| | 1 | /* vim:ts=4 sts=4 et tw=80 |
| | 2 | * |
| | 3 | * fnordlicht firmware |
| | 4 | * |
| | 5 | * for additional information please |
| | 6 | * see http://lochraster.org/fnordlichtmini |
| | 7 | * |
| | 8 | * (c) by Alexander Neumann <alexander@bumpern.de> |
| | 9 | * Lars Noschinski <lars@public.noschinski.de> |
| | 10 | * |
| | 11 | * This program is free software: you can redistribute it and/or modify it |
| | 12 | * under the terms of the GNU General Public License version 3 as published by |
| | 13 | * the Free Software Foundation. |
| | 14 | * |
| | 15 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| | 16 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| | 17 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| | 18 | * more details. |
| | 19 | * |
| | 20 | * You should have received a copy of the GNU General Public License along with |
| | 21 | * this program. If not, see <http://www.gnu.org/licenses/>. |
| | 22 | */ |
| | 23 | |
| | 24 | #include "globals.h" |
| | 25 | |
| | 26 | #if CONFIG_SERIAL |
| | 27 | |
| | 28 | #include "../common/io.h" |
| | 29 | #include <avr/interrupt.h> |
| | 30 | |
| | 31 | #include "globals.h" |
| | 32 | #include "../common/common.h" |
| | 33 | #include "fifo.h" |
| | 34 | #include "uart.h" |
| | 35 | |
| | 36 | /* define uart mode (8N1) */ |
| | 37 | #if defined(__AVR_ATmega8__) |
| | 38 | /* in atmega8, we need a special switching bit |
| | 39 | * for addressing UCSRC */ |
| | 40 | #define UART_UCSRC _BV(URSEL) | _BV(UCSZ0) | _BV(UCSZ1) |
| | 41 | |
| | 42 | #elif defined(__AVR_ATmega88__) || defined(__AVR_ATmega168__) |
| | 43 | /* in atmega88, this isn't needed any more */ |
| | 44 | #define UART_UCSRC _BV(_UCSZ0_UART0) | _BV(_UCSZ1_UART0) |
| | 45 | #endif |
| | 46 | |
| | 47 | /* global variables */ |
| | 48 | volatile struct global_uart_t global_uart; |
| | 49 | |
| | 50 | /** output one character */ |
| | 51 | void uart_putc(uint8_t data) |
| | 52 | { |
| | 53 | /* store data */ |
| | 54 | fifo_enqueue((fifo_t *)&global_uart.tx, data); |
| | 55 | |
| | 56 | /* enable interrupt */ |
| | 57 | _UCSRB_UART0 |= _BV(_UDRIE_UART0); |
| | 58 | } |
| | 59 | |
| | 60 | /** init the hardware uart */ |
| | 61 | void uart_init(void) |
| | 62 | { |
| | 63 | #define BAUD CONFIG_SERIAL_BAUDRATE |
| | 64 | #include <util/setbaud.h> |
| | 65 | |
| | 66 | /* set baud rate */ |
| | 67 | _UBRRH_UART0 = UBRRH_VALUE; |
| | 68 | _UBRRL_UART0 = UBRRL_VALUE; |
| | 69 | |
| | 70 | #if USE_2X |
| | 71 | _UCSRA_UART0 |= (1 << _U2X_UART0); |
| | 72 | #endif |
| | 73 | |
| | 74 | /* set mode */ |
| | 75 | _UCSRC_UART0 = UART_UCSRC; |
| | 76 | |
| | 77 | /* enable transmitter, receiver and receiver complete interrupt */ |
| | 78 | _UCSRB_UART0 = _BV(_TXEN_UART0) | _BV(_RXEN_UART0) | _BV(_RXCIE_UART0); |
| | 79 | |
| | 80 | /* init fifos */ |
| | 81 | fifo_init((fifo_t *)&global_uart.rx); |
| | 82 | fifo_init((fifo_t *)&global_uart.tx); |
| | 83 | } |
| | 84 | |
| | 85 | |
| | 86 | /** interrupts*/ |
| | 87 | |
| | 88 | /** uart receive interrupt */ |
| | 89 | ISR(_SIG_UART_RECV_UART0) |
| | 90 | { |
| | 91 | |
| | 92 | /* store received data */ |
| | 93 | fifo_enqueue((fifo_t *)&global_uart.rx, _UDR_UART0); |
| | 94 | |
| | 95 | } |
| | 96 | |
| | 97 | /** uart data register empty interrupt */ |
| | 98 | ISR(_SIG_UART_DATA_UART0) |
| | 99 | { |
| | 100 | |
| | 101 | /* load next byte to transfer */ |
| | 102 | _UDR_UART0 = fifo_dequeue((fifo_t *)&global_uart.tx); |
| | 103 | |
| | 104 | /* check if this interrupt is still needed */ |
| | 105 | if ( fifo_fill((fifo_t *)&global_uart.tx) == 0) { |
| | 106 | /* disable this interrupt */ |
| | 107 | _UCSRB_UART0 &= ~_BV(_UDRIE_UART0); |
| | 108 | } |
| | 109 | |
| | 110 | } |
| | 111 | |
| | 112 | |
| | 113 | #endif |
projects / fnordlicht-mini / blame_incremental