From 6174c80662558586e352f0ddd0b82fdfdc443327 Mon Sep 17 00:00:00 2001 From: lixianjing Date: Mon, 2 Oct 2023 07:17:29 +0800 Subject: [PATCH] add tkc_crc16_modbus --- docs/changes.md | 3 +++ src/tkc/crc.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++ src/tkc/crc.h | 13 +++++++++++ tests/crc_test.cc | 5 +++++ 4 files changed, 78 insertions(+) diff --git a/docs/changes.md b/docs/changes.md index 77b11d53a..38c314301 100644 --- a/docs/changes.md +++ b/docs/changes.md @@ -1,5 +1,8 @@ # 最新动态 +2023/10/02 + * 增加函数tkc\_crc16\_modbus。 + 2023/10/01 * 增加函数url\_get\_param\_int32/url\_get\_param\_bool diff --git a/src/tkc/crc.c b/src/tkc/crc.c index 40d1a5700..73d9e32e8 100644 --- a/src/tkc/crc.c +++ b/src/tkc/crc.c @@ -67,6 +67,63 @@ uint16_t tk_crc16(uint16_t crc, const uint8_t* data, int data_length) { return crc ^ ~0U; } +/*https://modbus.org/docs/Modbus_over_serial_line_V1_01.pdf*/ +/*https://en.wikipedia.org/wiki/Modbus#Modbus_RTU_frame_format*/ +/*Polynomial: x16 + x15 + x2 + 1 (CRC-16-MODBUS, normal hexadecimal algebraic polynomial being 8005 and reversed A001).*/ +/*Initial value: 65,535.*/ + +static const uint8_t table_crc_hi[] = { + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, + 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, + 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, + 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, + 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, + 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40}; + +/* Table of CRC values for low-order byte */ +static const uint8_t table_crc_lo[] = { + 0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2, 0xC6, 0x06, 0x07, 0xC7, 0x05, 0xC5, 0xC4, 0x04, + 0xCC, 0x0C, 0x0D, 0xCD, 0x0F, 0xCF, 0xCE, 0x0E, 0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09, 0x08, 0xC8, + 0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A, 0x1E, 0xDE, 0xDF, 0x1F, 0xDD, 0x1D, 0x1C, 0xDC, + 0x14, 0xD4, 0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6, 0xD2, 0x12, 0x13, 0xD3, 0x11, 0xD1, 0xD0, 0x10, + 0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3, 0xF2, 0x32, 0x36, 0xF6, 0xF7, 0x37, 0xF5, 0x35, 0x34, 0xF4, + 0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E, 0xFE, 0xFA, 0x3A, 0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38, + 0x28, 0xE8, 0xE9, 0x29, 0xEB, 0x2B, 0x2A, 0xEA, 0xEE, 0x2E, 0x2F, 0xEF, 0x2D, 0xED, 0xEC, 0x2C, + 0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26, 0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0, + 0xA0, 0x60, 0x61, 0xA1, 0x63, 0xA3, 0xA2, 0x62, 0x66, 0xA6, 0xA7, 0x67, 0xA5, 0x65, 0x64, 0xA4, + 0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F, 0x6E, 0xAE, 0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68, + 0x78, 0xB8, 0xB9, 0x79, 0xBB, 0x7B, 0x7A, 0xBA, 0xBE, 0x7E, 0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C, + 0xB4, 0x74, 0x75, 0xB5, 0x77, 0xB7, 0xB6, 0x76, 0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71, 0x70, 0xB0, + 0x50, 0x90, 0x91, 0x51, 0x93, 0x53, 0x52, 0x92, 0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94, 0x54, + 0x9C, 0x5C, 0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E, 0x5A, 0x9A, 0x9B, 0x5B, 0x99, 0x59, 0x58, 0x98, + 0x88, 0x48, 0x49, 0x89, 0x4B, 0x8B, 0x8A, 0x4A, 0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C, + 0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86, 0x82, 0x42, 0x43, 0x83, 0x41, 0x81, 0x80, 0x40}; + +uint16_t tkc_crc16_modbus(const uint8_t* data, uint32_t len) { + unsigned int i = 0; + uint8_t crc_hi = 0xFF; + uint8_t crc_lo = 0xFF; + + while (len--) { + i = crc_lo ^ *data++; + crc_lo = crc_hi ^ table_crc_hi[i]; + crc_hi = table_crc_lo[i]; + } + + return (crc_hi << 8 | crc_lo); +} + + #endif #ifdef CONFIG_ENABLE_CHECKSUM diff --git a/src/tkc/crc.h b/src/tkc/crc.h index af066959a..fe4a4e482 100644 --- a/src/tkc/crc.h +++ b/src/tkc/crc.h @@ -86,6 +86,19 @@ uint16_t tk_crc16(uint16_t crc, const uint8_t* data, int size); * @return {uint16_t} 返回计算结果。 */ uint16_t tk_crc16_byte(uint16_t crc, uint8_t data); + +/** + * @method tk_crc16_modbus + * 计算crc16(MODBUS)。 + * @annotation ["static"] + * @param {uint16_t} crc 初始值(一般用PPPINITFCS16) + * @param {const uint8_t*} data 数据。 + * @param {int} size 数据长度。 + * + * @return {uint16_t} 返回计算结果。 + */ +uint16_t tkc_crc16_modbus(const uint8_t* data, uint32_t len); + #endif #ifdef CONFIG_ENABLE_FCS32 diff --git a/tests/crc_test.cc b/tests/crc_test.cc index 3cd188743..18a7fd20d 100644 --- a/tests/crc_test.cc +++ b/tests/crc_test.cc @@ -4,3 +4,8 @@ TEST(crc, crc32_file) { ASSERT_EQ(tk_crc32_file("tests/testdata/test.png", 1024), 1567897941); } + +TEST(crc, crc32_modbus) { + uint8_t data[] = {0x11, 0x05, 0x01, 0x30, 0xff, 0x00}; + ASSERT_EQ(tkc_crc16_modbus(data, sizeof(data)), 0x598f); +}