };
 protected:
     void add_input(uint8_t num_channels, uint16_t *values, bool in_failsafe);
     

libraries/AP_RCProtocol/AP_RCProtocol_SUMD.cpp

@@ -0,0 +1,384 @@
+/*
+  SUMD decoder, based on PX4Firmware/src/rc/lib/rc/sumd.c from PX4Firmware
+  modified for use in AP_HAL_* by Andrew Tridgell
+ */
+/****************************************************************************
+ *
+ *   Copyright (c) 2015 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 sumd.h
+ *
+ * RC protocol definition for Graupner HoTT transmitter (SUMD/SUMH Protocol)
+ *
+ * @author Marco Bauer <marco@wtns.de>
+ */
+#include "AP_RCProtocol_SUMD.h"
+
+#define SUMD_HEADER_LENGTH	3
+#define SUMD_HEADER_ID		0xA8
+#define SUMD_ID_SUMH		0x00
+#define SUMD_ID_SUMD		0x01
+#define SUMD_ID_FAILSAFE	0x81
+
+/* define range mapping here, -+100% -> 1000..2000 */
+#define SUMD_RANGE_MIN 0.0f
+#define SUMD_RANGE_MAX 4096.0f
+
+#define SUMD_TARGET_MIN 1000.0f
+#define SUMD_TARGET_MAX 2000.0f
+
+/* pre-calculate the floating point stuff as far as possible at compile time */
+#define SUMD_SCALE_FACTOR ((SUMD_TARGET_MAX - SUMD_TARGET_MIN) / (SUMD_RANGE_MAX - SUMD_RANGE_MIN))
+#define SUMD_SCALE_OFFSET (int)(SUMD_TARGET_MIN - (SUMD_SCALE_FACTOR * SUMD_RANGE_MIN + 0.5f))
+
+// #define SUMD_DEBUG
+extern const AP_HAL::HAL& hal;
+
+uint16_t AP_RCProtocol_SUMD::sumd_crc16(uint16_t crc, uint8_t value)
+{
+	int i;
+	crc ^= (uint16_t)value << 8;
+
+	for (i = 0; i < 8; i++) {
+		crc = (crc & 0x8000) ? (crc << 1) ^ 0x1021 : (crc << 1);
+	}
+
+	return crc;
+}
+
+uint8_t AP_RCProtocol_SUMD::sumd_crc8(uint8_t crc, uint8_t value)
+{
+	crc += value;
+	return crc;
+}
+
+void AP_RCProtocol_SUMD::process_pulse(uint32_t width_s0, uint32_t width_s1)
+{
+    // convert to bit widths, allowing for up to about 4usec error, assuming 115200 bps
+    uint16_t bits_s0 = ((width_s0+4)*(uint32_t)115200) / 1000000;
+    uint16_t bits_s1 = ((width_s1+4)*(uint32_t)115200) / 1000000;
+    uint8_t bit_ofs, byte_ofs;
+    uint16_t nbits;
+
+    if (bits_s0 == 0 || bits_s1 == 0) {
+        // invalid data
+        goto reset;
+    }
+
+    byte_ofs = sumd_state.bit_ofs/10;
+    bit_ofs = sumd_state.bit_ofs%10;
+
+    // pull in the high bits
+    nbits = bits_s0;
+    if (nbits+bit_ofs > 10) {
+        nbits = 10 - bit_ofs;
+    }
+    sumd_state.bytes[byte_ofs] |= ((1U<<nbits)-1) << bit_ofs;
+    sumd_state.bit_ofs += nbits;
+    bit_ofs += nbits;
+    if (bits_s0 - nbits > 10) {
+        // we have a full frame
+        uint8_t byte;
+        uint8_t i;
+        for (i=0; i <= byte_ofs; i++) {
+            // get raw data
+            uint16_t v = sumd_state.bytes[i];
+
+            // check start bit
+            if ((v & 1) != 0) {
+                break;
+            }
+            // check stop bits
+            if ((v & 0x200) != 0x200) {
+                break;
+            }
+            byte = ((v>>1) & 0xFF);
+            process_byte(byte);
+        }
+        memset(&sumd_state, 0, sizeof(sumd_state));
+    }
+
+    byte_ofs = sumd_state.bit_ofs/10;
+    bit_ofs = sumd_state.bit_ofs%10;
+
+    if (bits_s1+bit_ofs > 10) {
+        // invalid data
+        goto reset;
+    }
+
+    // pull in the low bits
+    sumd_state.bit_ofs += bits_s1;
+    return;
+reset:
+    memset(&sumd_state, 0, sizeof(sumd_state));
+}
+
+void AP_RCProtocol_SUMD::process_byte(uint8_t byte)
+{
+	switch (_decode_state) {
+	case SUMD_DECODE_STATE_UNSYNCED:
+#ifdef SUMD_DEBUG
+        hal.console->printf(" SUMD_DECODE_STATE_UNSYNCED \n") ;
+#endif
+		if (byte == SUMD_HEADER_ID) {
+			_rxpacket.header = byte;
+			_sumd = true;
+			_rxlen = 0;
+			_crc16 = 0x0000;
+			_crc8 = 0x00;
+			_crcOK = false;
+			_crc16 = sumd_crc16(_crc16, byte);
+			_crc8 = sumd_crc8(_crc8, byte);
+			_decode_state = SUMD_DECODE_STATE_GOT_HEADER;
+
+#ifdef SUMD_DEBUG
+        hal.console->printf(" SUMD_DECODE_STATE_GOT_HEADER: %x \n", byte) ;
+#endif
+		}
+		break;
+
+	case SUMD_DECODE_STATE_GOT_HEADER:
+		if (byte == SUMD_ID_SUMD || byte == SUMD_ID_SUMH) {
+			_rxpacket.status = byte;
+
+			if (byte == SUMD_ID_SUMH) {
+				_sumd = false;
+			}
+
+			if (_sumd) {
+				_crc16 = sumd_crc16(_crc16, byte);
+
+			} else {
+				_crc8 = sumd_crc8(_crc8, byte);
+			}
+
+			_decode_state = SUMD_DECODE_STATE_GOT_STATE;
+
+#ifdef SUMD_DEBUG
+            hal.console->printf(" SUMD_DECODE_STATE_GOT_STATE: %x \n", byte) ;
+#endif
+
+		} else {
+			_decode_state = SUMD_DECODE_STATE_UNSYNCED;
+		}
+
+		break;
+
+	case SUMD_DECODE_STATE_GOT_STATE:
+		if (byte >= 2 && byte <= SUMD_MAX_CHANNELS) {
+			_rxpacket.length = byte;
+
+			if (_sumd) {
+				_crc16 = sumd_crc16(_crc16, byte);
+
+			} else {
+				_crc8 = sumd_crc8(_crc8, byte);
+			}
+
+			_rxlen++;
+			_decode_state = SUMD_DECODE_STATE_GOT_LEN;
+
+#ifdef SUMD_DEBUG
+            hal.console->printf(" SUMD_DECODE_STATE_GOT_LEN: %x (%d) \n", byte, byte) ;
+#endif
+
+		} else {
+			_decode_state = SUMD_DECODE_STATE_UNSYNCED;
+		}
+
+		break;
+
+	case SUMD_DECODE_STATE_GOT_LEN:
+		_rxpacket.sumd_data[_rxlen] = byte;
+
+		if (_sumd) {
+			_crc16 = sumd_crc16(_crc16, byte);
+
+		} else {
+			_crc8 = sumd_crc8(_crc8, byte);
+		}
+
+		_rxlen++;
+
+		if (_rxlen <= ((_rxpacket.length * 2))) {
+#ifdef SUMD_DEBUG
+            hal.console->printf(" SUMD_DECODE_STATE_GOT_DATA[%d]: %x\n", _rxlen - 2, byte) ;
+#endif
+
+		} else {
+			_decode_state = SUMD_DECODE_STATE_GOT_DATA;
+
+#ifdef SUMD_DEBUG
+            hal.console->printf(" SUMD_DECODE_STATE_GOT_DATA -- finish --\n") ;
+#endif
+
+		}
+
+		break;
+
+	case SUMD_DECODE_STATE_GOT_DATA:
+		_rxpacket.crc16_high = byte;
+
+#ifdef SUMD_DEBUG
+        hal.console->printf(" SUMD_DECODE_STATE_GOT_CRC16[1]: %x   [%x]\n", byte, ((_crc16 >> 8) & 0xff)) ;
+#endif
+
+		if (_sumd) {
+			_decode_state = SUMD_DECODE_STATE_GOT_CRC;
+
+		} else {
+			_decode_state = SUMD_DECODE_STATE_GOT_CRC16_BYTE_1;
+		}
+
+		break;
+
+	case SUMD_DECODE_STATE_GOT_CRC16_BYTE_1:
+		_rxpacket.crc16_low = byte;
+
+#ifdef SUMD_DEBUG
+        hal.console->printf(" SUMD_DECODE_STATE_GOT_CRC16[2]: %x   [%x]\n", byte, (_crc16 & 0xff)) ;
+#endif
+
+		_decode_state = SUMD_DECODE_STATE_GOT_CRC16_BYTE_2;
+
+		break;
+
+	case SUMD_DECODE_STATE_GOT_CRC16_BYTE_2:
+		_rxpacket.telemetry = byte;
+
+#ifdef SUMD_DEBUG
+        hal.console->printf(" SUMD_DECODE_STATE_GOT_SUMH_TELEMETRY: %x\n", byte) ;
+#endif
+
+		_decode_state = SUMD_DECODE_STATE_GOT_CRC;
+
+		break;
+
+	case SUMD_DECODE_STATE_GOT_CRC:
+		if (_sumd) {
+			_rxpacket.crc16_low = byte;
+
+#ifdef SUMD_DEBUG
+            hal.console->printf(" SUMD_DECODE_STATE_GOT_CRC[2]: %x   [%x]\n\n", byte, (_crc16 & 0xff)) ;
+#endif
+
+			if (_crc16 == (uint16_t)(_rxpacket.crc16_high << 8) + _rxpacket.crc16_low) {
+				_crcOK = true;
+			}
+
+		} else {
+			_rxpacket.crc8 = byte;
+
+#ifdef SUMD_DEBUG
+            hal.console->printf(" SUMD_DECODE_STATE_GOT_CRC8_SUMH: %x   [%x]\n\n", byte, _crc8) ;
+#endif
+
+			if (_crc8 == _rxpacket.crc8) {
+				_crcOK = true;
+			}
+		}
+
+		if (_crcOK) {
+#ifdef SUMD_DEBUG
+            hal.console->printf(" CRC - OK \n") ;
+#endif
+            if (_sumd) {
+#ifdef SUMD_DEBUG
+                hal.console->printf(" Got valid SUMD Packet\n") ;
+#endif
+			} else {
+#ifdef SUMD_DEBUG
+                hal.console->printf(" Got valid SUMH Packet\n") ;
+#endif
+
+			}
+
+#ifdef SUMD_DEBUG
+				hal.console->printf(" RXLEN: %d  [Chans: %d] \n\n", _rxlen - 1, (_rxlen - 1) / 2) ;
+#endif
+
+
+			unsigned i;
+            uint8_t num_values;
+            uint16_t values[SUMD_MAX_CHANNELS];
+
+			/* received Channels */
+			if ((uint16_t)_rxpacket.length > SUMD_MAX_CHANNELS) {
+				_rxpacket.length = (uint8_t) SUMD_MAX_CHANNELS;
+			}
+
+			num_values = (uint16_t)_rxpacket.length;
+
+			/* decode the actual packet */
+			/* reorder first 4 channels */
+
+			/* ch1 = roll -> sumd = ch2 */
+			values[0] = (uint16_t)((_rxpacket.sumd_data[1 * 2 + 1] << 8) | _rxpacket.sumd_data[1 * 2 + 2]) >> 3;
+			/* ch2 = pitch -> sumd = ch2 */
+			values[1] = (uint16_t)((_rxpacket.sumd_data[2 * 2 + 1] << 8) | _rxpacket.sumd_data[2 * 2 + 2]) >> 3;
+			/* ch3 = throttle -> sumd = ch2 */
+			values[2] = (uint16_t)((_rxpacket.sumd_data[0 * 2 + 1] << 8) | _rxpacket.sumd_data[0 * 2 + 2]) >> 3;
+			/* ch4 = yaw -> sumd = ch2 */
+			values[3] = (uint16_t)((_rxpacket.sumd_data[3 * 2 + 1] << 8) | _rxpacket.sumd_data[3 * 2 + 2]) >> 3;
+
+			/* we start at channel 5(index 4) */
+			unsigned chan_index = 4;
+
+			for (i = 4; i < _rxpacket.length; i++) {
+#ifdef SUMD_DEBUG
+                hal.console->printf("ch[%d] : %x %x [ %x    %d ]\n", i + 1, _rxpacket.sumd_data[i * 2 + 1], _rxpacket.sumd_data[i * 2 + 2],
+					       ((_rxpacket.sumd_data[i * 2 + 1] << 8) | _rxpacket.sumd_data[i * 2 + 2]) >> 3,
+					       ((_rxpacket.sumd_data[i * 2 + 1] << 8) | _rxpacket.sumd_data[i * 2 + 2]) >> 3);
+#endif
+
+				values[chan_index] = (uint16_t)((_rxpacket.sumd_data[i * 2 + 1] << 8) | _rxpacket.sumd_data[i * 2 + 2]) >> 3;
+				/* convert values to 1000-2000 ppm encoding in a not too sloppy fashion */
+				//channels[chan_index] = (uint16_t)(channels[chan_index] * SUMD_SCALE_FACTOR + .5f) + SUMD_SCALE_OFFSET;
+
+				chan_index++;
+			}
+            if (_rxpacket.status == 0x01) {
+                add_input(num_values, values, false);
+            } else if (_rxpacket.status == 0x81) {
+                add_input(num_values, values, true);                
+            }
+		} else {
+#ifdef SUMD_DEBUG
+            hal.console->printf(" CRC - fail 0x%X 0x%X\n", _crc16, (uint16_t)(_rxpacket.crc16_high << 8) + _rxpacket.crc16_low);
+#endif
+		}
+
+		_decode_state = SUMD_DECODE_STATE_UNSYNCED;
+		break;
+	}
+}

libraries/AP_RCProtocol/AP_RCProtocol_SUMD.h

@@ -0,0 +1,69 @@
+/*
+ * This file is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ * 
+ * Code by Andrew Tridgell and Siddharth Bharat Purohit
+ */
+
+#pragma once
+
+#include "AP_RCProtocol.h"
+#define SUMD_MAX_CHANNELS	32
+
+class AP_RCProtocol_SUMD : public AP_RCProtocol_Backend {
+public:
+    AP_RCProtocol_SUMD(AP_RCProtocol &_frontend) : AP_RCProtocol_Backend(_frontend) {}
+    void process_pulse(uint32_t width_s0, uint32_t width_s1) override;
+    void process_byte(uint8_t byte) override;
+private:
+    static uint16_t sumd_crc16(uint16_t crc, uint8_t value);
+    static uint8_t sumd_crc8(uint8_t crc, uint8_t value);
+
+    #pragma pack(push, 1)
+    typedef struct {
+        uint8_t	header;							///< 0xA8 for a valid packet
+        uint8_t	status;							///< 0x01 valid and live SUMD data frame / 0x00 = SUMH / 0x81 = Failsafe
+        uint8_t	length;							///< Channels
+        uint8_t	sumd_data[SUMD_MAX_CHANNELS * 2];	///< ChannelData (High Byte/ Low Byte)
+        uint8_t	crc16_high;						///< High Byte of 16 Bit CRC
+        uint8_t	crc16_low;						///< Low Byte of 16 Bit CRC
+        uint8_t	telemetry;						///< Telemetry request
+        uint8_t	crc8;							///< SUMH CRC8
+    } ReceiverFcPacketHoTT;
+    #pragma pack(pop)
+
+
+    enum SUMD_DECODE_STATE {
+        SUMD_DECODE_STATE_UNSYNCED = 0,
+        SUMD_DECODE_STATE_GOT_HEADER,
+        SUMD_DECODE_STATE_GOT_STATE,
+        SUMD_DECODE_STATE_GOT_LEN,
+        SUMD_DECODE_STATE_GOT_DATA,
+        SUMD_DECODE_STATE_GOT_CRC,
+        SUMD_DECODE_STATE_GOT_CRC16_BYTE_1,
+        SUMD_DECODE_STATE_GOT_CRC16_BYTE_2
+    };
+
+    enum SUMD_DECODE_STATE _decode_state = SUMD_DECODE_STATE_UNSYNCED;
+    uint8_t _rxlen;
+    ReceiverFcPacketHoTT _rxpacket;
+    uint8_t 	_crc8 	= 0x00;
+    uint16_t 	_crc16  = 0x0000;
+    bool 		_sumd	= true;
+    bool		_crcOK	= false;
+    struct {
+        uint16_t bytes[40];
+        uint8_t bit_ofs;
+        bool packet_parsed;
+    } sumd_state;
+};

libraries/AP_RCProtocol/AP_RCProtocol_SUMD_NI.h

@@ -0,0 +1,31 @@
+/*
+ * This file is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ * 
+ */
+
+#pragma once
+
+#include "AP_RCProtocol.h"
+#include "AP_RCProtocol_SUMD.h"
+
+class AP_RCProtocol_SUMD_NI : public AP_RCProtocol_SUMD {
+public:
+    AP_RCProtocol_SUMD_NI(AP_RCProtocol &_frontend) : AP_RCProtocol_SUMD(_frontend), saved_width(0) {}
+    void process_pulse(uint32_t width_s0, uint32_t width_s1) override {
+        AP_RCProtocol_SUMD::process_pulse(saved_width, width_s0);
+        saved_width = width_s1;
+    }
+private:
+    uint32_t saved_width;
+};