/******************************************************************************
* FunctionName : i2c_master_readByte
* Description : read Byte from i2c bus
* Parameters : NONE
* Returns : uint8 - readed value
*******************************************************************************/
uint8 i2c_master_readByte(void)
{
uint8 retVal = 0;
uint8 k, i;
i2c_master_setDC(1, m_nLastSCL);
for (i = 0; i < 8; i++) {
i2c_master_wait(I2C_SLEEP_TIME);
i2c_master_setDC(1, 0);
i2c_master_wait(I2C_SLEEP_TIME);// sda 1, scl 0
i2c_master_setDC(1, 1);
while(i2c_master_getCL()==0)
; // clock stretch
i2c_master_wait(I2C_SLEEP_TIME);// sda 1, scl 1
k = i2c_master_getDC();
i2c_master_wait(I2C_SLEEP_TIME);
//if (i == 7) {
// i2c_master_wait(5); ////
//}
k <<= (7 - i);
retVal |= k;
}
i2c_master_setDC(m_nLastSDA, 0);
i2c_master_wait(I2C_SLEEP_TIME);// sda 1, scl 0
return retVal;
}
/******************************************************************************
* FunctionName : i2c_master_start
* Description : set i2c to send state
* Parameters : NONE
* Returns : NONE
*******************************************************************************/
void ICACHE_FLASH_ATTR
i2c_master_start(void)
{
i2c_master_setDC(1, m_nLastSCL); // sda 1
i2c_master_setDC(1, 1); // sda 1, scl 1
i2c_master_setDC(0, 1); // sda 0, scl 1
}
/******************************************************************************
* FunctionName : i2c_master_init
* Description : initilize I2C bus to enable i2c operations
* Parameters : NONE
* Returns : NONE
*******************************************************************************/
void i2c_master_init(void)
{
uint8 i;
i2c_master_setDC(1, 0);
i2c_master_wait(I2C_SLEEP_TIME);
// when SCL = 0, toggle SDA to clear up
i2c_master_setDC(0, 0) ;
i2c_master_wait(I2C_SLEEP_TIME);
i2c_master_setDC(1, 0) ;
i2c_master_wait(I2C_SLEEP_TIME);
// set data_cnt to max value
for (i = 0; i < 28; i++) {
i2c_master_setDC(1, 0);
i2c_master_wait(I2C_SLEEP_TIME);// sda 1, scl 0
i2c_master_setDC(1, 1);
i2c_master_wait(I2C_SLEEP_TIME);// sda 1, scl 1
}
// reset all
i2c_master_stop();
return;
}
/******************************************************************************
* FunctionName : i2c_master_init
* Description : initilize I2C bus to enable i2c operations
* Parameters : NONE
* Returns : NONE
*******************************************************************************/
void ICACHE_FLASH_ATTR i2c_master_init(void)
{
uint8 i;
i2c_master_setDC(1, 0);
i2c_master_wait(I2C_DELAY_FULL);
// when SCL = 0, toggle SDA to clear up
i2c_master_setDC(0, 0) ;
i2c_master_wait(I2C_DELAY_FULL);
i2c_master_setDC(1, 0) ;
i2c_master_wait(I2C_DELAY_FULL);
// set data_cnt to max value
for (i = 0; i < 28; i++) {
i2c_master_setDC(1, 0);
i2c_master_wait(I2C_DELAY_FULL); // sda 1, scl 0
i2c_master_setDC(1, 1);
i2c_master_wait(I2C_DELAY_FULL); // sda 1, scl 1
}
// reset all
i2c_master_stop();
return;
}
/******************************************************************************
* FunctionName : i2c_master_readByte
* Description : read Byte from i2c bus
* Parameters : NONE
* Returns : uint8 - readed value
*******************************************************************************/
uint8 ICACHE_FLASH_ATTR
i2c_master_readByte(void)
{
uint8 retVal = 0;
uint8 k, i;
i2c_master_wait(5);
i2c_master_setDC(m_nLastSDA, 0);
i2c_master_wait(5); // sda 1, scl 0
for (i = 0; i < 8; i++) {
i2c_master_wait(5);
i2c_master_setDC(1, 0);
i2c_master_wait(5); // sda 1, scl 0
i2c_master_setDC(1, 1);
i2c_master_wait(5); // sda 1, scl 1
k = i2c_master_getDC();
i2c_master_wait(5);
if (i == 7) {
i2c_master_wait(3); ////
}
k <<= (7 - i);
retVal |= k;
}
i2c_master_setDC(1, 0);
i2c_master_wait(5); // sda 1, scl 0
return retVal;
}
/******************************************************************************
* FunctionName : i2c_master_writeByte
* Description : write wrdata value(one byte) into i2c
* Parameters : uint8 wrdata - write value
* Returns : NONE
*******************************************************************************/
void ICACHE_FLASH_ATTR
i2c_master_writeByte(uint8 wrdata)
{
uint8 dat;
sint8 i;
i2c_master_wait(5);
i2c_master_setDC(m_nLastSDA, 0);
i2c_master_wait(5);
for (i = 7; i >= 0; i--) {
dat = wrdata >> i;
i2c_master_setDC(dat, 0);
i2c_master_wait(5);
i2c_master_setDC(dat, 1);
i2c_master_wait(5);
if (i == 0) {
i2c_master_wait(3); ////
}
i2c_master_setDC(dat, 0);
i2c_master_wait(5);
}
}
/******************************************************************************
* FunctionName : i2c_master_writeByte
* Description : write wrdata value(one byte) into i2c
* Parameters : uint8 wrdata - write value
* Returns : NONE
*******************************************************************************/
void i2c_master_writeByte(uint8 wrdata)
{
uint8 dat;
sint8 i;
/*
i2c_master_wait(I2C_SLEEP_TIME);
i2c_master_setDC(m_nLastSDA, 0);
*/
i2c_master_wait(I2C_SLEEP_TIME);
for (i = 7; i >= 0; i--) {
dat = wrdata >> i;
i2c_master_setDC(dat, 0);
i2c_master_wait(I2C_SLEEP_TIME);
i2c_master_setDC(dat, 1);
i2c_master_wait(I2C_SLEEP_TIME);
/*
if (i == 0) {
i2c_master_wait(5); ////
}
*/
i2c_master_setDC(dat, 0);
i2c_master_wait(I2C_SLEEP_TIME);
}
}
/******************************************************************************
* FunctionName : i2c_master_start
* Description : set i2c to send state
* Parameters : NONE
* Returns : NONE
*******************************************************************************/
void i2c_master_start(void)
{
i2c_master_setDC(1, m_nLastSCL);
i2c_master_wait(I2C_SLEEP_TIME);
i2c_master_setDC(1, 1);
i2c_master_wait(I2C_SLEEP_TIME);// sda 1, scl 1
i2c_master_setDC(0, 1);
i2c_master_wait(I2C_SLEEP_TIME);// sda 0, scl 1
}
/******************************************************************************
* FunctionName : i2c_master_stop
* Description : set i2c to stop sending state
* Parameters : NONE
* Returns : NONE
*******************************************************************************/
void ICACHE_FLASH_ATTR
i2c_master_stop(void)
{
i2c_master_wait(I2C_DELAY);
i2c_master_setDC(0, m_nLastSCL); // sda 0
i2c_master_setDC(0, 1); // sda 0, scl 1
i2c_master_setDC(1, 1); // sda 1, scl 1
}
/******************************************************************************
* FunctionName : i2c_master_start
* Description : set i2c to send state
* Parameters : NONE
* Returns : NONE
*******************************************************************************/
void ICACHE_RAM_ATTR
i2c_master_start(void)
{
i2c_master_setDC(1, m_nLastSCL);
i2c_master_wait(5);
i2c_master_setDC(1, 1);
i2c_master_wait(5); // sda 1, scl 1
i2c_master_setDC(0, 1);
i2c_master_wait(5); // sda 0, scl 1
}
/******************************************************************************
* FunctionName : i2c_master_setAck
* Description : set ack to i2c bus as level value
* Parameters : uint8 level - 0 or 1
* Returns : NONE
*******************************************************************************/
void ICACHE_FLASH_ATTR
i2c_master_setAck(uint8 level)
{
i2c_master_setDC(m_nLastSDA, 0);
i2c_master_setDC(level, 0); // sda level, scl 0
i2c_master_setDC(level, 1); // sda level, scl 1
i2c_master_wait(I2C_DELAY); // extra delay
i2c_master_setDC(level, 0); // sda level, scl 0
i2c_master_setDC(1, 0);
}
/******************************************************************************
* FunctionName : i2c_master_setAck
* Description : set ack to i2c bus as level value
* Parameters : uint8 level - 0 or 1
* Returns : NONE
*******************************************************************************/
void ICACHE_FLASH_ATTR
i2c_master_setAck(uint8 level)
{
i2c_master_setDC(level, 0);
i2c_master_wait(2); // sda level, scl 0
i2c_master_setDC(level, 1);
i2c_master_wait(4); // sda level, scl 1
i2c_master_setDC(level, 0);
i2c_master_wait(2); // sda level, scl 0
i2c_master_setDC(1, 0);
i2c_master_wait(2);
}
/******************************************************************************
* FunctionName : i2c_master_setAck
* Description : set ack to i2c bus as level value
* Parameters : uint8 level - 0 or 1
* Returns : NONE
*******************************************************************************/
void i2c_master_setAck(uint8 level)
{
i2c_master_setDC(m_nLastSDA, 0);
i2c_master_wait(I2C_SLEEP_TIME);
i2c_master_setDC(level, 0);
i2c_master_wait(I2C_SLEEP_TIME);// sda level, scl 0
i2c_master_setDC(level, 1);
i2c_master_wait(8);// sda level, scl 1
i2c_master_setDC(level, 0);
i2c_master_wait(I2C_SLEEP_TIME);// sda level, scl 0
i2c_master_setDC(1, 0);
i2c_master_wait(I2C_SLEEP_TIME);
}
/******************************************************************************
* FunctionName : i2c_master_setAck
* Description : set ack to i2c bus as level value
* Parameters : uint8 level - 0 or 1
* Returns : NONE
*******************************************************************************/
void ICACHE_FLASH_ATTR
i2c_master_setAck(uint8 level)
{
i2c_master_setDC(m_nLastSDA, 0);
i2c_master_wait(5);
i2c_master_setDC(level, 0);
i2c_master_wait(5); // sda level, scl 0
i2c_master_setDC(level, 1);
i2c_master_wait(8); // sda level, scl 1
i2c_master_setDC(level, 0);
i2c_master_wait(5); // sda level, scl 0
i2c_master_setDC(1, 0);
i2c_master_wait(5);
}
/******************************************************************************
* FunctionName : i2c_master_getAck
* Description : confirm if peer send ack
* Parameters : NONE
* Returns : uint8 - ack value, 0 or 1
*******************************************************************************/
uint8 ICACHE_FLASH_ATTR
i2c_master_getAck(void)
{
uint8 retVal;
i2c_master_setDC(1, 0);
i2c_master_wait(2);
i2c_master_setDC(1, 1);
i2c_master_wait(4);
retVal = i2c_master_getDC();
i2c_master_setDC(1, 0);
i2c_master_wait(2);
return !retVal; // 0->true->ACK, 1->false->NACK
}
/******************************************************************************
* FunctionName : i2c_master_getAck
* Description : confirm if peer send ack
* Parameters : NONE
* Returns : uint8 - ack value, 0 or 1
*******************************************************************************/
uint8 ICACHE_FLASH_ATTR
i2c_master_getAck(void)
{
uint8 retVal;
i2c_master_setDC(m_nLastSDA, 0);
i2c_master_setDC(1, 0);
i2c_master_wait(I2C_DELAY); // extra delay
i2c_master_setDC(1, 1);
retVal = i2c_master_getDC();
i2c_master_setDC(1, 0);
return retVal;
}
/******************************************************************************
* FunctionName : i2c_master_gpio_init
* Description : config SDA and SCL gpio to open-drain output mode,
* mux and gpio num defined in i2c_master.h
* Parameters : uint8 sda and scl pin numbers
* Returns : bool, true if init okay
*******************************************************************************/
bool i2c_master_gpio_init(uint8 sda, uint8 scl)
{
if((sda > GPIO_PIN_NUM) || (pin_func[sda] == GPIO_PIN_FUNC_INVALID)){
return false;
}
if((scl > GPIO_PIN_NUM) || (pin_func[scl] == GPIO_PIN_FUNC_INVALID)){
return false;
}
pinSDA = sda;
pinSCL = scl;
ETS_GPIO_INTR_DISABLE() ;
// ETS_INTR_LOCK();
PIN_FUNC_SELECT(pin_mux[sda], pin_func[sda]);
PIN_FUNC_SELECT(pin_mux[scl], pin_func[scl]);
GPIO_REG_WRITE(GPIO_PIN_ADDR(GPIO_ID_PIN(sda)), GPIO_REG_READ(GPIO_PIN_ADDR(GPIO_ID_PIN(sda))) | GPIO_PIN_PAD_DRIVER_SET(GPIO_PAD_DRIVER_ENABLE)); //open drain;
GPIO_REG_WRITE(GPIO_ENABLE_ADDRESS, GPIO_REG_READ(GPIO_ENABLE_ADDRESS) | (1 << sda));
GPIO_REG_WRITE(GPIO_PIN_ADDR(GPIO_ID_PIN(scl)), GPIO_REG_READ(GPIO_PIN_ADDR(GPIO_ID_PIN(scl))) | GPIO_PIN_PAD_DRIVER_SET(GPIO_PAD_DRIVER_ENABLE)); //open drain;
GPIO_REG_WRITE(GPIO_ENABLE_ADDRESS, GPIO_REG_READ(GPIO_ENABLE_ADDRESS) | (1 << scl));
i2c_master_setDC(1, 1);
ETS_GPIO_INTR_ENABLE() ;
// ETS_INTR_UNLOCK();
i2c_master_init();
return true;
}
/******************************************************************************
* FunctionName : i2c_master_getAck
* Description : confirm if peer send ack
* Parameters : NONE
* Returns : uint8 - ack value, 0 or 1
*******************************************************************************/
uint8 i2c_master_getAck(void)
{
uint8 retVal;
i2c_master_setDC(m_nLastSDA, 0);
i2c_master_wait(I2C_SLEEP_TIME);
i2c_master_setDC(1, 0);
i2c_master_wait(I2C_SLEEP_TIME);
i2c_master_setDC(1, 1);
i2c_master_wait(I2C_SLEEP_TIME);
retVal = i2c_master_getDC();
i2c_master_wait(I2C_SLEEP_TIME);
i2c_master_setDC(1, 0);
i2c_master_wait(I2C_SLEEP_TIME);
return retVal;
}
/******************************************************************************
* FunctionName : i2c_master_getAck
* Description : confirm if peer send ack
* Parameters : NONE
* Returns : uint8 - ack value, 0 or 1
*******************************************************************************/
uint8 ICACHE_FLASH_ATTR
i2c_master_getAck(void)
{
uint8 retVal;
i2c_master_setDC(m_nLastSDA, 0);
i2c_master_wait(5);
i2c_master_setDC(1, 0);
i2c_master_wait(5);
i2c_master_setDC(1, 1);
i2c_master_wait(5);
retVal = i2c_master_getDC();
i2c_master_wait(5);
i2c_master_setDC(1, 0);
i2c_master_wait(5);
return retVal;
}
/******************************************************************************
* FunctionName : i2c_master_writeByte
* Description : write wrdata value(one byte) into i2c
* Parameters : uint8 wrdata - write value
* Returns : NONE
*******************************************************************************/
void ICACHE_RAM_ATTR
i2c_master_writeByte(uint8 wrdata)
{
uint8 dat;
sint8 i;
i2c_master_wait(2);
i2c_master_setDC(m_nLastSDA, 0);
i2c_master_wait(4);
for (i = 7; i >= 0; i--) {
dat = wrdata >> i;
i2c_master_setDC(dat, 0);
i2c_master_wait(2);
i2c_master_setDC(dat, 1);
i2c_master_wait(4);
i2c_master_setDC(dat, 0);
i2c_master_wait(1);
}
}
/******************************************************************************
* FunctionName : i2c_master_writeByte
* Description : write wrdata value(one byte) into i2c
* Parameters : uint8 wrdata - write value
* Returns : NONE
*******************************************************************************/
void ICACHE_FLASH_ATTR
i2c_master_writeByte(uint8 wrdata)
{
uint8 dat;
sint8 i;
i2c_master_wait(I2C_DELAY); // extra delay
i2c_master_setDC(m_nLastSDA, 0);
for (i = 7; i >= 0; i--) {
dat = wrdata >> i;
i2c_master_setDC(dat, 0);
i2c_master_setDC(dat, 1);
i2c_master_wait(I2C_DELAY); // extra delay
if (i == 0) {
i2c_master_wait(I2C_DELAY); // extra delay
}
i2c_master_setDC(dat, 0);
}
}
/******************************************************************************
* FunctionName : i2c_master_readByte
* Description : read Byte from i2c bus
* Parameters : NONE
* Returns : uint8 - readed value
*******************************************************************************/
uint8 ICACHE_FLASH_ATTR
i2c_master_readByte(void)
{
uint8 retVal = 0;
uint8 i;
i2c_master_wait(2);
i2c_master_setDC(m_nLastSDA, 0);
i2c_master_wait(4); // sda 1, scl 0
for (i = 0; i < 8; i++) {
i2c_master_setDC(1, 0);
i2c_master_wait(4); // sda 1, scl 0
i2c_master_setDC(1, 1);
i2c_master_wait(3); // sda 1, scl 1
retVal = (retVal<<1) | (i2c_master_getDC()&1);
}
i2c_master_setDC(1, 0);
i2c_master_wait(2); // sda 1, scl 0
return retVal;
}
bool i2c_master_readBytes(uint8 address, uint8 *values, uint8 length)
{
if(values[0] > 0){
if(!i2c_master_writeBytes(address, values, 1)){
return false;
}
}
uint8 timeout = 100;
do{
i2c_master_start();
i2c_master_writeByte(address+1);
if(!i2c_master_checkAck()){
i2c_master_stop();
i2c_master_wait(1000);
continue;
}
break;
}while(--timeout>0);
if(timeout == 0){
return false;
}
#ifdef CONFIG_I2C_MASTER_DEBUG
console_printf("Read: ");
#endif
uint8 readed = 0;
while((readed < length) && (--timeout>0)){
uint8 byte = i2c_master_readByte();
values[readed++] = byte;
i2c_master_setAck((readed == length)); // send the ACK or NAK as applicable
i2c_master_setDC(1, 0); // release SDA
#ifdef CONFIG_I2C_MASTER_DEBUG
console_printf("%d ", byte);
#endif
}
#ifdef CONFIG_I2C_MASTER_DEBUG
console_printf("\n");
#endif
i2c_master_stop();
return true;
}
