added mdc1200 packet encoder

Makefile

@@ -31,6 +31,7 @@ ENABLE_REDUCE_LOW_MID_TX_POWER   := 1
 # Tx Alarm 0.6 kB
 ENABLE_ALARM                     := 0
 ENABLE_TX1750                    := 0
+ENABLE_MDC1200                   := 1
 ENABLE_PWRON_PASSWORD            := 0
 ENABLE_RESET_AES_KEY             := 1
 ENABLE_BIG_FREQ                  := 0
@@ -180,6 +181,9 @@ OBJS += frequencies.o
 OBJS += functions.o
 OBJS += helper/battery.o
 OBJS += helper/boot.o
+ifeq ($(ENABLE_MDC1200),1)
+	OBJS += mdc1200.o
+endif
 OBJS += misc.o
 OBJS += radio.o
 OBJS += scheduler.o
@@ -317,6 +321,9 @@ endif
 ifeq ($(ENABLE_TX1750),1)
 	CFLAGS  += -DENABLE_TX1750
 endif
+ifeq ($(ENABLE_MDC1200),1)
+	CFLAGS  += -DENABLE_MDC1200
+endif
 ifeq ($(ENABLE_PWRON_PASSWORD),1)
 	CFLAGS  += -DENABLE_PWRON_PASSWORD
 endif

driver/bk4819.c

@@ -14,7 +14,7 @@
  *     limitations under the License.
  */
 
-#include <stdio.h>   // NULL
+#include <string.h>   // NULL and memset
 
 #include "bk4819.h"
 #include "bsp/dp32g030/gpio.h"
@@ -23,6 +23,9 @@
 #include "driver/system.h"
 #include "driver/systick.h"
 #include "misc.h"
+#ifdef ENABLE_MDC1200
+	#include "mdc1200.h"
+#endif
 
 #ifndef ARRAY_SIZE
 	#define ARRAY_SIZE(x) (sizeof(x) / sizeof(x[0]))
@@ -1924,13 +1927,27 @@ void BK4819_start_fsk_rx(const unsigned int packet_size)
 
 void BK4819_PlayRogerMDC1200(void)
 {
-	static const uint8_t MDC1200_DATA[] = {
+	uint16_t fsk_reg59;
+
+	#ifdef ENABLE_MDC1200
+		const uint8_t  op  = 0x12;
+		const uint8_t  arg = 0x34;
+		const uint16_t id  = 0x5678;
+
+		uint8_t packet[8 + 40];
+		memset(packet + 0, 0x00, 4);
+		memset(packet + 4, 0xff, 4);
+		const unsigned int size = MDC1200_encode_single_packet(packet + 8, op, arg, id);
+
+	#else
+		static const uint8_t packet[] = {
 			0x00, 0x00, 0x00, 0x00,
 			0xff, 0xff, 0xff, 0xff,
 			// this needs properly computing for MDC1200
 			0xA2, 0xF1, 0x46, 0x74, 0xA4, 0x61, 0x44, 0x65, 0x8A, 0x4E, 0x44, 0xE0, 0x84, 0xEA
+		const unsigned int size = sizeof(packet);
 	};
-	uint16_t fsk_reg59;
+	#endif
 
 	BK4819_SetAF(BK4819_AF_MUTE);
 //	BK4819_SetAF(BK4819_AF_BEEP);
@@ -2020,7 +2037,7 @@ void BK4819_PlayRogerMDC1200(void)
 		(96u <<  0));
 
 	// Set FSK data length
-	BK4819_WriteRegister(BK4819_REG_5D, ((sizeof(MDC1200_DATA) - 1) << 8));
+	BK4819_WriteRegister(BK4819_REG_5D, ((size - 1) << 8));
 
 	// REG_59
 	//
@@ -2103,10 +2120,10 @@ void BK4819_PlayRogerMDC1200(void)
 	//
 	BK4819_WriteRegister(BK4819_REG_5C, 0xAA30);   // 101010100 0 110000
 
-	{	// load the packet data
+	{	// load the packet data into the TX FIFO buffer
 		unsigned int i;
-		const uint16_t *p = (const uint16_t *)MDC1200_DATA;
+		const uint16_t *p = (const uint16_t *)packet;
-		for (i = 0; i < (sizeof(MDC1200_DATA) / 2); i++)
+		for (i = 0; i < (size / 2); i++)
 			BK4819_WriteRegister(BK4819_REG_5F, p[i]);
 	}
 
@@ -2116,7 +2133,7 @@ void BK4819_PlayRogerMDC1200(void)
 	// enable TX
 	BK4819_WriteRegister(BK4819_REG_59, (1u << 11) | fsk_reg59);
 
-	{	// packet is 175ms long
+	{	// packet takes 175ms long
 		unsigned int timeout = 250 / 5;      // allow up to 250ms for the TX to complete
 		while (timeout-- > 0)
 		{

mdc1200.c

@@ -0,0 +1,150 @@
+
+#include <string.h>
+
+#include "mdc1200.h"
+
+uint16_t flip_crc(const uint16_t crc, const unsigned int bit_num)
+{
+	uint16_t i;
+	uint16_t bit;
+	uint16_t crc_out;
+	for (i = 1u << (bit_num - 1), bit = 1u, crc_out = 0u; i > 0u; i >>= 1)
+	{
+		if (crc & i)
+			 crc_out |= bit;
+		bit <<= 1;
+	}
+	return crc_out;
+}
+
+uint16_t compute_crc(const uint8_t *data, const unsigned int data_len)
+{
+	unsigned int i;
+	uint16_t crc = 0x0000;
+
+	for (i = 0; i < data_len; i++)
+	{
+		unsigned int mask;
+		const uint16_t c = flip_crc(*data++, 8);
+		for (mask = 0x80; mask > 0; mask >>= 1)
+		{
+			uint16_t bit = crc & 0x8000;
+			crc <<= 1;
+			if (c & mask)
+				bit ^= 0x8000;
+			if (bit)
+				crc ^= 0x1021;
+		}
+	}
+
+	return ~flip_crc(crc, 16);
+}
+
+uint8_t * encode_data(uint8_t *data)
+{
+	unsigned int i;
+	unsigned int k;
+	unsigned int m;
+	int      csr[7];
+	int      lbits[112];
+
+	uint16_t ccrc = compute_crc(data, 4);
+
+	data[4] = (ccrc >> 0) & 0x00ff;
+	data[5] = (ccrc >> 8) & 0x00ff;
+
+	data[6] = 0;
+
+	for (i = 0; i < 7; i++)
+		csr[i] = 0;
+
+	for (i = 0; i < 7; i++)
+	{
+		unsigned int j;
+		data[i + 7] = 0;
+		for (j = 0; j <= 7; j++)
+		{
+			unsigned int b;
+			for (k = 6; k > 0; k--)
+				csr[k] = csr[k - 1];
+			csr[0] = (data[i] >> j) & 1u;
+			b = csr[0] + csr[2] + csr[5] + csr[6];
+			data[i + 7] |= (b & 1u) << j;
+		}
+	}
+
+	k = 0;
+	m = 0;
+	for (i = 0; i < 14; i++)
+	{
+		unsigned int j;
+		for (j = 0; j <= 7; j++)
+		{
+			lbits[k] = 1u & (data[i] >> j);
+			k += 16;
+			if (k > 111)
+				k = ++m;
+		}
+	}
+
+	k = 0;
+	for (i = 0; i < 14; i++)
+	{
+		int j;
+		data[i] = 0;
+		for (j = 7; j >= 0; j--)
+			if (lbits[k++])
+				data[i] |= 1u << j;
+	}
+
+	return &data[14];
+}
+
+const uint8_t header[] = {0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x07, 0x09, 0x2a, 0x44, 0x6f};
+
+int MDC1200_encode_single_packet(uint8_t *data, const uint8_t op, const uint8_t arg, const uint16_t unit_id)
+{
+	memcpy(data, header, sizeof(header));
+	data += sizeof(header);
+
+	data[0] = op;
+	data[1] = arg;
+	data[2] = (unit_id >> 8) & 0x00ff;
+	data[3] = (unit_id >> 0) & 0x00ff;
+
+	encode_data(data);
+
+	return 26;
+}
+
+int MDC1200_encode_double_packet(uint8_t *data, const uint8_t op, const uint8_t arg, const uint16_t unit_id, const uint8_t b0, const uint8_t b1, const uint8_t b2, const uint8_t b3)
+{
+	memcpy(data, header, sizeof(header));
+	data += sizeof(header);
+
+	data[0] = op;
+	data[1] = arg;
+	data[2] = (unit_id >> 8) & 0x00ff;
+	data[3] = (unit_id >> 0) & 0x00ff;
+
+	data = encode_data(data);
+
+	data[0] = b0;
+	data[1] = b1;
+	data[2] = b2;
+	data[3] = b3;
+
+	encode_data(data);
+
+	return 40;
+}
+/*
+void test(void)
+{
+	uint8_t data[14 + 14 + 5 + 7];
+
+	const int size = MDC1200_encode_single_packet(data, 0x12, 0x34, 0x5678);
+
+//	const int size = MDC1200_encode_double_packet(data, 0x55, 0x34, 0x5678, 0x0a, 0x0b, 0x0c, 0x0d);
+}
+*/

mdc1200.h

@@ -0,0 +1,10 @@
+
+#ifndef MDC1200H
+#define MDC1200H
+
+#include <stdint.h>
+
+int MDC1200_encode_single_packet(uint8_t *data, const uint8_t op, const uint8_t arg, const uint16_t unit_id);
+int MDC1200_encode_double_packet(uint8_t *data, const uint8_t op, const uint8_t arg, const uint16_t unit_id, const uint8_t b0, const uint8_t b1, const uint8_t b2, const uint8_t b3);
+
+#endif