blob: 4b72bf76069ed1b702fc185c415f692a0040ff8c (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
|
// AVR serial port code.
//
// Copyright (C) 2016-2018 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU GPLv3 license.
#include <avr/interrupt.h> // USART0_RX_vect
#include "autoconf.h" // CONFIG_SERIAL_BAUD
#include "board/serial_irq.h" // serial_rx_byte
#include "sched.h" // DECL_INIT
// Define serial port registers on AT90USB1286
#if !defined(UCSR0A) && defined(UCSR1A)
#define UCSR0A UCSR1A
#define UCSR0B UCSR1B
#define UCSR0C UCSR1C
#define UBRR0 UBRR1
#define UDR0 UDR1
#define UCSZ01 UCSZ11
#define UCSZ00 UCSZ10
#define U2X0 U2X1
#define RXEN0 RXEN1
#define TXEN0 TXEN1
#define RXCIE0 RXCIE1
#define UDRIE0 UDRIE1
#define USART0_RX_vect USART1_RX_vect
#define USART0_UDRE_vect USART1_UDRE_vect
#endif
// Define serial port registers on atmega168 / atmega328
#if defined(USART_RX_vect)
#define USART0_RX_vect USART_RX_vect
#define USART0_UDRE_vect USART_UDRE_vect
#endif
void
serial_init(void)
{
UCSR0A = CONFIG_SERIAL_BAUD_U2X ? (1<<U2X0) : 0;
uint32_t cm = CONFIG_SERIAL_BAUD_U2X ? 8 : 16;
UBRR0 = DIV_ROUND_CLOSEST(CONFIG_CLOCK_FREQ, cm * CONFIG_SERIAL_BAUD) - 1UL;
UCSR0C = (1<<UCSZ01) | (1<<UCSZ00);
UCSR0B = (1<<RXEN0) | (1<<TXEN0) | (1<<RXCIE0) | (1<<UDRIE0);
}
DECL_INIT(serial_init);
// Rx interrupt - data available to be read.
ISR(USART0_RX_vect)
{
serial_rx_byte(UDR0);
}
// Tx interrupt - data can be written to serial.
ISR(USART0_UDRE_vect)
{
uint8_t data;
int ret = serial_get_tx_byte(&data);
if (ret)
UCSR0B &= ~(1<<UDRIE0);
else
UDR0 = data;
}
// Enable tx interrupts
void
serial_enable_tx_irq(void)
{
UCSR0B |= 1<<UDRIE0;
}
|
