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cpu/atmega2560: update atmega2560 CPU code to use atmega_common code

pr/spi.typo
kYc0o 7 years ago
parent
17c78e70e2
commit
be70924800
11 changed files with 6 additions and 955 deletions
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  1. 2
      cpu/atmega2560/Makefile
  2. 6
      cpu/atmega2560/Makefile.include
  3. 96
      cpu/atmega2560/include/atmega2560_regs.h
  4. 2
      cpu/atmega2560/include/cpu_conf.h
  5. 55
      cpu/atmega2560/include/periph_cpu.h
  6. 3
      cpu/atmega2560/periph/Makefile
  7. 257
      cpu/atmega2560/periph/gpio.c
  8. 145
      cpu/atmega2560/periph/spi.c
  9. 258
      cpu/atmega2560/periph/timer.c
  10. 133
      cpu/atmega2560/periph/uart.c
  11. 4
      cpu/atmega_common/Makefile

2
cpu/atmega2560/Makefile
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@ -1,5 +1,5 @@
# define the module that is build
MODULE = cpu
# add a list of subdirectories, that should also be build
DIRS = periph $(ATMEGA_COMMON)
DIRS = $(ATMEGA_COMMON)
include $(RIOTBASE)/Makefile.base

6
cpu/atmega2560/Makefile.include
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@ -4,12 +4,6 @@ export CFLAGS += -DCOREIF_NG=1
# tell the build system that the CPU depends on the atmega common files
USEMODULE += atmega_common
# export the peripheral drivers to be linked into the final binary
export USEMODULE += periph
# the atmel port uses uart_stdio
export USEMODULE += uart_stdio
# define path to atmega common module, which is needed for this CPU
export ATMEGA_COMMON = $(RIOTCPU)/atmega_common/

96
cpu/atmega2560/include/atmega2560_regs.h
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@ -1,96 +0,0 @@
/*
* Copyright (C) 2016 Freie Universität Berlin
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup cpu_atmega2560
* @{
*
* @file
* @brief CMSIS style register definitions for the atmega2560
*
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
*/
#ifndef ATMEGA2560_REGS_H
#define ATMEGA2560_REGS_H
#include <avr/io.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief Register types
* @{
*/
#define REG8 volatile uint8_t
#define REG16 volatile uint16_t
/** @} */
/**
* @brief Timer register map
*/
typedef struct {
REG8 CRA; /**< control A */
REG8 CRB; /**< control B */
REG8 CRC; /**< control C */
REG8 reserved; /**< reserved */
REG16 CNT; /**< counter */
REG16 ICR; /**< input capture */
REG16 OCR[3]; /**< output compare */
} mega_timer_t;
/**
* @brief UART register map
*/
typedef struct {
REG8 CSRA; /**< control and status register A */
REG8 CSRB; /**< control and status register B */
REG8 CSRC; /**< control and status register C */
REG8 reserved; /**< reserved */
REG16 BRR; /**< baud rate register */
REG8 DR; /**< data register */
} mega_uart_t;
/**
* @brief Base register address definitions
* @{
*/
#define MEGA_TIMER1_BASE (uint16_t *)(&TCCR1A)
#define MEGA_TIMER3_BASE (uint16_t *)(&TCCR3A)
#define MEGA_TIMER4_BASE (uint16_t *)(&TCCR4A)
#define MEGA_TIMER5_BASE (uint16_t *)(&TCCR5A)
#define MEGA_UART0_BASE ((uint16_t *)(&UCSR0A))
#define MEGA_UART1_BASE ((uint16_t *)(&UCSR1A))
#define MEGA_UART2_BASE ((uint16_t *)(&UCSR2A))
#define MEGA_UART3_BASE ((uint16_t *)(&UCSR3A))
/** @} */
/**
* @brief Peripheral instances
* @{
*/
#define MEGA_TIMER1 ((mega_timer_t *)MEGA_TIMER1_BASE)
#define MEGA_TIMER3 ((mega_timer_t *)MEGA_TIMER3_BASE)
#define MEGA_TIMER4 ((mega_timer_t *)MEGA_TIMER4_BASE)
#define MEGA_TIMER5 ((mega_timer_t *)MEGA_TIMER5_BASE)
#define MEGA_UART0 ((mega_uart_t *)MEGA_UART0_BASE)
#define MEGA_UART1 ((mega_uart_t *)MEGA_UART1_BASE)
#define MEGA_UART2 ((mega_uart_t *)MEGA_UART2_BASE)
#define MEGA_UART3 ((mega_uart_t *)MEGA_UART3_BASE)
/** @} */
#ifdef __cplusplus
}
#endif
#endif /* ATMEGA2560_REGS_H */
/** @} */

2
cpu/atmega2560/include/cpu_conf.h
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@ -20,7 +20,7 @@
#ifndef CPU_CONF_H
#define CPU_CONF_H
#include "atmega2560_regs.h"
#include "atmega_regs_common.h"
#ifdef __cplusplus
extern "C" {

55
cpu/atmega2560/include/periph_cpu.h
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@ -21,15 +21,12 @@
#ifndef PERIPH_CPU_H_
#define PERIPH_CPU_H_
#include "periph_cpu_common.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief Define a CPU specific GPIO pin generator macro
*/
#define GPIO_PIN(x, y) ((x << 4) | y)
/**
* @brief Available ports on the ATmega2560 family
*/
@ -47,54 +44,6 @@ enum {
PORT_L = 10 /**< port L */
};
/**
* @brief SPI mode select macro
*
* The polarity is determined by bit 3 in the configuration register, the phase
* by bit 2.
*/
#define SPI_MODE_SEL(pol, pha) ((pol << 3) | (pha << 2))
/**
* @brief Override the SPI mode values
*
* As the mode is set in bit 3 and 2 of the configuration register, we put the
* correct configuration there
* @{
*/
#define HAVE_SPI_CONF_T
typedef enum {
SPI_CONF_FIRST_RISING = SPI_MODE_SEL(0, 0), /**< mode 0 */
SPI_CONF_SECOND_RISING = SPI_MODE_SEL(0, 1), /**< mode 1 */
SPI_CONF_FIRST_FALLING = SPI_MODE_SEL(1, 0), /**< mode 2 */
SPI_CONF_SECOND_FALLING = SPI_MODE_SEL(1, 1) /**< mode 3 */
} spi_conf_t;
/** @} */
/**
* @brief SPI speed selection macro
*
* We encode the speed in bits 2, 1, and 0, where bit0 and bit1 hold the SPCR
* prescaler bits, while bit2 holds the SPI2X bit.
*/
#define SPI_SPEED_SEL(s2x, pr1, pr0) ((s2x << 2) | (pr1 << 1) | pr0)
/**
* @brief Override SPI speed values
*
* We assume a master clock speed of 16MHz here.
* @{
*/
#define HAVE_SPI_SPEED_T
typedef enum {
SPI_SPEED_100KHZ = SPI_SPEED_SEL(0, 1, 1), /**< 16/128 -> 125KHz */
SPI_SPEED_400KHZ = SPI_SPEED_SEL(1, 1, 0), /**< 16/32 -> 500KHz */
SPI_SPEED_1MHZ = SPI_SPEED_SEL(0, 0, 1), /**< 16/16 -> 1MHz */
SPI_SPEED_5MHZ = SPI_SPEED_SEL(0, 0, 0), /**< 16/4 -> 4MHz */
SPI_SPEED_10MHZ = SPI_SPEED_SEL(1, 0, 0) /**< 16/2 -> 8MHz */
} spi_speed_t;
/** @} */
#ifdef __cplusplus
}
#endif

3
cpu/atmega2560/periph/Makefile
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@ -1,3 +0,0 @@
MODULE = periph
include $(RIOTBASE)/Makefile.base

257
cpu/atmega2560/periph/gpio.c
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@ -1,257 +0,0 @@
/*
* Copyright (C) 2015 HAW Hamburg
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup driver_periph
* @{
*
* @file
* @brief Low-level GPIO driver implementation for ATmega2560
*
* @author René Herthel <rene-herthel@outlook.de>
*
* @}
*/
#include <stdio.h>
#include <avr/interrupt.h>
#include "cpu.h"
#include "periph/gpio.h"
#include "periph_conf.h"
#define GPIO_BASE_PORT_A (0x20)
#define GPIO_OFFSET_PORT_H (0xCB)
#define GPIO_OFFSET_PIN_PORT (0x02)
#define GPIO_OFFSET_PIN_PIN (0x03)
#define GPIO_EXT_INT_NUMOF (8U)
static gpio_isr_ctx_t config[GPIO_EXT_INT_NUMOF];
/**
* @brief Extract the pin number of the given pin
*/
static inline uint8_t _pin_num(gpio_t pin)
{
return (pin & 0x0f);
}
/**
* @brief Extract the port number of the given pin
*/
static inline uint8_t _port_num(gpio_t pin)
{
return (pin >> 4) & 0x0f;
}
/**
* @brief Generate the PORTx address of the give pin.
*/
static inline uint16_t _port_addr(gpio_t pin)
{
uint8_t port_num = _port_num(pin);
uint16_t port_addr = port_num * GPIO_OFFSET_PIN_PIN;
port_addr += GPIO_BASE_PORT_A;
port_addr += GPIO_OFFSET_PIN_PORT;
if (port_num > PORT_G) {
port_addr += GPIO_OFFSET_PORT_H;
}
return port_addr;
}
/**
* @brief Generate the DDRx address of the given pin
*/
static inline uint16_t _ddr_addr(gpio_t pin)
{
return (_port_addr(pin) - 0x01);
}
/**
* @brief Generate the PINx address of the given pin.
*/
static inline uint16_t _pin_addr(gpio_t pin)
{
return (_port_addr(pin) - 0x02);
}
int gpio_init(gpio_t pin, gpio_mode_t mode)
{
switch (mode) {
case GPIO_OUT:
_SFR_MEM8(_ddr_addr(pin)) |= (1 << _pin_num(pin));
break;
case GPIO_IN:
_SFR_MEM8(_ddr_addr(pin)) &= ~(1 << _pin_num(pin));
_SFR_MEM8(_port_addr(pin)) &= ~(1 << _pin_num(pin));
break;
case GPIO_IN_PU:
_SFR_MEM8(_port_addr(pin)) |= (1 << _pin_num(pin));
break;
default:
return -1;
}
return 0;
}
int gpio_init_int(gpio_t pin, gpio_mode_t mode, gpio_flank_t flank,
gpio_cb_t cb, void *arg)
{
uint8_t pin_num = _pin_num(pin);
if ((_port_num(pin) == PORT_D && pin_num > 3)
|| (_port_num(pin) == PORT_E && pin_num < 4)
|| ((mode != GPIO_IN) && (mode != GPIO_IN_PU))) {
return -1;
}
gpio_init(pin, mode);
/* clear global interrupt flag */
cli();
EIMSK |= (1 << pin_num);
/* configure the flank */
switch (flank) {
case GPIO_RISING:
if (pin_num < 4) {
EICRA |= (3 << pin_num * 2);
}
else {
EICRB |= (3 << (pin_num * 2) % 4);
}
break;
case GPIO_FALLING:
if (pin_num < 4) {
EICRA |= (2 << pin_num * 2);
}
else {
EICRB |= (2 << (pin_num * 2) % 4);
}
break;
case GPIO_BOTH:
if (pin_num < 4) {
EICRA |= (1 << pin_num * 2);
}
else {
EICRB |= (1 << (pin_num * 2) % 4);
}
break;
default:
return -1;
};
/* set callback */
config[pin_num].cb = cb;
config[pin_num].arg = arg;
/* set global interrupt flag */
sei();
return 0;
}
void gpio_irq_enable(gpio_t pin)
{
EIMSK |= (1 << _pin_num(pin));
}
void gpio_irq_disable(gpio_t pin)
{
EIMSK &= ~(1 << _pin_num(pin));
}
int gpio_read(gpio_t pin)
{
return (_SFR_MEM8(_pin_addr(pin)) & (1 << _pin_num(pin)));
}
void gpio_set(gpio_t pin)
{
_SFR_MEM8(_port_addr(pin)) |= (1 << _pin_num(pin));
}
void gpio_clear(gpio_t pin)
{
_SFR_MEM8(_port_addr(pin)) &= ~(1 << _pin_num(pin));
}
void gpio_toggle(gpio_t pin)
{
if (gpio_read(pin)) {
gpio_clear(pin);
}
else {
gpio_set(pin);
}
}
void gpio_write(gpio_t pin, int value)
{
if (value) {
gpio_set(pin);
}
else {
gpio_clear(pin);
}
}
static inline void irq_handler(uint8_t pin_num)
{
__enter_isr();
config[pin_num].cb(config[pin_num].arg);
__exit_isr();
}
ISR(INT0_vect, ISR_BLOCK)
{
irq_handler(0); /**< predefined interrupt pin */
}
ISR(INT1_vect, ISR_BLOCK)
{
irq_handler(1); /**< predefined interrupt pin */
}
ISR(INT2_vect, ISR_BLOCK)
{
irq_handler(2); /**< predefined interrupt pin */
}
ISR(INT3_vect, ISR_BLOCK)
{
irq_handler(3); /**< predefined interrupt pin */
}
ISR(INT4_vect, ISR_BLOCK)
{
irq_handler(4); /**< predefined interrupt pin */
}
ISR(INT5_vect, ISR_BLOCK)
{
irq_handler(5); /**< predefined interrupt pin */
}
ISR(INT6_vect, ISR_BLOCK)
{
irq_handler(6); /**< predefined interrupt pin */
}
ISR(INT7_vect, ISR_BLOCK)
{
irq_handler(7); /**< predefined interrupt pin */
}

145
cpu/atmega2560/periph/spi.c
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@ -1,145 +0,0 @@
/*
* Copyright (C) 2015 Daniel Amkaer Sorensen
* 2016 Freie Universität Berlin
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup cpu_atmega2560
* @{
*
* @file
* @brief Low-level SPI driver implementation
*
* @author Daniel Amkaer Sorensen <daniel.amkaer@gmail.com>
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
*
* @}
*/
#include "cpu.h"
#include "mutex.h"
#include "periph/spi.h"
/* guard this file in case no SPI device is defined */
#if SPI_NUMOF
/**
* @brief Extract BR0, BR1 and SPI2X bits from speed value
* @{
*/
#define SPEED_MASK (0x3)
#define S2X_SHIFT (2)
/** @} */
static mutex_t lock = MUTEX_INIT;
int spi_init_master(spi_t dev, spi_conf_t conf, spi_speed_t speed)
{
/* make sure device is valid (there is only one...) */
if (dev != 0) {
return -1;
}
/* the pin configuration for this CPU is fixed:
* - PB3: MISO (configure as input - done automatically)
* - PB2: MOSI (configure as output)
* - PB1: SCK (configure as output)
* - PB0: SS (configure as output, but unused)
*
* The SS pin must be configured as output for the SPI device to work as
* master correctly, though we do not use it for now (as we handle the chip
* select externally for now)
*/
DDRB |= ((1 << DDB2) | (1 << DDB1) | (1 << DDB0));
/* make sure the SPI is not powered off */
PRR0 &= ~(1 << PRSPI);
/* configure as master, with given mode and clock */
SPSR = (speed >> S2X_SHIFT);
SPCR = ((1 << SPE) | (1 << MSTR) | conf | (speed & SPEED_MASK));
/* clear interrupt flag */
(void)SPSR;
(void)SPDR;
return 0;
}
int spi_acquire(spi_t dev)
{
mutex_lock(&lock);
return 0;
}
int spi_release(spi_t dev)
{
mutex_unlock(&lock);
return 0;
}
int spi_init_slave(spi_t dev, spi_conf_t conf, char (*cb)(char data))
{
(void) dev;
(void) conf;
(void) cb;
/* not implemented */
return -1;
}
void spi_transmission_begin(spi_t dev, char reset_val)
{
(void)dev;
(void)reset_val;
/* not implemented */
}
int spi_transfer_byte(spi_t dev, char out, char *in)
{
return spi_transfer_bytes(dev, &out, in, 1);
}
int spi_transfer_bytes(spi_t dev, char *out, char *in, unsigned int length)
{
for (unsigned int i = 0; i < length; i++) {
char tmp = (out) ? out[i] : 0;
SPDR = tmp;
while (!(SPSR & (1 << SPIF))) {}
tmp = SPDR;
if (in) {
in[i] = tmp;
}
}
return (int)length;
}
int spi_transfer_reg(spi_t dev, uint8_t reg, char out, char *in)
{
spi_transfer_bytes(dev, (char *)&reg, NULL, 1);
return spi_transfer_bytes(dev, &out, in, 1);
}
int spi_transfer_regs(spi_t dev, uint8_t reg, char *out, char *in, unsigned int length)
{
spi_transfer_bytes(dev, (char *)&reg, NULL, 1);
return spi_transfer_bytes(dev, out, in, length);
}
void spi_poweron(spi_t dev)
{
SPCR |= (1 << SPE);
}
void spi_poweroff(spi_t dev)
{
SPCR &= ~(1 << SPE);
}
#endif /* SPI_NUMOF */

258
cpu/atmega2560/periph/timer.c
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@ -1,258 +0,0 @@
/*
* Copyright (C) 2014 Freie Universität Berlin, Hinnerk van Bruinehsen
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup driver_periph
* @{
*
* @file
* @brief Low-level timer driver implementation for the ATmega2560 CPU
*
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
* @author Hinnerk van Bruinehsen <h.v.bruinehsen@fu-berlin.de>
*
* @}
*/
#include <avr/interrupt.h>
#include "board.h"
#include "cpu.h"
#include "thread.h"
#include "periph/timer.h"
#include "periph_conf.h"
/**
* @brief All timers have three channels
*/
#define CHANNELS (3)
/**
* @brief We have 5 possible prescaler values
*/
#define PRESCALE_NUMOF (5U)
/**
* @brief Possible prescaler values, encoded as 2 ^ val
*/
static const uint8_t prescalers[] = { 0, 3, 6, 8, 10 };
/**
* @brief Timer state context
*/
typedef struct {
mega_timer_t *dev; /**< timer device */
volatile uint8_t *mask; /**< address of interrupt mask register */
volatile uint8_t *flag; /**< address of interrupt flag register */
timer_cb_t cb; /**< interrupt callback */
void *arg; /**< interrupt callback argument */
uint8_t mode; /**< remember the configured mode */
uint8_t isrs; /**< remember the interrupt state */
} ctx_t;
/**
* @brief Allocate memory for saving the device states
* @{
*/
#if TIMER_NUMOF
static ctx_t ctx[] = {
#ifdef TIMER_0
{ TIMER_0, TIMER_0_MASK, TIMER_0_FLAG, NULL, NULL, 0, 0 },
#endif
#ifdef TIMER_1
{ TIMER_1, TIMER_1_MASK, TIMER_1_FLAG, NULL, NULL, 0, 0 },
#endif
#ifdef TIMER_2
{ TIMER_2, TIMER_2_MASK, TIMER_2_FLAG, NULL, NULL, 0, 0 },
#endif
#ifdef TIMER_3
{ TIMER_3, TIMER_3_MASK, TIMER_3_FLAG, NULL, NULL, 0, 0 },
#endif
};
#else
/* fallback if no timer is configured */
static ctx_t *ctx[] = {{ NULL }};
#endif
/** @} */
/**
* @brief Setup the given timer
*/
int timer_init(tim_t tim, unsigned long freq, timer_cb_t cb, void *arg)
{
uint8_t pre = 0;
/* make sure given device is valid */
if (tim >= TIMER_NUMOF) {
return -1;
}
/* figure out if freq is applicable */
for (; pre < PRESCALE_NUMOF; pre++) {
if ((CLOCK_CORECLOCK >> prescalers[pre]) == freq) {
break;
}
}
if (pre == PRESCALE_NUMOF) {
return -1;
}
/* stop and reset timer */
ctx[tim].dev->CRA = 0;
ctx[tim].dev->CRB = 0;
ctx[tim].dev->CRC = 0;
ctx[tim].dev->CNT = 0;
/* save interrupt context and timer mode */
ctx[tim].cb = cb;
ctx[tim].arg = arg;
ctx[tim].mode = (pre + 1);
/* enable timer with calculated prescaler */
ctx[tim].dev->CRB = (pre + 1);
return 0;
}
int timer_set(tim_t tim, int channel, unsigned int timeout)
{
return timer_set_absolute(tim, channel, timer_read(tim) + timeout);
}
int timer_set_absolute(tim_t tim, int channel, unsigned int value)
{
if (channel >= CHANNELS) {
return -1;
}
ctx[tim].dev->OCR[channel] = (uint16_t)value;
*ctx[tim].flag &= ~(1 << (channel + OCF1A));
*ctx[tim].mask |= (1 << (channel + OCIE1A));
return 0;
}
int timer_clear(tim_t tim, int channel)
{
if (channel >= CHANNELS) {
return -1;
}
*ctx[tim].mask &= ~(1 << (channel + OCIE1A));
return 0;
}
unsigned int timer_read(tim_t tim)
{
return (unsigned int)ctx[tim].dev->CNT;
}
void timer_stop(tim_t tim)
{
ctx[tim].dev->CRB = 0;
}
void timer_start(tim_t tim)
{
ctx[tim].dev->CRB = ctx[tim].mode;
}
void timer_irq_enable(tim_t tim)
{
*ctx[tim].mask = ctx[tim].isrs;
}
void timer_irq_disable(tim_t tim)
{
ctx[tim].isrs = *(ctx[tim].mask);
*ctx[tim].mask = 0;
}
static inline void _isr(int num, int chan)
{
__enter_isr();
*ctx[num].mask &= ~(1 << (chan + OCIE1A));
ctx[num].cb(ctx[num].arg, chan);
if (sched_context_switch_request) {
thread_yield();
}
__exit_isr();
}
#ifdef TIMER_0
ISR(TIMER_0_ISRA, ISR_BLOCK)
{
_isr(0, 0);
}
ISR(TIMER_0_ISRB, ISR_BLOCK)
{
_isr(0, 1);
}
ISR(TIMER_0_ISRC, ISR_BLOCK)
{
_isr(0, 2);
}
#endif /* TIMER_0 */
#ifdef TIMER_1
ISR(TIMER_1_ISRA, ISR_BLOCK)
{
_isr(1, 0);
}
ISR(TIMER_1_ISRB, ISR_BLOCK)
{
_isr(1, 1);
}
ISR(TIMER_1_ISRC, ISR_BLOCK)
{
_isr(1, 2);
}
#endif /* TIMER_1 */
#ifdef TIMER_2
ISR(TIMER_2_ISRA, ISR_BLOCK)
{
_isr(2, 0);
}
ISR(TIMER_2_ISRB, ISR_BLOCK)
{
_isr(2, 1);
}
ISR(TIMER_2_ISRC, ISR_BLOCK)
{
_isr(2, 2);
}
#endif /* TIMER_2 */
#ifdef TIMER_3
ISR(TIMER_3_ISRA, ISR_BLOCK)
{
_isr(2, 0);
}
ISR(TIMER_3_ISRB, ISR_BLOCK)
{
_isr(2, 1);
}
ISR(TIMER_3_ISRC, ISR_BLOCK)
{
_isr(2, 2);
}
#endif /* TIMER_3 */

133
cpu/atmega2560/periph/uart.c
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@ -1,133 +0,0 @@
/*
* Copyright (C) 2014 Freie Universität Berlin, Hinnerk van Bruinehsen
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup driver_periph
* @{
*
* @file
* @brief Low-level UART driver implementation
*
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
* @author Hinnerk van Bruinehsen <h.v.bruinehsen@fu-berlin.de>
*
* @}
*/
#include "cpu.h"
#include "sched.h"
#include "thread.h"
#include "periph/uart.h"
/**
* @brief Configured device map
* @{
*/
#if UART_NUMOF
static mega_uart_t *dev[] = {
#ifdef UART_0
UART_0,
#endif
#ifdef UART_1
UART_1,
#endif
#ifdef UART_2
UART_2,
#endif
#ifdef UART_3
UART_3
#endif
};
#else
/* fallback if no UART is defined */
static const mega_uart_t *dev[] = { NULL };
#endif
/**
* @brief Allocate memory to store the callback functions.
*/
static uart_isr_ctx_t isr_ctx[UART_NUMOF];
int uart_init(uart_t uart, uint32_t baudrate, uart_rx_cb_t rx_cb, void *arg)
{
/* make sure the given device is valid */
if (uart >= UART_NUMOF) {
return -1;
}
/* register interrupt context */
isr_ctx[uart].rx_cb = rx_cb;
isr_ctx[uart].arg = arg;
/* disable and reset UART */
dev[uart]->CSRB = 0;
dev[uart]->CSRA = 0;
/* configure UART to 8N1 mode */
dev[uart]->CSRC = (1 << UCSZ00) | (1 << UCSZ01);
/* set clock divider */
dev[uart]->BRR = CLOCK_CORECLOCK / (16 * baudrate);
/* enable RX and TX and the RX interrupt */
dev[uart]->CSRB = ((1 << RXCIE0) | (1 << RXEN0) | (1 << TXEN0));
return 0;
}
void uart_write(uart_t uart, const uint8_t *data, size_t len)
{
for (size_t i = 0; i < len; i++) {
while (!(dev[uart]->CSRA & (1 << UDRE0)));
dev[uart]->DR = data[i];
}
}
static inline void isr_handler(int num)
{
isr_ctx[num].rx_cb(isr_ctx[num].arg, dev[num]->DR);
if (sched_context_switch_request) {
thread_yield();
}
}
#ifdef UART_0_ISR
ISR(UART_0_ISR, ISR_BLOCK)
{
__enter_isr();
isr_handler(0);
__exit_isr();
}
#endif /* UART_0_ISR */
#ifdef UART_1_ISR
ISR(UART_1_ISR, ISR_BLOCK)
{
__enter_isr();
isr_handler(1);
__exit_isr();
}
#endif /* UART_1_ISR */
#ifdef UART_2_ISR
ISR(UART_2_ISR, ISR_BLOCK)
{
__enter_isr();
isr_handler(2);
__exit_isr();
}
#endif /* UART_2_ISR */
#ifdef UART_3_ISR
ISR(UART_3_ISR, ISR_BLOCK)
{
__enter_isr();
isr_handler(3);
__exit_isr();
}
#endif /* UART_3_ISR */

4
cpu/atmega_common/Makefile
Unescape View File

@ -1,5 +1,5 @@
# define the module that is build
MODULE = atmega_common
# add a list of subdirectories, that should also be build
DIRS = periph
include $(RIOTBASE)/Makefile.base

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