a074364c |
1 | /* |
2 | Copyright 2011 Jun Wako <wakojun@gmail.com> |
3 | |
4 | This program is free software: you can redistribute it and/or modify |
5 | it under the terms of the GNU General Public License as published by |
6 | the Free Software Foundation, either version 2 of the License, or |
7 | (at your option) any later version. |
8 | |
9 | This program is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
12 | GNU General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU General Public License |
15 | along with this program. If not, see <http://www.gnu.org/licenses/>. |
16 | */ |
17 | |
18 | #ifndef TIMER_AVR_H |
19 | #define TIMER_AVR_H 1 |
20 | |
21 | #include <stdint.h> |
22 | |
23 | #ifndef TIMER_PRESCALER |
24 | # if F_CPU > 16000000 |
25 | # define TIMER_PRESCALER 256 |
26 | # elif F_CPU > 2000000 |
27 | # define TIMER_PRESCALER 64 |
28 | # elif F_CPU > 250000 |
29 | # define TIMER_PRESCALER 8 |
30 | # else |
31 | # define TIMER_PRESCALER 1 |
32 | # endif |
33 | #endif |
34 | #define TIMER_RAW_FREQ (F_CPU/TIMER_PRESCALER) |
35 | #define TIMER_RAW TCNT0 |
36 | #define TIMER_RAW_TOP (TIMER_RAW_FREQ/1000) |
37 | |
38 | #if (TIMER_RAW_TOP > 255) |
39 | # error "Timer0 can't count 1ms at this clock freq. Use larger prescaler." |
40 | #endif |
41 | |
42 | #endif |