Rev 761 | Rev 902 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
471 | cascade | 1 | /**************************************************************************** |
728 | cascade | 2 | * Copyright (C) 2009-2010 by Claas Anders "CaScAdE" Rathje * |
471 | cascade | 3 | * admiralcascade@gmail.com * |
4 | * Project-URL: http://www.mylifesucks.de/oss/c-osd/ * |
||
5 | * * |
||
6 | * This program is free software; you can redistribute it and/or modify * |
||
7 | * it under the terms of the GNU General Public License as published by * |
||
8 | * the Free Software Foundation; either version 2 of the License. * |
||
9 | * * |
||
10 | * This program is distributed in the hope that it will be useful, * |
||
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of * |
||
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * |
||
13 | * GNU General Public License for more details. * |
||
14 | * * |
||
15 | * You should have received a copy of the GNU General Public License * |
||
16 | * along with this program; if not, write to the * |
||
17 | * Free Software Foundation, Inc., * |
||
18 | * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * |
||
19 | ****************************************************************************/ |
||
20 | |||
800 | - | 21 | #include "main.h" |
471 | cascade | 22 | #include <avr/io.h> |
23 | #include <avr/interrupt.h> |
||
24 | #include "spi.h" |
||
25 | |||
514 | cascade | 26 | #if !(ALLCHARSDEBUG|(WRITECHARS != -1)) |
27 | |||
471 | cascade | 28 | volatile uint16_t icnt = 0; |
507 | cascade | 29 | volatile uint8_t request_count = 0; |
471 | cascade | 30 | volatile uint8_t spi_ready = 1; |
507 | cascade | 31 | volatile union SPI_buffer_t SPI_buffer; |
32 | int16_t ampere = 0, max_ampere = 0, s_volt; |
||
471 | cascade | 33 | int32_t ampere_wasted = 0; |
34 | |||
35 | #define INT0_HIGH PORTD |= (1 << PD2); |
||
36 | #define INT0_LOW PORTD &= ~(1 << PD2); |
||
37 | |||
38 | /** |
||
39 | * init the SPI as master |
||
40 | */ |
||
41 | void SpiMasterInit(void) { |
||
42 | volatile char IOReg; |
||
43 | // set PB4(/SS), PB5(MOSI), PB7(SCK) as output |
||
44 | DDRB = (1 << PB4) | (1 << PB5) | (1 << PB7); |
||
45 | PORTB |= (1 << PB4); // pullup SS |
||
46 | // enable SPI Interrupt and SPI in Master Mode with SCK = CK/128 |
||
47 | SPCR = (1 << SPIE) | (1 << SPE) | (1 << MSTR) | (1 << SPR0) | (1 << SPR1); |
||
48 | IOReg = SPSR; // clear SPIF bit in SPSR |
||
49 | IOReg = SPDR; |
||
50 | //sei(); // we do it later |
||
51 | } |
||
52 | |||
53 | /** |
||
54 | * SPI interrupt handler |
||
55 | */ |
||
56 | ISR(SPI_STC_vect) { |
||
761 | - | 57 | if (request_count == 0) { |
58 | SPI_buffer.buffer.chk = SPDR; // firs char received is check byte from last transfer |
||
59 | } else { |
||
60 | SPI_buffer.buffer.c[request_count - 1] = SPDR; // safe received byte to buffer |
||
61 | } |
||
62 | request_count++; |
||
507 | cascade | 63 | if (--icnt) { |
471 | cascade | 64 | //SPDR = *iptr; // send next byte |
65 | spi_ready = 1; // we _should_ send later because the slave needs more time |
||
66 | } else { |
||
67 | SPCR &= ~_BV(SPIE); // deactivate interrupt |
||
68 | INT0_HIGH // transfer is done, slave does not need to listen |
||
69 | } |
||
70 | } |
||
71 | |||
72 | /** |
||
73 | * check if SPI transfer is still busy |
||
74 | */ |
||
75 | int TransferIsBusy(void) { |
||
76 | return SPCR & _BV(SPIE); |
||
77 | } |
||
78 | |||
79 | /** |
||
507 | cascade | 80 | * start a new transfer with length <len> |
471 | cascade | 81 | */ |
507 | cascade | 82 | void StartTransfer(uint16_t len) { |
471 | cascade | 83 | INT0_LOW // /SS LOW ^= SS HIGH ^= slave should listen |
84 | |||
761 | - | 85 | // this is a new request |
86 | request_count = 0; |
||
507 | cascade | 87 | |
471 | cascade | 88 | // set up pointer and length for interrupt handler |
89 | icnt = len; |
||
90 | |||
91 | SPCR |= _BV(SPIE); // enable spi interrupt |
||
761 | - | 92 | SPDR = 'A'; // start transfer by first command char |
471 | cascade | 93 | } |
507 | cascade | 94 | |
95 | /** |
||
96 | * send next command through spi |
||
97 | */ |
||
98 | void spi_send_next() { |
||
761 | - | 99 | SPDR = 'A' + request_count; |
507 | cascade | 100 | } |
514 | cascade | 101 | |
102 | #endif |