2 Copyright 2011 Jun Wako <wakojun@gmail.com>
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.
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.
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/>.
23 #ifndef TIMER_PRESCALER
25 # define TIMER_PRESCALER 256
26 # elif F_CPU > 2000000
27 # define TIMER_PRESCALER 64
29 # define TIMER_PRESCALER 8
31 # define TIMER_PRESCALER 1
34 #define TIMER_RAW_FREQ (F_CPU/TIMER_PRESCALER)
35 #define TIMER_RAW TCNT0
36 #define TIMER_RAW_TOP (TIMER_RAW_FREQ/1000)
38 #if (TIMER_RAW_TOP > 255)
39 # error "Timer0 can't count 1ms at this clock freq. Use larger prescaler."