Diff: Wire.cpp

Revision:

0:db8030e71f55

diff -r 000000000000 -r db8030e71f55 Wire.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Wire.cpp	Tue Sep 13 06:01:19 2016 +0000
@@ -0,0 +1,391 @@
+/*
+ * TwoWire.h
+ * Copyright (c) 2011 Cristian Maglie <c.maglie@bug.st>.
+ * All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+extern "C" {
+#include <string.h>
+}
+
+#include "Wire.h"
+
+
+
+#define EVENT_TIMEOUT       100
+
+
+TwoWire::TwoWire(I2C_TypeDef *_twi) :
+	twi(_twi), rxBufferIndex(0), rxBufferLength(0), txAddress(0),
+			txBufferLength(0), srvBufferIndex(0), srvBufferLength(0), status(
+					UNINITIALIZED){
+	// Empty
+}
+
+void TwoWire::begin(void) {
+	if (onBeginCallback)
+		onBeginCallback();
+
+	if (twi==I2C1)
+	{
+		RCC_I2CCLKConfig(RCC_I2C1CLK_HSI);
+		RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
+
+		pinMode(SDA, ALTERNATE);
+		pinMode(SCL, ALTERNATE);
+	} 
+	else if (twi == I2C2) 
+	{
+		RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C2, ENABLE);
+
+		pinMode(SDA1, ALTERNATE);
+		pinMode(SCL1, ALTERNATE);
+	}
+
+
+	I2C_DeInit(twi);
+
+	I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
+	I2C_InitStructure.I2C_AnalogFilter = I2C_AnalogFilter_Enable;
+	I2C_InitStructure.I2C_DigitalFilter = 0x00;
+	if (status == UNINITIALIZED)
+	{
+		I2C_InitStructure.I2C_OwnAddress1 = 0x00;
+		status = MASTER_IDLE;
+	}
+	I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
+	I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
+	I2C_InitStructure.I2C_Timing = 0x00E0D3FF;
+	I2C_Init(twi, &I2C_InitStructure);
+
+	I2C_Cmd(twi, ENABLE);
+
+	
+}
+
+void TwoWire::begin(uint8_t address) {
+	if (onBeginCallback)
+		onBeginCallback();
+	status = SLAVE_IDLE;
+	if (twi==I2C1)
+	{
+		RCC_I2CCLKConfig(RCC_I2C1CLK_HSI);
+		RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
+
+		pinMode(SDA, ALTERNATE);
+		pinMode(SCL, ALTERNATE);
+	}
+
+
+	I2C_DeInit(twi);
+
+	I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
+	I2C_InitStructure.I2C_AnalogFilter = I2C_AnalogFilter_Enable;
+	I2C_InitStructure.I2C_DigitalFilter = 0x00;
+		I2C_InitStructure.I2C_OwnAddress1 = address;
+	I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
+	I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
+	I2C_InitStructure.I2C_Timing = 0x00E0D3FF;
+	I2C_Init(twi, &I2C_InitStructure);
+
+	NVIC_SetPriority(I2C1_IRQn, 0);
+	NVIC_EnableIRQ(I2C1_IRQn);   
+	I2C_Cmd(twi, ENABLE);
+	I2C_ITConfig(twi, I2C_IT_ADDRI, ENABLE);
+}
+
+void TwoWire::begin(int address) {
+	address <<= 1;
+	begin((uint8_t) address);
+}
+
+uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity, uint8_t sendStop) {
+	address <<= 1;
+	if (quantity > BUFFER_LENGTH)
+		quantity = BUFFER_LENGTH;
+	uint32_t _millis;
+	
+	_millis = millis();
+	while(I2C_GetFlagStatus(twi, I2C_FLAG_BUSY) != RESET)
+	{
+		if(EVENT_TIMEOUT < (millis() - _millis)) return 0;
+	}
+
+	I2C_TransferHandling(twi, address, quantity, I2C_AutoEnd_Mode, I2C_Generate_Start_Read);
+
+	
+	uint8_t *pBuffer = rxBuffer;
+	uint8_t numByteToRead = quantity;
+	uint8_t bytesRead = 0;	
+	/* While there is data to be read */
+	while(numByteToRead)
+	{
+		_millis = millis();
+		while(I2C_GetFlagStatus(twi, I2C_FLAG_RXNE) == RESET)
+		{
+			if(EVENT_TIMEOUT < (millis() - _millis)) return 0;
+		}
+		/* Read a byte from the Slave */
+		*pBuffer = I2C_ReceiveData(twi);
+			
+		bytesRead++;
+
+		/* Point to the next location where the byte read will be saved */
+		pBuffer++;
+
+		/* Decrement the read bytes counter */
+		numByteToRead--;		
+	}
+	_millis = millis();
+	while(I2C_GetFlagStatus(twi, I2C_FLAG_STOPF) == RESET)
+	{
+		if(EVENT_TIMEOUT < (millis() - _millis)) return 0;
+	}
+	// set rx buffer iterator vars
+	rxBufferIndex = 0;
+	rxBufferLength = bytesRead;
+	
+	return bytesRead;
+}
+
+uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity) {
+	return requestFrom((uint8_t) address, (uint8_t) quantity, (uint8_t) true);
+}
+
+uint8_t TwoWire::requestFrom(int address, int quantity) {
+	return requestFrom((uint8_t) address, (uint8_t) quantity, (uint8_t) true);
+}
+
+uint8_t TwoWire::requestFrom(int address, int quantity, int sendStop) {
+	return requestFrom((uint8_t) address, (uint8_t) quantity, (uint8_t) sendStop);
+}
+
+void TwoWire::beginTransmission(uint8_t address) {
+	status = MASTER_SEND;
+
+	// save address of target and empty buffer
+	txAddress = address;
+	txBufferLength = 0;
+}
+
+void TwoWire::beginTransmission(int address) {
+	address <<= 1;
+	beginTransmission((uint8_t) address);
+}
+
+//
+//	Originally, 'endTransmission' was an f(void) function.
+//	It has been modified to take one parameter indicating
+//	whether or not a STOP should be performed on the bus.
+//	Calling endTransmission(false) allows a sketch to
+//	perform a repeated start.
+//
+//	WARNING: Nothing in the library keeps track of whether
+//	the bus tenure has been properly ended with a STOP. It
+//	is very possible to leave the bus in a hung state if
+//	no call to endTransmission(true) is made. Some I2C
+//	devices will behave oddly if they do not see a STOP.
+//
+uint8_t TwoWire::endTransmission(uint8_t sendStop) {
+	uint32_t _millis;
+	
+	_millis = millis();
+	while(I2C_GetFlagStatus(twi, I2C_FLAG_BUSY) != RESET)
+	{
+		if(EVENT_TIMEOUT < (millis() - _millis)) return 0;
+	}
+	if (sendStop == true)
+	{
+		I2C_TransferHandling(twi, txAddress, txBufferLength, I2C_AutoEnd_Mode, I2C_Generate_Start_Write);
+	} 
+	else 
+	{
+		I2C_TransferHandling(twi, txAddress, txBufferLength, I2C_SoftEnd_Mode, I2C_Generate_Start_Write);
+	}	
+	uint8_t *pBuffer = txBuffer;
+	uint8_t NumByteToWrite = txBufferLength;
+	/* While there is data to be read */
+	while(NumByteToWrite--)
+	{
+		_millis = millis();
+		while(I2C_GetFlagStatus(twi, I2C_FLAG_TXIS) == RESET)
+		{
+			if(EVENT_TIMEOUT < (millis() - _millis)) return 0;
+		}
+		/* Send the current byte to slave */
+		I2C_SendData(twi, *pBuffer++);	
+	}
+	_millis = millis();
+	if (sendStop == true)
+	{
+		while(I2C_GetFlagStatus(twi, I2C_FLAG_STOPF) == RESET)
+		{
+			if(EVENT_TIMEOUT < (millis() - _millis)) return 0;
+		}
+	}
+	else
+	{
+		while(I2C_GetFlagStatus(twi, I2C_FLAG_STOPF) == RESET)
+		{
+			if(EVENT_TIMEOUT < (millis() - _millis)) return 0;
+		}	
+	}
+	// reset tx buffer iterator vars
+	txBufferLength = 0;
+
+	status = MASTER_IDLE;
+	return 0;
+}
+
+//	This provides backwards compatibility with the original
+//	definition, and expected behaviour, of endTransmission
+//
+uint8_t TwoWire::endTransmission(void)
+{
+	return endTransmission(true);
+}
+
+size_t TwoWire::write(uint8_t data) {
+	if (status == MASTER_SEND) {
+		if (txBufferLength >= BUFFER_LENGTH)
+			return 0;
+		txBuffer[txBufferLength++] = data;
+		return 1;
+	} else {
+		if (srvBufferLength >= BUFFER_LENGTH)
+			return 0;
+		srvBuffer[srvBufferLength++] = data;
+		return 1;
+	}
+}
+
+size_t TwoWire::write(const uint8_t *data, size_t quantity) {
+	if (status == MASTER_SEND) {
+		for (size_t i = 0; i < quantity; ++i) {
+			if (txBufferLength >= BUFFER_LENGTH)
+				return i;
+			txBuffer[txBufferLength++] = data[i];
+		}
+	} else {
+		for (size_t i = 0; i < quantity; ++i) {
+			if (srvBufferLength >= BUFFER_LENGTH)
+				return i;
+			srvBuffer[srvBufferLength++] = data[i];
+		}
+	}
+	return quantity;
+}
+
+int TwoWire::available(void) {
+	return rxBufferLength - rxBufferIndex;
+}
+
+int TwoWire::read(void) {
+	if (rxBufferIndex < rxBufferLength)
+		return rxBuffer[rxBufferIndex++];
+	return -1;
+}
+
+int TwoWire::peek(void) {
+	if (rxBufferIndex < rxBufferLength)
+		return rxBuffer[rxBufferIndex];
+	return -1;
+}
+
+void TwoWire::flush(void) {
+	// Do nothing, use endTransmission(..) to force
+	// data transfer.
+}
+
+void TwoWire::onReceive(void(*function)(int)) {
+	onReceiveCallback = function;
+}
+
+void TwoWire::onRequest(void(*function)(void)) {
+	onRequestCallback = function;
+}
+
+void TwoWire::onService(void) 
+{
+	if (I2C_GetITStatus(twi, I2C_IT_ADDR) == SET)
+	{
+		I2C_ITConfig(twi, I2C_IT_RXI | I2C_IT_TXI | I2C_IT_STOPI, ENABLE);
+		srvBufferLength = 0;
+		srvBufferIndex = 0;
+		if (twi->ISR & (1 << 16)) {
+			status = SLAVE_SEND;
+			if (onRequestCallback)
+				onRequestCallback();
+		} else {
+			status = SLAVE_RECV;
+		}
+
+		I2C_ClearITPendingBit(twi, I2C_IT_ADDR);
+	}
+	if (I2C_GetITStatus(twi, I2C_IT_TXIS) == SET)
+	{
+		uint8_t c = 'x';
+		if (srvBufferIndex < srvBufferLength)
+			c = srvBuffer[srvBufferIndex++];
+		I2C_SendData(twi, c);
+	}
+	if (I2C_GetITStatus(twi, I2C_IT_RXNE) == SET)
+	{
+		if (srvBufferLength < BUFFER_LENGTH)
+			srvBuffer[srvBufferLength++] = I2C_ReceiveData(twi);
+	}
+	if (I2C_GetITStatus(twi, I2C_IT_STOPF) == SET)
+	{
+		if (status == SLAVE_RECV && onReceiveCallback) {
+			// Copy data into rxBuffer
+			// (allows to receive another packet while the
+			// user program reads actual data)
+			for (uint8_t i = 0; i < srvBufferLength; ++i)
+				rxBuffer[i] = srvBuffer[i];
+			rxBufferIndex = 0;
+			rxBufferLength = srvBufferLength;
+			// Alert calling program
+			onReceiveCallback( rxBufferLength);
+		}
+		I2C_ITConfig(twi, I2C_IT_ADDRI, ENABLE);
+		I2C_ITConfig(twi, I2C_IT_RXI | I2C_IT_TXI | I2C_IT_STOPI, DISABLE);
+		I2C_ClearITPendingBit(twi, I2C_IT_STOPF);
+	}
+}
+
+
+
+
+TwoWire Wire = TwoWire(I2C1);
+TwoWire Wire1 = TwoWire(I2C2);
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+void WIRE_ISR_HANDLER(void) {
+	Wire.onService();
+}
+
+void WIRE1_ISR_HANDLER(void) {
+	Wire1.onService();
+}
+#ifdef __cplusplus
+}
+#endif
+
+
+