added prescaler for 16 bit pwm in LPC1347 target
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Diff: common/I2C.cpp
- Revision:
- 0:9b334a45a8ff
- Child:
- 144:ef7eb2e8f9f7
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/common/I2C.cpp Thu Oct 01 15:25:22 2015 +0300 @@ -0,0 +1,128 @@ +/* mbed Microcontroller Library + * Copyright (c) 2006-2015 ARM Limited + * + * 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 "I2C.h" + +#if DEVICE_I2C + +namespace mbed { + +I2C *I2C::_owner = NULL; + +I2C::I2C(PinName sda, PinName scl) : +#if DEVICE_I2C_ASYNCH + _irq(this), _usage(DMA_USAGE_NEVER), +#endif + _i2c(), _hz(100000) { + // The init function also set the frequency to 100000 + i2c_init(&_i2c, sda, scl); + + // Used to avoid unnecessary frequency updates + _owner = this; +} + +void I2C::frequency(int hz) { + _hz = hz; + + // We want to update the frequency even if we are already the bus owners + i2c_frequency(&_i2c, _hz); + + // Updating the frequency of the bus we become the owners of it + _owner = this; +} + +void I2C::aquire() { + if (_owner != this) { + i2c_frequency(&_i2c, _hz); + _owner = this; + } +} + +// write - Master Transmitter Mode +int I2C::write(int address, const char* data, int length, bool repeated) { + aquire(); + + int stop = (repeated) ? 0 : 1; + int written = i2c_write(&_i2c, address, data, length, stop); + + return length != written; +} + +int I2C::write(int data) { + return i2c_byte_write(&_i2c, data); +} + +// read - Master Reciever Mode +int I2C::read(int address, char* data, int length, bool repeated) { + aquire(); + + int stop = (repeated) ? 0 : 1; + int read = i2c_read(&_i2c, address, data, length, stop); + + return length != read; +} + +int I2C::read(int ack) { + if (ack) { + return i2c_byte_read(&_i2c, 0); + } else { + return i2c_byte_read(&_i2c, 1); + } +} + +void I2C::start(void) { + i2c_start(&_i2c); +} + +void I2C::stop(void) { + i2c_stop(&_i2c); +} + +#if DEVICE_I2C_ASYNCH + +int I2C::transfer(int address, const char *tx_buffer, int tx_length, char *rx_buffer, int rx_length, const event_callback_t& callback, int event, bool repeated) +{ + if (i2c_active(&_i2c)) { + return -1; // transaction ongoing + } + aquire(); + + _callback = callback; + int stop = (repeated) ? 0 : 1; + _irq.callback(&I2C::irq_handler_asynch); + i2c_transfer_asynch(&_i2c, (void *)tx_buffer, tx_length, (void *)rx_buffer, rx_length, address, stop, _irq.entry(), event, _usage); + return 0; +} + +void I2C::abort_transfer(void) +{ + i2c_abort_asynch(&_i2c); +} + +void I2C::irq_handler_asynch(void) +{ + int event = i2c_irq_handler_asynch(&_i2c); + if (_callback && event) { + _callback.call(event); + } + +} + + +#endif + +} // namespace mbed + +#endif