From 730ec2b971458a86c7a2e90901159eaf7b57601d Mon Sep 17 00:00:00 2001 From: Nicolas Schodet Date: Thu, 31 Jan 2008 01:07:51 +0100 Subject: * digital/asserv/src/asserv: - added external counter support. --- digital/asserv/src/asserv/counter_tcc.avr.c | 179 ++++++++++++++++++++++++++++ 1 file changed, 179 insertions(+) create mode 100644 digital/asserv/src/asserv/counter_tcc.avr.c (limited to 'digital/asserv/src/asserv/counter_tcc.avr.c') diff --git a/digital/asserv/src/asserv/counter_tcc.avr.c b/digital/asserv/src/asserv/counter_tcc.avr.c new file mode 100644 index 00000000..5ce4058c --- /dev/null +++ b/digital/asserv/src/asserv/counter_tcc.avr.c @@ -0,0 +1,179 @@ +/* counter_tcc.avr.c - Internal counter support. */ +/* asserv - Position & speed motor control on AVR. {{{ + * + * Copyright (C) 2005 Nicolas Schodet + * + * Robot APB Team/Efrei 2006. + * Web: http://assos.efrei.fr/robot/ + * Email: robot AT efrei DOT fr + * + * This program 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 2 of the License, or + * (at your option) any later version. + * + * This program 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 this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * }}} */ + +/** + * This file add support for an AVR internal counter. This uses one TCC + * hardware per counter, and an external circuitry to compute rotation + * direction. + */ + +/** Define to 1 to reverse the left counter. */ +#define COUNTER_REVERSE_LEFT 0 +/** Define to 1 to reverse the right counter. */ +#define COUNTER_REVERSE_RIGHT 0 + +/** Forward and reverse counter values. */ +static uint8_t counter_left_frw, counter_left_rev, + counter_right_frw, counter_right_rev; +/** Last TCNT values. */ +static uint8_t counter_left_old, counter_right_old; +/** Overall counter values. */ +static uint16_t counter_left, counter_right; +/** Counter differences since last update. + * Maximum of 9 significant bits, sign included. */ +static int16_t counter_left_diff, counter_right_diff; + +/* +AutoDec */ + +/** Initialize the counters. */ +static inline void +counter_init (void); + +/** Update overall counter values and compute diffs. */ +static inline void +counter_update (void); + +/** Restart counting. */ +static inline void +counter_restart (void); + +/* -AutoDec */ + +/** Initialize the counters. */ +static inline void +counter_init (void) +{ + /* Left counter. */ + /* External, rising edge. */ + TCCR2 = regv (FOC2, WGM20, COM21, COM20, WGM21, CS22, CS21, CS20, + 0, 0, 0, 0, 0, 1, 1, 1); + /* Right counter. */ + /* Normal counter. */ + TCCR3A = 0; + /* External, rising edge. */ + TCCR3B = regv (ICNC3, ICES3, 5, WGM33, WGM32, CS32, CS31, CS30, + 0, 0, 0, 0, 0, 1, 1, 1); + /* Begin with safe values. */ + counter_restart (); + /* Interrupts for direction. */ + EICRB = 0x05; + EIFR = _BV (4) | _BV (5); + EIMSK = _BV (4) | _BV (5); +} + +/** Left direction change. */ +SIGNAL (SIG_INTERRUPT4) +{ + uint8_t c; + c = TCNT2; + if (PINE & _BV (4)) + { + counter_left_rev += c - counter_left_old; + GREEN_LED (!COUNTER_REVERSE_LEFT); + } + else + { + counter_left_frw += c - counter_left_old; + GREEN_LED (COUNTER_REVERSE_LEFT); + } + counter_left_old = c; +} + +/** Right direction change. */ +SIGNAL (SIG_INTERRUPT5) +{ + uint8_t c; + c = TCNT3L; + if (PINE & _BV (5)) + { + counter_right_rev += c - counter_right_old; + RED_LED (!COUNTER_REVERSE_RIGHT); + } + else + { + counter_right_frw += c - counter_right_old; + RED_LED (COUNTER_REVERSE_RIGHT); + } + counter_right_old = c; +} + +/** Update overall counter values and compute diffs. */ +static inline void +counter_update (void) +{ + uint8_t c; + /* Disable ints. */ + EIMSK &= ~(_BV (4) | _BV (5)); + /* Read left counter. */ + c = TCNT2; + if (PINE & _BV (4)) + counter_left_frw += c - counter_left_old; + else + counter_left_rev += c - counter_left_old; + counter_left_old = c; + /* Read right counter. */ + c = TCNT3L; + if (PINE & _BV (5)) + counter_right_frw += c - counter_right_old; + else + counter_right_rev += c - counter_right_old; + counter_right_old = c; + /* Update counter values and diffs. */ +#if COUNTER_REVERSE_LEFT == 0 + counter_left_diff = counter_left_frw; + counter_left_diff -= counter_left_rev; +#else + counter_left_diff = counter_left_rev; + counter_left_diff -= counter_left_frw; +#endif + counter_left_frw = 0; + counter_left_rev = 0; + counter_left += counter_left_diff; +#if COUNTER_REVERSE_RIGHT == 0 + counter_right_diff = counter_right_frw; + counter_right_diff -= counter_right_rev; +#else + counter_right_diff = counter_right_rev; + counter_right_diff -= counter_right_frw; +#endif + counter_right_frw = 0; + counter_right_rev = 0; + counter_right += counter_right_diff; + /* Enable ints. */ + EIMSK |= _BV (4) | _BV (5); +} + +/** Restart counting. */ +static inline void +counter_restart (void) +{ + counter_left_frw = 0; + counter_left_rev = 0; + counter_left_old = TCNT2; + counter_right_frw = 0; + counter_right_rev = 0; + counter_right_old = TCNT3L; +} + -- cgit v1.2.3