| 508 |
kaklik |
1 |
/*
|
|
|
2 |
* Copyright (C) 2004 Darren Hutchinson (dbh@gbdt.com.au)
|
|
|
3 |
*
|
|
|
4 |
* This program is free software; you can redistribute it and/or modify
|
|
|
5 |
* it under the terms of the GNU Library General Public License as published by
|
|
|
6 |
* the Free Software Foundation; either version 2 of the License, or (at your
|
|
|
7 |
* option) any later version.
|
|
|
8 |
*
|
|
|
9 |
* This program is distributed in the hope that it will be useful, but
|
|
|
10 |
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
|
|
11 |
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
|
|
|
12 |
* License for more details.
|
|
|
13 |
*
|
|
|
14 |
* You should have received a copy of the GNU Library General Public License
|
|
|
15 |
* along with this software; see the file COPYING. If not, write to
|
|
|
16 |
* the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
|
|
|
17 |
* MA 02111-1307, USA.
|
|
|
18 |
*
|
|
|
19 |
* $Id: pguide.c,v 1.1.1.1 2004/02/22 08:12:42 dbh Exp $
|
|
|
20 |
*/
|
|
|
21 |
|
|
|
22 |
/* This file contains the code that takes inputs from a parallel output
|
|
|
23 |
* guider (such as the SBIG ST-4) and uses them to make guiding
|
|
|
24 |
* adjustments.
|
|
|
25 |
*/
|
|
|
26 |
|
|
|
27 |
#include <avr/io.h>
|
|
|
28 |
#include <avr/interrupt.h>
|
|
|
29 |
#include <inttypes.h>
|
|
|
30 |
|
|
|
31 |
#include "eq6.h"
|
|
|
32 |
#include "combine.h"
|
|
|
33 |
#include "pguide.h"
|
|
|
34 |
|
|
|
35 |
#define GUIDE_BITS (_BV(G_UP) | _BV(G_DN) | _BV(G_RT) | _BV(G_LT))
|
|
|
36 |
|
|
|
37 |
/* This module polls the input bits from the guider, applies some
|
|
|
38 |
* crude debouncing, and then applies the requested speed adjustment.
|
|
|
39 |
*
|
|
|
40 |
* This code assumes that the inputs are active low (i.e. they are connected
|
|
|
41 |
* to a relay or optocoupler connecting the "active" input to ground).
|
|
|
42 |
*
|
|
|
43 |
* The polling rate is generated by a 8-bit timer with /256
|
|
|
44 |
*/
|
|
|
45 |
|
|
|
46 |
/* pguideInit() initializes the timer used to poll the parallel guiding
|
|
|
47 |
* input bits and sets those bit as inputs.
|
|
|
48 |
*
|
|
|
49 |
* Passed:
|
|
|
50 |
* Nothing
|
|
|
51 |
*
|
|
|
52 |
* Returns:
|
|
|
53 |
* Nothing
|
|
|
54 |
*
|
|
|
55 |
*/
|
|
|
56 |
void
|
|
|
57 |
pguideInit(void)
|
|
|
58 |
{
|
|
|
59 |
/* Set guide bits as inputs with pullups */
|
|
|
60 |
GUIDE_DDR &= ~GUIDE_BITS;
|
|
|
61 |
GUIDE_PORT |= GUIDE_BITS;
|
|
|
62 |
|
|
|
63 |
/* Setup timer 2 to generate interrupts for PWM to the selected
|
|
|
64 |
* rate (in CTC mode)
|
|
|
65 |
*/
|
|
|
66 |
OCR2 = (CLK_RATE / GUIDE_RATE / 1024);
|
|
|
67 |
TCCR2 = _BV(WGM21) | _BV(CS22) | _BV(CS20);
|
|
|
68 |
|
|
|
69 |
/* Enable interrupt generation from timer 2 */
|
|
|
70 |
TIMSK |= _BV(OCIE2);
|
|
|
71 |
}
|
|
|
72 |
|
|
|
73 |
/* pguideInt() is called whenever a timer 2 overflow interrupt occurs
|
|
|
74 |
*
|
|
|
75 |
* Passed:
|
|
|
76 |
* Nothing
|
|
|
77 |
*
|
|
|
78 |
* Returns:
|
|
|
79 |
* Nothing
|
|
|
80 |
*/
|
|
|
81 |
SIGNAL(SIG_OUTPUT_COMPARE2)
|
|
|
82 |
{
|
|
|
83 |
uint8_t guideBits;
|
|
|
84 |
|
|
|
85 |
static uint8_t lastState = GUIDE_BITS;
|
|
|
86 |
static uint8_t lastUsed = GUIDE_BITS;
|
|
|
87 |
|
|
|
88 |
/* Get the guide bits */
|
|
|
89 |
guideBits = GUIDE_PIN & GUIDE_BITS;
|
|
|
90 |
|
|
|
91 |
/* See if they're the same as the last set. If they are then we
|
|
|
92 |
* assume that the guide bits are stable
|
|
|
93 |
*/
|
|
|
94 |
if (guideBits != lastState)
|
|
|
95 |
{
|
|
|
96 |
/* Bits are changing */
|
|
|
97 |
lastState = guideBits;
|
|
|
98 |
}
|
|
|
99 |
else if (lastUsed != lastState)
|
|
|
100 |
{
|
|
|
101 |
/* They're stable and different from the last used set, so
|
|
|
102 |
* update the guiding information
|
|
|
103 |
*/
|
|
|
104 |
|
|
|
105 |
if ((guideBits & _BV(G_UP)) == 0)
|
|
|
106 |
rateInput.guideDecRate = SPEED_0_33_X;
|
|
|
107 |
else if ((guideBits & _BV(G_DN)) == 0)
|
|
|
108 |
rateInput.guideDecRate = -SPEED_0_33_X;
|
|
|
109 |
else
|
|
|
110 |
rateInput.guideDecRate = SPEED_0_X;
|
|
|
111 |
|
|
|
112 |
if ((guideBits & _BV(G_RT)) == 0)
|
|
|
113 |
rateInput.guideRaRate = SPEED_0_33_X;
|
|
|
114 |
else if ((guideBits & _BV(G_LT)) == 0)
|
|
|
115 |
rateInput.guideRaRate = -SPEED_0_33_X;
|
|
|
116 |
else
|
|
|
117 |
rateInput.guideRaRate = SPEED_0_X;
|
|
|
118 |
|
|
|
119 |
/* Update the overall rate */
|
|
|
120 |
updateMountSpeed();
|
|
|
121 |
|
|
|
122 |
/* Update the last used state ('cuz we used it) */
|
|
|
123 |
lastUsed = lastState;
|
|
|
124 |
}
|
|
|
125 |
}
|