custom-uv-k5-firmware/driver/bk4819.c

/* Copyright 2023 Dual Tachyon
 * https://github.com/DualTachyon
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *     Unless required by applicable law or agreed to in writing, software
 *     distributed under the License is distributed on an "AS IS" BASIS,
 *     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *     See the License for the specific language governing permissions and
 *     limitations under the License.
 */

#include "bk4819.h"
#include "bsp/dp32g030/gpio.h"
#include "bsp/dp32g030/portcon.h"
#include "driver/gpio.h"
#include "driver/system.h"
#include "driver/systick.h"

static uint16_t gBK4819_GpioOutState;

bool gThisCanEnable_BK4819_Rxon;

void BK4819_Init(void)
{
	GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCN);
	GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
	GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SDA);

	BK4819_WriteRegister(BK4819_REG_00, 0x8000);
	BK4819_WriteRegister(BK4819_REG_00, 0x0000);
	BK4819_WriteRegister(BK4819_REG_37, 0x1D0F);
	BK4819_WriteRegister(BK4819_REG_36, 0x0022);
	BK4819_SetAGC(0);
	BK4819_WriteRegister(BK4819_REG_19, 0x1041);
	BK4819_WriteRegister(BK4819_REG_7D, 0xE940);
	BK4819_WriteRegister(BK4819_REG_48, 0xB3A8);
	BK4819_WriteRegister(BK4819_REG_09, 0x006F);
	BK4819_WriteRegister(BK4819_REG_09, 0x106B);
	BK4819_WriteRegister(BK4819_REG_09, 0x2067);
	BK4819_WriteRegister(BK4819_REG_09, 0x3062);
	BK4819_WriteRegister(BK4819_REG_09, 0x4050);
	BK4819_WriteRegister(BK4819_REG_09, 0x5047);
	BK4819_WriteRegister(BK4819_REG_09, 0x603A);
	BK4819_WriteRegister(BK4819_REG_09, 0x702C);
	BK4819_WriteRegister(BK4819_REG_09, 0x8041);
	BK4819_WriteRegister(BK4819_REG_09, 0x9037);
	BK4819_WriteRegister(BK4819_REG_09, 0xA025);
	BK4819_WriteRegister(BK4819_REG_09, 0xB017);
	BK4819_WriteRegister(BK4819_REG_09, 0xC0E4);
	BK4819_WriteRegister(BK4819_REG_09, 0xD0CB);
	BK4819_WriteRegister(BK4819_REG_09, 0xE0B5);
	BK4819_WriteRegister(BK4819_REG_09, 0xF09F);
	BK4819_WriteRegister(BK4819_REG_1F, 0x5454);
	BK4819_WriteRegister(BK4819_REG_3E, 0xA037);
	gBK4819_GpioOutState = 0x9000;
	BK4819_WriteRegister(BK4819_REG_33, 0x9000);
	BK4819_WriteRegister(BK4819_REG_3F, 0);
}

static uint16_t BK4819_ReadU16(void)
{
	uint8_t i;
	uint16_t Value;

	PORTCON_PORTC_IE = (PORTCON_PORTC_IE & ~PORTCON_PORTC_IE_C2_MASK) | PORTCON_PORTC_IE_C2_BITS_ENABLE;
	GPIOC->DIR = (GPIOC->DIR & ~GPIO_DIR_2_MASK) | GPIO_DIR_2_BITS_INPUT;
	SYSTICK_DelayUs(1);

	Value = 0;
	for (i = 0; i < 16; i++) {
		Value <<= 1;
		Value |= GPIO_CheckBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SDA);
		GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
		SYSTICK_DelayUs(1);
		GPIO_ClearBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
		SYSTICK_DelayUs(1);
	}
	PORTCON_PORTC_IE = (PORTCON_PORTC_IE & ~PORTCON_PORTC_IE_C2_MASK) | PORTCON_PORTC_IE_C2_BITS_DISABLE;
	GPIOC->DIR = (GPIOC->DIR & ~GPIO_DIR_2_MASK) | GPIO_DIR_2_BITS_OUTPUT;

	return Value;
}

uint16_t BK4819_GetRegister(BK4819_REGISTER_t Register)
{
	uint16_t Value;

	GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCN);
	GPIO_ClearBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
	SYSTICK_DelayUs(1);
	GPIO_ClearBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCN);

	BK4819_WriteU8(Register | 0x80);

	Value = BK4819_ReadU16();

	GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCN);
	SYSTICK_DelayUs(1);
	GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
	GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SDA);

	return Value;
}

void BK4819_WriteRegister(BK4819_REGISTER_t Register, uint16_t Data)
{
	GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCN);
	GPIO_ClearBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
	SYSTICK_DelayUs(1);
	GPIO_ClearBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCN);
	BK4819_WriteU8(Register);
	SYSTICK_DelayUs(1);
	BK4819_WriteU16(Data);
	SYSTICK_DelayUs(1);
	GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCN);
	SYSTICK_DelayUs(1);
	GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
	GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SDA);
}

void BK4819_WriteU8(uint8_t Data)
{
	uint8_t i;

	GPIO_ClearBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
	for (i = 0; i < 8; i++) {
		if ((Data & 0x80U) == 0) {
			GPIO_ClearBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SDA);
		} else {
			GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SDA);
		}
		SYSTICK_DelayUs(1);
		GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
		SYSTICK_DelayUs(1);
		Data <<= 1;
		GPIO_ClearBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
		SYSTICK_DelayUs(1);
	}
}

void BK4819_WriteU16(uint16_t Data)
{
	uint8_t i;

	GPIO_ClearBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
	for (i = 0; i < 16; i++) {
		if ((Data & 0x8000U) == 0U) {
			GPIO_ClearBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SDA);
		} else {
			GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SDA);
		}
		SYSTICK_DelayUs(1);
		GPIO_SetBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
		Data <<= 1;
		SYSTICK_DelayUs(1);
		GPIO_ClearBit(&GPIOC->DATA, GPIOC_PIN_BK4819_SCL);
		SYSTICK_DelayUs(1);
	}
}

void BK4819_SetAGC(uint8_t Value)
{
	if (Value == 0) {
		BK4819_WriteRegister(BK4819_REG_13, 0x03BE);
		BK4819_WriteRegister(BK4819_REG_12, 0x037B);
		BK4819_WriteRegister(BK4819_REG_11, 0x027B);
		BK4819_WriteRegister(BK4819_REG_10, 0x007A);
		BK4819_WriteRegister(BK4819_REG_14, 0x0019);
		BK4819_WriteRegister(BK4819_REG_49, 0x2A38);
		BK4819_WriteRegister(BK4819_REG_7B, 0x8420);
	} else if (Value == 1) {
		uint8_t i;

		BK4819_WriteRegister(BK4819_REG_13, 0x03BE);
		BK4819_WriteRegister(BK4819_REG_12, 0x037C);
		BK4819_WriteRegister(BK4819_REG_11, 0x027B);
		BK4819_WriteRegister(BK4819_REG_10, 0x007A);
		BK4819_WriteRegister(BK4819_REG_14, 0x0018);
		BK4819_WriteRegister(BK4819_REG_49, 0x2A38);
		BK4819_WriteRegister(BK4819_REG_7B, 0x318C);
		BK4819_WriteRegister(BK4819_REG_7C, 0x595E);
		BK4819_WriteRegister(BK4819_REG_20, 0x8DEF);
		for (i = 0; i < 8; i++) {
			// Bug? The bit 0x2000 below overwrites the (i << 13)
			BK4819_WriteRegister(BK4819_REG_06, ((i << 13) | 0x2500U) + 0x36U);
		}
	}
}

void BK4819_ToggleGpioOut(BK4819_GPIO_PIN_t Pin, bool bSet)
{
	if (bSet) {
		gBK4819_GpioOutState |= (0x40U >> Pin);
	} else {
		gBK4819_GpioOutState &= ~(0x40U >> Pin);
	}

	BK4819_WriteRegister(BK4819_REG_33, gBK4819_GpioOutState);
}

void BK4819_SetCDCSSCodeWord(uint32_t CodeWord)
{
	// Enable CDCSS
	// Transmit positive CDCSS code
	// CDCSS Mode
	// CDCSS 23bit
	// Enable Auto CDCSS Bw Mode
	// Enable Auto CTCSS Bw Mode
	// CTCSS/CDCSS Tx Gain1 Tuning = 51
	BK4819_WriteRegister(BK4819_REG_51, 0
			| BK4819_REG_51_ENABLE_CxCSS
			| BK4819_REG_51_GPIO6_PIN2_NORMAL
			| BK4819_REG_51_TX_CDCSS_POSITIVE
			| BK4819_REG_51_MODE_CDCSS
			| BK4819_REG_51_CDCSS_23_BIT
			| BK4819_REG_51_1050HZ_NO_DETECTION
			| BK4819_REG_51_AUTO_CDCSS_BW_ENABLE
			| BK4819_REG_51_AUTO_CTCSS_BW_ENABLE
			| (51U << BK4819_REG_51_SHIFT_CxCSS_TX_GAIN1));

	// CTC1 Frequency Control Word = 2775
	BK4819_WriteRegister(BK4819_REG_07, 0
			| BK4819_REG_07_MODE_CTC1
			| (2775U << BK4819_REG_07_SHIFT_FREQUENCY));

	// Set the code word
	BK4819_WriteRegister(BK4819_REG_08, 0x0000 | ((CodeWord >>  0) & 0xFFF));
	BK4819_WriteRegister(BK4819_REG_08, 0x8000 | ((CodeWord >> 12) & 0xFFF));
}

void BK4819_SetCTCSSBaudRate(uint32_t BaudRate)
{
	uint16_t Config;

	if (BaudRate == 2625) {
		// Enable TxCTCSS
		// CTCSS Mode
		// 1050/4 Detect Enable
		// Enable Auto CDCSS Bw Mode
		// Enable Auto CTCSS Bw Mode
		// CTCSS/CDCSS Tx Gain1 Tuning = 74
		Config = 0x944A;
	} else {
		// Enable TxCTCSS
		// CTCSS Mode
		// Enable Auto CDCSS Bw Mode
		// Enable Auto CTCSS Bw Mode
		// CTCSS/CDCSS Tx Gain1 Tuning = 74
		Config = 0x904A;
	}
	BK4819_WriteRegister(BK4819_REG_51, Config);
	// CTC1 Frequency Control Word
	BK4819_WriteRegister(BK4819_REG_07, 0
			| BK4819_REG_07_MODE_CTC1
			| ((BaudRate * 2065) / 1000) << BK4819_REG_07_SHIFT_FREQUENCY);
}

void BK4819_Set55HzTailDetection(void)
{
	// CTC2 Frequency Control Word = round_nearest(25391 / 55) = 462
	BK4819_WriteRegister(BK4819_REG_07, (1U << 13) | 462);
}

void BK4819_EnableVox(uint16_t Vox1Threshold, uint16_t Vox0Threshold)
{
	uint16_t Value;

	Value = BK4819_GetRegister(BK4819_REG_31);
	// 0xA000 is undocumented?
	BK4819_WriteRegister(BK4819_REG_46, 0xA000 | (Vox1Threshold & 0x07FF));
	// 0x1800 is undocumented?
	BK4819_WriteRegister(BK4819_REG_79, 0x1800 | (Vox0Threshold & 0x07FF));
	// Bottom 12 bits are undocumented?
	BK4819_WriteRegister(BK4819_REG_7A, 0x289A);
	// Enable VOX
	BK4819_WriteRegister(BK4819_REG_31, Value | 4);
}

void BK4819_SetFilterBandwidth(BK4819_FilterBandwidth_t Bandwidth)
{
	if (Bandwidth == BK4819_FILTER_BW_WIDE) {
		BK4819_WriteRegister(BK4819_REG_43, 0x3028);
	} else if (Bandwidth == BK4819_FILTER_BW_NARROW) {
		BK4819_WriteRegister(BK4819_REG_43, 0x4048);
	}
}

void BK4819_SetupPowerAmplifier(uint16_t Bias, uint32_t Frequency)
{
	uint8_t Gain;

	if (Bias > 255) {
		Bias = 255;
	}
	if (Frequency < 28000000) {
		// Gain 1 = 1
		// Gain 2 = 0
		Gain = 0x08U;
	} else {
		// Gain 1 = 4
		// Gain 2 = 2
		Gain = 0x22U;
	}
	// Enable PACTLoutput
	BK4819_WriteRegister(BK4819_REG_36, (Bias << 8) | 0x80U | Gain);
}

void BK4819_SetFrequency(uint32_t Frequency)
{
	BK4819_WriteRegister(BK4819_REG_38,  (Frequency >>  0) & 0xFFFF);
	BK4819_WriteRegister(BK4819_REG_39, (Frequency >> 16) & 0xFFFF);
}

void BK4819_SetupSquelch(uint8_t SquelchOpenRSSIThresh, uint8_t SquelchCloseRSSIThresh, uint8_t SquelchOpenNoiseThresh, uint8_t SquelchCloseNoiseThresh, uint8_t SquelchCloseGlitchThresh, uint8_t SquelchOpenGlitchThresh)
{
	BK4819_WriteRegister(BK4819_REG_70, 0);
	BK4819_WriteRegister(BK4819_REG_4D, 0xA000 | SquelchCloseGlitchThresh);
	// 0x6f = 0110 1111 meaning the default sql delays from the datasheet are used (101 and 111)
	BK4819_WriteRegister(BK4819_REG_4E, 0x6F00 | SquelchOpenGlitchThresh);
	BK4819_WriteRegister(BK4819_REG_4F, (SquelchCloseNoiseThresh << 8) | SquelchOpenNoiseThresh);
	BK4819_WriteRegister(BK4819_REG_78, (SquelchOpenRSSIThresh << 8) | SquelchCloseRSSIThresh);
	BK4819_SetAF(BK4819_AF_MUTE);
	BK4819_RX_TurnOn();
}

void BK4819_SetAF(BK4819_AF_Type_t AF)
{
	// AF Output Inverse Mode = Inverse
	// Undocumented bits 0x2040
	BK4819_WriteRegister(BK4819_REG_47, 0x6040 | (AF << 8));
}

void BK4819_RX_TurnOn(void)
{
	// DSP Voltage Setting = 1
	// ANA LDO = 2.7v
	// VCO LDO = 2.7v
	// RF LDO = 2.7v
	// PLL LDO = 2.7v
	// ANA LDO bypass
	// VCO LDO bypass
	// RF LDO bypass
	// PLL LDO bypass
	// Reserved bit is 1 instead of 0
	// Enable DSP
	// Enable XTAL
	// Enable Band Gap
	BK4819_WriteRegister(BK4819_REG_37, 0x1F0F);

	// Turn off everything
	BK4819_WriteRegister(BK4819_REG_30, 0);

	// Enable VCO Calibration
	// Enable RX Link
	// Enable AF DAC
	// Enable PLL/VCO
	// Disable PA Gain
	// Disable MIC ADC
	// Disable TX DSP
	// Enable RX DSP
	BK4819_WriteRegister(BK4819_REG_30, 0xBFF1);
}

void BK4819_PickRXFilterPathBasedOnFrequency(uint32_t Frequency)
{
	if (Frequency < 28000000) {
		BK4819_ToggleGpioOut(BK4819_GPIO2_PIN30, true);
		BK4819_ToggleGpioOut(BK4819_GPIO3_PIN31, false);
	} else if (Frequency == 0xFFFFFFFF) {
		BK4819_ToggleGpioOut(BK4819_GPIO2_PIN30, false);
		BK4819_ToggleGpioOut(BK4819_GPIO3_PIN31, false);
	} else {
		BK4819_ToggleGpioOut(BK4819_GPIO2_PIN30, false);
		BK4819_ToggleGpioOut(BK4819_GPIO3_PIN31, true);
	}
}

void BK4819_DisableScramble(void)
{
	uint16_t Value;

	Value = BK4819_GetRegister(BK4819_REG_31);
	BK4819_WriteRegister(BK4819_REG_31, Value & 0xFFFD);
}

void BK4819_EnableScramble(uint8_t Type)
{
	uint16_t Value;

	Value = BK4819_GetRegister(BK4819_REG_31);
	BK4819_WriteRegister(BK4819_REG_31, Value | 2);
	BK4819_WriteRegister(BK4819_REG_71, (Type * 0x0408) + 0x68DC);
}

void BK4819_DisableVox(void)
{
	uint16_t Value;

	Value = BK4819_GetRegister(BK4819_REG_31);
	BK4819_WriteRegister(BK4819_REG_31, Value & 0xFFFB);
}

void BK4819_DisableDTMF(void)
{
	BK4819_WriteRegister(BK4819_REG_24, 0);
}

void BK4819_EnableDTMF(void)
{
	BK4819_WriteRegister(BK4819_REG_21, 0x06D8);
	BK4819_WriteRegister(BK4819_REG_24, 0
		| (1U << BK4819_REG_24_SHIFT_UNKNOWN_15)
		| (24 << BK4819_REG_24_SHIFT_THRESHOLD)
		| (1U << BK4819_REG_24_SHIFT_UNKNOWN_6)
		| BK4819_REG_24_ENABLE
		| BK4819_REG_24_SELECT_DTMF
		| (14U << BK4819_REG_24_SHIFT_MAX_SYMBOLS)
		);
}

void BK4819_PlayTone(uint16_t Frequency, bool bTuningGainSwitch)
{
	uint16_t ToneConfig;

	BK4819_EnterTxMute();
	BK4819_SetAF(BK4819_AF_BEEP);

	if (bTuningGainSwitch == 0) {
		ToneConfig = 0
			| BK4819_REG_70_ENABLE_TONE1
			| (96U << BK4819_REG_70_SHIFT_TONE1_TUNING_GAIN);
	} else {
		ToneConfig = 0
			| BK4819_REG_70_ENABLE_TONE1
			| (28U << BK4819_REG_70_SHIFT_TONE1_TUNING_GAIN);
	}
	BK4819_WriteRegister(BK4819_REG_70, ToneConfig);

	BK4819_WriteRegister(BK4819_REG_30, 0);
	BK4819_WriteRegister(BK4819_REG_30, 0
			| BK4819_REG_30_ENABLE_AF_DAC
			| BK4819_REG_30_ENABLE_DISC_MODE
			| BK4819_REG_30_ENABLE_TX_DSP);
			;

	BK4819_WriteRegister(BK4819_REG_71, (uint16_t)(Frequency * 10.32444));
}

void BK4819_EnterTxMute(void)
{
	BK4819_WriteRegister(BK4819_REG_50, 0xBB20);
}

void BK4819_ExitTxMute(void)
{
	BK4819_WriteRegister(BK4819_REG_50, 0x3B20);
}

void BK4819_Sleep(void)
{
	BK4819_WriteRegister(BK4819_REG_30, 0);
	BK4819_WriteRegister(BK4819_REG_37, 0x1D00);
}

void BK4819_TurnsOffTones_TurnsOnRX(void)
{
	BK4819_WriteRegister(BK4819_REG_70, 0);
	BK4819_SetAF(BK4819_AF_MUTE);
	BK4819_ExitTxMute();
	BK4819_WriteRegister(BK4819_REG_30, 0);
	BK4819_WriteRegister(BK4819_REG_30, 0
			| BK4819_REG_30_ENABLE_VCO_CALIB
			| BK4819_REG_30_ENABLE_RX_LINK
			| BK4819_REG_30_ENABLE_AF_DAC
			| BK4819_REG_30_ENABLE_DISC_MODE
			| BK4819_REG_30_ENABLE_PLL_VCO
			| BK4819_REG_30_ENABLE_RX_DSP
			);
}

void BK4819_SetupAircopy(void)
{
	BK4819_WriteRegister(BK4819_REG_70, 0x00E0);
	BK4819_WriteRegister(BK4819_REG_72, 0x3065);
	BK4819_WriteRegister(BK4819_REG_58, 0x00C1);
	BK4819_WriteRegister(BK4819_REG_5C, 0x5665);
	BK4819_WriteRegister(BK4819_REG_5D, 0x4700);
}

void BK4819_ResetFSK(void)
{
	BK4819_WriteRegister(BK4819_REG_3F, 0x0000);
	BK4819_WriteRegister(BK4819_REG_59, 0x0068);
	SYSTEM_DelayMs(30);
	BK4819_Idle();
}

void BK4819_Idle(void)
{
	BK4819_WriteRegister(BK4819_REG_30, 0x0000);
}

void BK4819_ExitBypass(void)
{
	BK4819_SetAF(BK4819_AF_MUTE);
	BK4819_WriteRegister(BK4819_REG_7E, 0x302E);
}

void BK4819_PrepareTransmit(void)
{
	BK4819_ExitBypass();
	BK4819_ExitTxMute();
	BK4819_TxOn_Beep();
}

void BK4819_TxOn_Beep(void)
{
	BK4819_WriteRegister(BK4819_REG_37, 0x1D0F);
	BK4819_WriteRegister(BK4819_REG_52, 0x028F);
	BK4819_WriteRegister(BK4819_REG_30, 0x0000);
	BK4819_WriteRegister(BK4819_REG_30, 0xC1FE);
}

void BK4819_ExitSubAu(void)
{
	BK4819_WriteRegister(BK4819_REG_51, 0x0000);
}

void BK4819_Conditional_RX_TurnOn_and_GPIO6_Enable(void)
{
	if (gThisCanEnable_BK4819_Rxon) {
		BK4819_ToggleGpioOut(BK4819_GPIO6_PIN2, true);
		BK4819_RX_TurnOn();
	}
}

void BK4819_EnterDTMF_TX(bool bLocalLoopback)
{
	BK4819_EnableDTMF();
	BK4819_EnterTxMute();
	if (bLocalLoopback) {
		BK4819_SetAF(BK4819_AF_BEEP);
	} else {
		BK4819_SetAF(BK4819_AF_MUTE);
	}
	BK4819_WriteRegister(BK4819_REG_70, 0
		| BK4819_REG_70_MASK_ENABLE_TONE1
		| (83 << BK4819_REG_70_SHIFT_TONE1_TUNING_GAIN)
		| BK4819_REG_70_MASK_ENABLE_TONE2
		| (83 << BK4819_REG_70_SHIFT_TONE2_TUNING_GAIN)
		);

	BK4819_EnableTXLink();
}

void BK4819_ExitDTMF_TX(bool bKeep)
{
	BK4819_EnterTxMute();
	BK4819_SetAF(BK4819_AF_MUTE);
	BK4819_WriteRegister(BK4819_REG_70, 0x0000);
	BK4819_DisableDTMF();
	BK4819_WriteRegister(BK4819_REG_30, 0xC1FE);
	if (!bKeep) {
		BK4819_ExitTxMute();
	}
}

void BK4819_EnableTXLink(void)
{
	BK4819_WriteRegister(BK4819_REG_30, 0
		| BK4819_REG_30_ENABLE_VCO_CALIB
		| BK4819_REG_30_ENABLE_UNKNOWN
		| BK4819_REG_30_DISABLE_RX_LINK
		| BK4819_REG_30_ENABLE_AF_DAC
		| BK4819_REG_30_ENABLE_DISC_MODE
		| BK4819_REG_30_ENABLE_PLL_VCO
		| BK4819_REG_30_ENABLE_PA_GAIN
		| BK4819_REG_30_DISABLE_MIC_ADC
		| BK4819_REG_30_ENABLE_TX_DSP
		| BK4819_REG_30_DISABLE_RX_DSP
		);
}

void BK4819_PlayDTMF(char Code)
{
	switch (Code) {
	case '0':
		BK4819_WriteRegister(BK4819_REG_71, 0x25F3);
		BK4819_WriteRegister(BK4819_REG_72, 0x35E1);
		break;
	case '1':
		BK4819_WriteRegister(BK4819_REG_71, 0x1C1C);
		BK4819_WriteRegister(BK4819_REG_72, 0x30C2);
		break;
	case '2':
		BK4819_WriteRegister(BK4819_REG_71, 0x1C1C);
		BK4819_WriteRegister(BK4819_REG_72, 0x35E1);
		break;
	case '3':
		BK4819_WriteRegister(BK4819_REG_71, 0x1C1C);
		BK4819_WriteRegister(BK4819_REG_72, 0x3B91);
		break;
	case '4':
		BK4819_WriteRegister(BK4819_REG_71, 0x1F0E);
		BK4819_WriteRegister(BK4819_REG_72, 0x30C2);
		break;
	case '5':
		BK4819_WriteRegister(BK4819_REG_71, 0x1F0E);
		BK4819_WriteRegister(BK4819_REG_72, 0x35E1);
		break;
	case '6':
		BK4819_WriteRegister(BK4819_REG_71, 0x1F0E);
		BK4819_WriteRegister(BK4819_REG_72, 0x3B91);
		break;
	case '7':
		BK4819_WriteRegister(BK4819_REG_71, 0x225C);
		BK4819_WriteRegister(BK4819_REG_72, 0x30C2);
		break;
	case '8':
		BK4819_WriteRegister(BK4819_REG_71, 0x225c);
		BK4819_WriteRegister(BK4819_REG_72, 0x35E1);
		break;
	case '9':
		BK4819_WriteRegister(BK4819_REG_71, 0x225C);
		BK4819_WriteRegister(BK4819_REG_72, 0x3B91);
		break;
	case 'A':
		BK4819_WriteRegister(BK4819_REG_71, 0x1C1C);
		BK4819_WriteRegister(BK4819_REG_72, 0x41DC);
		break;
	case 'B':
		BK4819_WriteRegister(BK4819_REG_71, 0x1F0E);
		BK4819_WriteRegister(BK4819_REG_72, 0x41DC);
		break;
	case 'C':
		BK4819_WriteRegister(BK4819_REG_71, 0x225C);
		BK4819_WriteRegister(BK4819_REG_72, 0x41DC);
		break;
	case 'D':
		BK4819_WriteRegister(BK4819_REG_71, 0x25F3);
		BK4819_WriteRegister(BK4819_REG_72, 0x41DC);
		break;
	case '*':
		BK4819_WriteRegister(BK4819_REG_71, 0x25F3);
		BK4819_WriteRegister(BK4819_REG_72, 0x30C2);
		break;
	case '#':
		BK4819_WriteRegister(BK4819_REG_71, 0x25F3);
		BK4819_WriteRegister(BK4819_REG_72, 0x3B91);
		break;
	}
}

void BK4819_PlayDTMFString(char *pString, bool bDelayFirst, uint16_t FirstCodePersistTime, uint16_t HashCodePersistTime, uint16_t CodePersistTime, uint16_t CodeInternalTime)
{
	uint8_t i;
	uint16_t Delay;

	for (i = 0; pString[i]; i++) {
		BK4819_PlayDTMF(pString[i]);
		BK4819_ExitTxMute();
		if (bDelayFirst && i == 0) {
			Delay = FirstCodePersistTime;
		} else if (pString[i] == '*' || pString[i] == '#') {
			Delay = HashCodePersistTime;
		} else {
			Delay = CodePersistTime;
		}
		SYSTEM_DelayMs(Delay);
		BK4819_EnterTxMute();
		SYSTEM_DelayMs(CodeInternalTime);
	}
}

void BK4819_TransmitTone(bool bLocalLoopback, uint32_t Frequency)
{
	BK4819_EnterTxMute();
	BK4819_WriteRegister(BK4819_REG_70, 0
			| BK4819_REG_70_MASK_ENABLE_TONE1
			| (64U << BK4819_REG_70_SHIFT_TONE1_TUNING_GAIN));
	BK4819_WriteRegister(BK4819_REG_71, (uint16_t)(Frequency * 10.32444));
	if (bLocalLoopback) {
		BK4819_SetAF(BK4819_AF_BEEP);
	} else {
		BK4819_SetAF(BK4819_AF_MUTE);
	}
	BK4819_EnableTXLink();
	SYSTEM_DelayMs(50);
	BK4819_ExitTxMute();
}

void BK4819_GenTail(uint8_t Tail)
{
	switch(Tail) {
	case 0: // CTC134
		BK4819_WriteRegister(BK4819_REG_52, 0x828F);
		break;
	case 1: // CTC120
		BK4819_WriteRegister(BK4819_REG_52, 0xA28F);
		break;
	case 2: // CTC180
		BK4819_WriteRegister(BK4819_REG_52, 0xC28F);
		break;
	case 3: // CTC240
		BK4819_WriteRegister(BK4819_REG_52, 0xE28F);
		break;
	case 4: // CTC55
		BK4819_WriteRegister(BK4819_REG_07, 0x046f);
		break;
	}
}

void BK4819_EnableCDCSS(void)
{
	BK4819_GenTail(0); // CTC134
	BK4819_WriteRegister(BK4819_REG_51, 0x804A);
}

void BK4819_EnableCTCSS(void)
{
	BK4819_GenTail(4); // CTC55
	BK4819_WriteRegister(BK4819_REG_51, 0x904A);
}

uint16_t BK4819_GetRSSI(void)
{
	return BK4819_GetRegister(BK4819_REG_67) & 0x01FF;
}

bool BK4819_GetFrequencyScanResult(int32_t *pFrequency)
{
	uint16_t High, Low;
	bool Finished;

	High = BK4819_GetRegister(BK4819_REG_0D);
	Finished = (High & 0x8000) == 0;
	if (Finished) {
		Low = BK4819_GetRegister(BK4819_REG_0E);
		*pFrequency = ((High & 0x7FF) << 16) | Low;
	}

	return Finished;
}

BK4819_CssScanResult_t BK4819_GetCxCSSScanResult(int32_t *pCdcssFreq, uint16_t *pCtcssFreq)
{
	uint16_t High, Low;

	High = BK4819_GetRegister(BK4819_REG_69);
	if ((High & 0x8000) == 0) {
		Low = BK4819_GetRegister(BK4819_REG_6A);
		*pCdcssFreq = ((High & 0xFFF) << 12) | (Low & 0xFFF);
		return BK4819_CSS_RESULT_CDCSS;
	}

	Low = BK4819_GetRegister(BK4819_REG_68);
	if ((Low & 0x8000) == 0) {
		*pCtcssFreq = (Low & 0x1FFF) * 4843 / 10000;
		return BK4819_CSS_RESULT_CTCSS;
	}

	return BK4819_CSS_RESULT_NOT_FOUND;
}

void BK4819_DisableFrequencyScan(void)
{
	BK4819_WriteRegister(BK4819_REG_32, 0x0244);
}

void BK4819_EnableFrequencyScan(void)
{
	BK4819_WriteRegister(BK4819_REG_32, 0x0245);
}

void BK4819_SetScanFrequency(int32_t Frequency)
{
	BK4819_SetFrequency(Frequency);
	BK4819_WriteRegister(BK4819_REG_51, 0
		| BK4819_REG_51_DISABLE_CxCSS
		| BK4819_REG_51_GPIO6_PIN2_NORMAL
		| BK4819_REG_51_TX_CDCSS_POSITIVE
		| BK4819_REG_51_MODE_CDCSS
		| BK4819_REG_51_CDCSS_23_BIT
		| BK4819_REG_51_1050HZ_NO_DETECTION
		| BK4819_REG_51_AUTO_CDCSS_BW_DISABLE
		| BK4819_REG_51_AUTO_CTCSS_BW_DISABLE
		);
	BK4819_RX_TurnOn();
}

void BK4819_Disable(void)
{
	BK4819_WriteRegister(BK4819_REG_30, 0);
}

void BK4819_StopScan(void)
{
        BK4819_DisableFrequencyScan();
        BK4819_Disable();
}

uint8_t BK4819_GetDTMF_5TONE_Code(void)
{
        return (BK4819_GetRegister(BK4819_REG_0B) >> 8) & 0x0F;
}

uint8_t BK4819_CheckCDCSSCodeReceived(void)
{
        return (BK4819_GetRegister(BK4819_REG_0C) >> 14) & 3;
}