MMDVM/STMUART.cpp

100 lines
2.4 KiB
C++

/*
* Copyright (c) 2020 by Jonathan Naylor G4KLX
* Copyright (c) 2020 by Geoffrey Merck F4FXL - KC3FRA
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#if defined(STM32F4XX) || defined(STM32F7XX)
#include "STMUART.h"
CSTMUART::CSTMUART() :
m_usart(NULL)
{
}
void CSTMUART::init(USART_TypeDef* usart)
{
m_usart = usart;
}
void CSTMUART::write(const uint8_t * data, uint16_t length)
{
if(length == 0U || m_usart == NULL)
return;
m_txFifo.put(data[0]);
USART_ITConfig(m_usart, USART_IT_TXE, ENABLE);//switch TX IRQ is on
for(uint16_t i = 1U; i < length; i++) {
m_txFifo.put(data[i]);
}
USART_ITConfig(m_usart, USART_IT_TXE, ENABLE);//make sure TX IRQ is on
}
uint8_t CSTMUART::read()
{
return m_rxFifo.get();
}
void CSTMUART::handleIRQ()
{
if(m_usart == NULL)
return;
if (USART_GetITStatus(m_usart, USART_IT_RXNE)) {
if(!m_rxFifo.isFull())
m_rxFifo.put((uint8_t) USART_ReceiveData(m_usart));
USART_ClearITPendingBit(USART1, USART_IT_RXNE);
}
if (USART_GetITStatus(m_usart, USART_IT_TXE)) {
if(!m_txFifo.isEmpty())
USART_SendData(m_usart, m_txFifo.get());
USART_ClearITPendingBit(m_usart, USART_IT_TXE);
if (m_txFifo.isEmpty()) // if there's no more data to transmit then turn off TX interrupts
USART_ITConfig(m_usart, USART_IT_TXE, DISABLE);
}
}
// Flushes the transmit shift register
// warning: this call is blocking
void CSTMUART::flush()
{
if(m_usart == NULL)
return;
// wait until the TXE shows the shift register is empty
while (USART_GetITStatus(m_usart, USART_FLAG_TXE))
;
}
uint16_t CSTMUART::available()
{
return m_rxFifo.isEmpty() ? 0U : 1U;
}
uint16_t CSTMUART::availableForWrite()
{
return m_txFifo.isFull() ? 0U : 1U;
}
#endif