Additional crc functions

make/source.mk

@@ -5,6 +5,7 @@ COMMON_SRC = \
             $(TARGET_DIR_SRC) \
             main.c \
             common/bitarray.c \
+            common/crc.c \
             common/encoding.c \
             common/filter.c \
             common/huffman.c \

src/main/common/crc.c

@@ -0,0 +1,79 @@
+/*
+ * This file is part of Cleanflight.
+ *
+ * Cleanflight 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.
+ *
+ * Cleanflight 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 Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdint.h>
+
+#include "streambuf.h"
+
+
+uint16_t crc16_ccitt(uint16_t crc, unsigned char a)
+{
+    crc ^= (uint16_t)a << 8;
+    for (int ii = 0; ii < 8; ++ii) {
+        if (crc & 0x8000) {
+            crc = (crc << 1) ^ 0x1021;
+        } else {
+            crc = crc << 1;
+        }
+    }
+    return crc;
+}
+
+uint16_t crc16_ccitt_update(uint16_t crc, const void *data, uint32_t length)
+{
+    const uint8_t *p = (const uint8_t *)data;
+    const uint8_t *pend = p + length;
+
+    for (; p != pend; p++) {
+        crc = crc16_ccitt(crc, *p);
+    }
+    return crc;
+}
+
+uint8_t crc8_dvb_s2(uint8_t crc, unsigned char a)
+{
+    crc ^= a;
+    for (int ii = 0; ii < 8; ++ii) {
+        if (crc & 0x80) {
+            crc = (crc << 1) ^ 0xD5;
+        } else {
+            crc = crc << 1;
+        }
+    }
+    return crc;
+}
+
+uint8_t crc8_dvb_s2_update(uint8_t crc, const void *data, uint32_t length)
+{
+    const uint8_t *p = (const uint8_t *)data;
+    const uint8_t *pend = p + length;
+
+    for (; p != pend; p++) {
+        crc = crc8_dvb_s2(crc, *p);
+    }
+    return crc;
+}
+
+void crc8_dvb_s2_sbuf_append(sbuf_t *dst, uint8_t *start)
+{
+    uint8_t crc = 0;
+    const uint8_t *end = dst->ptr;
+    for (uint8_t *ptr = start; ptr < end; ++ptr) {
+        crc = crc8_dvb_s2(crc, *ptr);
+    }
+    sbufWriteU8(dst, crc);
+}

src/main/common/crc.h

@@ -0,0 +1,25 @@
+/*
+ * This file is part of Cleanflight.
+ *
+ * Cleanflight 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.
+ *
+ * Cleanflight 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 Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+uint16_t crc16_ccitt(uint16_t crc, unsigned char a);
+uint16_t crc16_ccitt_update(uint16_t crc, const void *data, uint32_t length);
+uint8_t crc8_dvb_s2(uint8_t crc, unsigned char a);
+uint8_t crc8_dvb_s2_update(uint8_t crc, const void *data, uint32_t length);
+struct sbuf_s;
+void crc8_dvb_s2_sbuf_append(struct sbuf_s *dst, uint8_t *start);

src/main/common/maths.c

@@ -345,41 +345,3 @@ int16_t qMultiply(fix12_t q, int16_t input) {
 fix12_t  qConstruct(int16_t num, int16_t den) {
     return (num << 12) / den;
 }
-
-uint16_t crc16_ccitt(uint16_t crc, unsigned char a)
-{
-    crc ^= (uint16_t)a << 8;
-    for (int ii = 0; ii < 8; ++ii) {
-        if (crc & 0x8000) {
-            crc = (crc << 1) ^ 0x1021;
-        } else {
-            crc = crc << 1;
-        }
-    }
-    return crc;
-}
-
-uint16_t crc16_ccitt_update(uint16_t crc, const void *data, uint32_t length)
-{
-    const uint8_t *p = (const uint8_t *)data;
-    const uint8_t *pend = p + length;
-
-    for (; p != pend; p++) {
-        crc = crc16_ccitt(crc, *p);
-    }
-    return crc;
-}
-
-uint8_t crc8_dvb_s2(uint8_t crc, unsigned char a)
-{
-    crc ^= a;
-    for (int ii = 0; ii < 8; ++ii) {
-        if (crc & 0x80) {
-            crc = (crc << 1) ^ 0xD5;
-        } else {
-            crc = crc << 1;
-        }
-    }
-    return crc;
-}
-

src/main/common/maths.h

@@ -142,6 +142,3 @@ static inline float constrainf(float amt, float low, float high)
     else
         return amt;
 }
-uint16_t crc16_ccitt(uint16_t crc, unsigned char a);
-uint16_t crc16_ccitt_update(uint16_t crc, const void *data, uint32_t length);
-uint8_t crc8_dvb_s2(uint8_t crc, unsigned char a);

src/main/config/config_eeprom.c

@@ -23,7 +23,7 @@
 
 #include "build/build_config.h"
 
-#include "common/maths.h"
+#include "common/crc.h"
 #include "common/utils.h"
 
 #include "config/config_eeprom.h"

src/main/drivers/rx_xn297.c

@@ -23,7 +23,7 @@
 
 #include "rx_spi.h"
 #include "rx_nrf24l01.h"
-#include "common/maths.h"
+#include "common/crc.h"
 
 
 static const uint8_t xn297_data_scramble[30] = {

src/main/rx/crsf.c

@@ -27,6 +27,7 @@
 #include "build/build_config.h"
 #include "build/debug.h"
 
+#include "common/crc.h"
 #include "common/maths.h"
 #include "common/utils.h"
 

src/main/telemetry/crsf.c

@@ -29,6 +29,7 @@
 #include "config/parameter_group.h"
 #include "config/parameter_group_ids.h"
 
+#include "common/crc.h"
 #include "common/maths.h"
 #include "common/streambuf.h"
 #include "common/utils.h"

src/test/Makefile

@@ -163,7 +163,8 @@ rc_controls_unittest_SRC := \
 
 rx_crsf_unittest_SRC := \
 		$(USER_DIR)/rx/crsf.c \
-		$(USER_DIR)/common/maths.c
+		$(USER_DIR)/common/crc.c \
+		$(USER_DIR)/common/streambuf.c
 
 
 rx_ibus_unittest_SRC := \
@@ -186,12 +187,15 @@ rx_rx_unittest_SRC := \
 
 
 scheduler_unittest_SRC := \
-		$(USER_DIR)/scheduler/scheduler.c
+		$(USER_DIR)/scheduler/scheduler.c \
+		$(USER_DIR)/common/crc.c \
+		$(USER_DIR)/common/streambuf.c
 
 
 telemetry_crsf_unittest_SRC := \
 		$(USER_DIR)/rx/crsf.c \
 		$(USER_DIR)/telemetry/crsf.c \
+		$(USER_DIR)/common/crc.c \
 		$(USER_DIR)/common/maths.c \
 		$(USER_DIR)/common/streambuf.c \
 		$(USER_DIR)/common/gps_conversion.c \

src/test/unit/rx_crsf_unittest.cc

@@ -26,7 +26,7 @@ extern "C" {
 
     #include "build/debug.h"
 
-    #include "common/maths.h"
+    #include "common/crc.h"
     #include "common/utils.h"
 
     #include "io/serial.h"

src/test/unit/telemetry_crsf_unittest.cc

@@ -27,6 +27,7 @@ extern "C" {
     #include "build/debug.h"
 
     #include "common/axis.h"
+    #include "common/crc.h"
     #include "common/filter.h"
     #include "common/gps_conversion.h"
     #include "common/maths.h"