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/* -*- c++ -*- */
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/*
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* Copyright 2003 Free Software Foundation, Inc.
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*
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* This file is part of GNU Radio
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*
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* GNU Radio is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 3, or (at your option)
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* any later version.
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*
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* GNU Radio is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with GNU Radio; see the file COPYING. If not, write to
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* the Free Software Foundation, Inc., 51 Franklin Street,
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* Boston, MA 02110-1301, USA.
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*/
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/************************************************************************/
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/** \file timer.c
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************************************************************************/
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#include "timer.h"
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#include "fx2regs.h"
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#include "isr.h"
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/**
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* Arrange to have isr_tick_handler called at 100 Hz.
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*
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* The cpu clock is running at 48e6. The input to the timer
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* is 48e6 / 12 = 4e6.
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*
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* We arrange to have the timer overflow every 40000 clocks == 100 Hz
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*/
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#define RELOAD_VALUE ((unsigned short) -40000)
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void
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hook_timer_tick (unsigned short isr_tick_handler)
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{
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ET2 = 0; /* disable timer 2 interrupts */
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hook_sv (SV_TIMER_2, isr_tick_handler);
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RCAP2H = RELOAD_VALUE >> 8; /* setup the auto reload value */
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RCAP2L = RELOAD_VALUE;
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T2CON = 0x04; /* interrupt on overflow; reload; run */
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ET2 = 1; /* enable timer 2 interrupts */
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}
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