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
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
|
/*
* spreadspace avr utils
*
*
* Copyright (C) 2014 Christian Pointner <equinox@spreadspace.org>
*
* This file is part of spreadspace avr utils.
*
* spreadspace avr utils is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* any later version.
*
* spreadspace avr utils is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with spreadspace avr utils. If not, see <http://www.gnu.org/licenses/>.
*/
#include <avr/sfr_defs.h>
#include <avr/interrupt.h>
#include "stepper.h"
uint8_t step_table [] =
{
/* full steps */
/* 6, // 0110 */
/* 5, // 0101 */
/* 9, // 1001 */
/* 10, // 1010 */
/* half steps */
2, // 0010
6, // 0110
4, // 0100
5, // 0101
1, // 0001
9, // 1001
8, // 1000
10, // 1010
};
#define STEPPER_PORT PORTF
#define STEPPER_DDR DDRF
#define STEPPER_FIRST_BIT 4
#define STEPPER_ENABLE_A_BIT 0
#define STEPPER_ENABLE_B_BIT 1
#define LENGTH_STEP_TABLE (sizeof(step_table)/sizeof(uint8_t))
#define STEPPER_OUTPUT_BITMASK (~(0xF << STEPPER_FIRST_BIT ))
void stepper_init(void)
{
STEPPER_PORT &= ~(0xF << STEPPER_FIRST_BIT | 1<<STEPPER_ENABLE_A_BIT | 1<<STEPPER_ENABLE_B_BIT);
STEPPER_DDR |= (0xF << STEPPER_FIRST_BIT) | (1<<STEPPER_ENABLE_A_BIT) | (1<<STEPPER_ENABLE_B_BIT);
}
void stepper_start(void)
{
STEPPER_PORT |= (1<<STEPPER_ENABLE_A_BIT) | (1<<STEPPER_ENABLE_B_BIT);
TCCR1A = 0; // prescaler 1:256, WGM = 4 (CTC)
TCCR1B = 1<<WGM12 | 1<<CS12; //
OCR1A = 150;
TCNT1 = 0;
TIMSK1 = 1<<OCIE1A;
}
void stepper_stop(void)
{
STEPPER_PORT &= ~(0xF << STEPPER_FIRST_BIT | 1<<STEPPER_ENABLE_A_BIT | 1<<STEPPER_ENABLE_B_BIT);
TCCR1B = 0; // no clock source
TIMSK1 = 0; // disable timer interrupt
}
static inline void stepper_handle(void)
{
static uint8_t step_idx = 0;
uint8_t stepper_output = step_table[step_idx];
stepper_output <<= STEPPER_FIRST_BIT;
STEPPER_PORT = (STEPPER_PORT & STEPPER_OUTPUT_BITMASK ) | stepper_output;
step_idx++;
step_idx %= LENGTH_STEP_TABLE;
}
ISR(TIMER1_COMPA_vect)
{
stepper_handle();
}
|