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/* mbed Microcontroller Library
* Copyright (c) 2013 Nordic Semiconductor
*
* 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.
*/
// math.h required for floating point operations for baud rate calculation
//#include <math.h>
#include <string.h>
#include "mbed_assert.h"
#include "serial_api.h"
#include "cmsis.h"
#include "pinmap.h"
/******************************************************************************
* INITIALIZATION
******************************************************************************/
#define UART_NUM 1
static uint32_t serial_irq_ids[UART_NUM] = {0};
static uart_irq_handler irq_handler;
static const int acceptedSpeeds[17][2] = {
{1200, UART_BAUDRATE_BAUDRATE_Baud1200},
{2400, UART_BAUDRATE_BAUDRATE_Baud2400},
{4800, UART_BAUDRATE_BAUDRATE_Baud4800},
{9600, UART_BAUDRATE_BAUDRATE_Baud9600},
{14400, UART_BAUDRATE_BAUDRATE_Baud14400},
{19200, UART_BAUDRATE_BAUDRATE_Baud19200},
{28800, UART_BAUDRATE_BAUDRATE_Baud28800},
{31250, (0x00800000UL) /* 31250 baud */},
{38400, UART_BAUDRATE_BAUDRATE_Baud38400},
{57600, UART_BAUDRATE_BAUDRATE_Baud57600},
{76800, UART_BAUDRATE_BAUDRATE_Baud76800},
{115200, UART_BAUDRATE_BAUDRATE_Baud115200},
{230400, UART_BAUDRATE_BAUDRATE_Baud230400},
{250000, UART_BAUDRATE_BAUDRATE_Baud250000},
{460800, UART_BAUDRATE_BAUDRATE_Baud460800},
{921600, UART_BAUDRATE_BAUDRATE_Baud921600},
{1000000, UART_BAUDRATE_BAUDRATE_Baud1M}
};
int stdio_uart_inited = 0;
serial_t stdio_uart;
void serial_init(serial_t *obj, PinName tx, PinName rx) {
UARTName uart = UART_0;
obj->uart = (NRF_UART_Type *)uart;
//pin configurations --
NRF_GPIO->DIR |= (1 << tx); //TX_PIN_NUMBER);
NRF_GPIO->DIR |= (1 << RTS_PIN_NUMBER);
NRF_GPIO->DIR &= ~(1 << rx); //RX_PIN_NUMBER);
NRF_GPIO->DIR &= ~(1 << CTS_PIN_NUMBER);
// set default baud rate and format
serial_baud (obj, 9600);
serial_format(obj, 8, ParityNone, 1);
obj->uart->ENABLE = (UART_ENABLE_ENABLE_Enabled << UART_ENABLE_ENABLE_Pos);
obj->uart->TASKS_STARTTX = 1;
obj->uart->TASKS_STARTRX = 1;
obj->uart->EVENTS_RXDRDY = 0;
// dummy write needed or TXDRDY trails write rather than leads write.
// pins are disconnected so nothing is physically transmitted on the wire
obj->uart->TXD = 0;
obj->index = 0;
obj->uart->PSELRTS = RTS_PIN_NUMBER;
obj->uart->PSELTXD = tx; //TX_PIN_NUMBER;
obj->uart->PSELCTS = CTS_PIN_NUMBER;
obj->uart->PSELRXD = rx; //RX_PIN_NUMBER;
// set rx/tx pins in PullUp mode
if (tx != NC) {
pin_mode(tx, PullUp);
}
if (rx != NC) {
pin_mode(rx, PullUp);
}
if (uart == STDIO_UART) {
stdio_uart_inited = 1;
memcpy(&stdio_uart, obj, sizeof(serial_t));
}
}
void serial_free(serial_t *obj)
{
serial_irq_ids[obj->index] = 0;
}
// serial_baud
// set the baud rate, taking in to account the current SystemFrequency
void serial_baud(serial_t *obj, int baudrate)
{
if (baudrate<=1200) {
obj->uart->BAUDRATE = UART_BAUDRATE_BAUDRATE_Baud1200;
return;
}
for (int i = 1; i<17; i++) {
if (baudrate<acceptedSpeeds[i][0]) {
obj->uart->BAUDRATE = acceptedSpeeds[i - 1][1];
return;
}
}
obj->uart->BAUDRATE = UART_BAUDRATE_BAUDRATE_Baud1M;
}
void serial_format(serial_t *obj, int data_bits, SerialParity parity, int stop_bits)
{
// 0: 1 stop bits, 1: 2 stop bits
// int parity_enable, parity_select;
switch (parity) {
case ParityNone:
obj->uart->CONFIG = 0;
break;
default:
obj->uart->CONFIG = (UART_CONFIG_PARITY_Included << UART_CONFIG_PARITY_Pos);
return;
}
//no Flow Control
}
//******************************************************************************
// * INTERRUPT HANDLING
//******************************************************************************
static inline void uart_irq(uint32_t iir, uint32_t index)
{
SerialIrq irq_type;
switch (iir) {
case 1:
irq_type = TxIrq;
break;
case 2:
irq_type = RxIrq;
break;
default:
return;
}
if (serial_irq_ids[index] != 0) {
irq_handler(serial_irq_ids[index], irq_type);
}
}
#ifdef __cplusplus
extern "C" {
#endif
void UART0_IRQHandler()
{
uint32_t irtype = 0;
if((NRF_UART0->INTENSET & 0x80) && NRF_UART0->EVENTS_TXDRDY) {
irtype = 1;
} else if((NRF_UART0->INTENSET & 0x04) && NRF_UART0->EVENTS_RXDRDY) {
irtype = 2;
}
uart_irq(irtype, 0);
}
#ifdef __cplusplus
}
#endif
void serial_irq_handler(serial_t *obj, uart_irq_handler handler, uint32_t id)
{
irq_handler = handler;
serial_irq_ids[obj->index] = id;
}
void serial_irq_set(serial_t *obj, SerialIrq irq, uint32_t enable)
{
IRQn_Type irq_n = (IRQn_Type)0;
switch ((int)obj->uart) {
case UART_0:
irq_n = UART0_IRQn;
break;
}
if (enable) {
switch (irq) {
case RxIrq:
obj->uart->INTENSET = (UART_INTENSET_RXDRDY_Msk);
break;
case TxIrq:
obj->uart->INTENSET = (UART_INTENSET_TXDRDY_Msk);
break;
}
NVIC_SetPriority(irq_n, 3);
NVIC_EnableIRQ(irq_n);
} else { // disable
// maseked writes to INTENSET dont disable and masked writes to
// INTENCLR seemed to clear the entire register, not bits.
// Added INTEN to memory map and seems to allow set and clearing of specific bits as desired
int all_disabled = 0;
switch (irq) {
case RxIrq:
obj->uart->INTENCLR = (UART_INTENCLR_RXDRDY_Msk);
all_disabled = (obj->uart->INTENCLR & (UART_INTENCLR_TXDRDY_Msk)) == 0;
break;
case TxIrq:
obj->uart->INTENCLR = (UART_INTENCLR_TXDRDY_Msk);
all_disabled = (obj->uart->INTENCLR & (UART_INTENCLR_RXDRDY_Msk)) == 0;
break;
}
if (all_disabled) {
NVIC_DisableIRQ(irq_n);
}
}
}
//******************************************************************************
//* READ/WRITE
//******************************************************************************
int serial_getc(serial_t *obj)
{
while (!serial_readable(obj)) {
}
obj->uart->EVENTS_RXDRDY = 0;
return (uint8_t)obj->uart->RXD;
}
void serial_putc(serial_t *obj, int c)
{
while (!serial_writable(obj)) {
}
obj->uart->EVENTS_TXDRDY = 0;
obj->uart->TXD = (uint8_t)c;
}
int serial_readable(serial_t *obj)
{
return (obj->uart->EVENTS_RXDRDY == 1);
}
int serial_writable(serial_t *obj)
{
return (obj->uart->EVENTS_TXDRDY == 1);
}
void serial_break_set(serial_t *obj)
{
obj->uart->TASKS_SUSPEND = 1;
}
void serial_break_clear(serial_t *obj)
{
obj->uart->TASKS_STARTTX = 1;
obj->uart->TASKS_STARTRX = 1;
}
void serial_set_flow_control(serial_t *obj, FlowControl type, PinName rxflow, PinName txflow)
{
if (type == FlowControlRTSCTS || type == FlowControlRTS) {
NRF_GPIO->DIR |= (1<<rxflow);
pin_mode(rxflow, PullUp);
obj->uart->PSELRTS = rxflow;
obj->uart->CONFIG |= 0x01; // Enable HWFC
}
if (type == FlowControlRTSCTS || type == FlowControlCTS) {
NRF_GPIO->DIR &= ~(1<<txflow);
pin_mode(txflow, PullUp);
obj->uart->PSELCTS = txflow;
obj->uart->CONFIG |= 0x01; // Enable HWFC;
}
if (type == FlowControlNone) {
obj->uart->PSELRTS = 0xFFFFFFFF; // Disable RTS
obj->uart->PSELCTS = 0xFFFFFFFF; // Disable CTS
obj->uart->CONFIG &= ~0x01; // Enable HWFC;
}
}
void serial_clear(serial_t *obj) {
}