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Diffstat (limited to 'firmware/target/coldfire/mpio/hd200/adc-hd200.c')
-rw-r--r--firmware/target/coldfire/mpio/hd200/adc-hd200.c84
1 files changed, 84 insertions, 0 deletions
diff --git a/firmware/target/coldfire/mpio/hd200/adc-hd200.c b/firmware/target/coldfire/mpio/hd200/adc-hd200.c
new file mode 100644
index 0000000000..8bf96436bf
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+++ b/firmware/target/coldfire/mpio/hd200/adc-hd200.c
@@ -0,0 +1,84 @@
1/***************************************************************************
2 * __________ __ ___.
3 * Open \______ \ ____ ____ | | _\_ |__ _______ ___
4 * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
5 * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
6 * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
7 * \/ \/ \/ \/ \/
8 * $Id:$
9 *
10 * Copyright (C) 2010 Marcin Bukat
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version 2
15 * of the License, or (at your option) any later version.
16 *
17 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
18 * KIND, either express or implied.
19 *
20 ****************************************************************************/
21
22#include "config.h"
23#include "cpu.h"
24#include "system.h"
25#include "kernel.h"
26#include "thread.h"
27#include "adc.h"
28
29volatile unsigned short adc_data[NUM_ADC_CHANNELS] IBSS_ATTR;
30
31/* Reading takes 4096 adclk ticks
32 * We do read one channel at once
33 *
34 * state FCPU Fbus Fadc bus/Fadc Fchannelread
35 * default 11.2896 MHz 5.6448 MHz 5.6448 MHz 2 172.2656 Hz
36 * normal 45.1584 MHz 22.5792 MHz 2.8224 MHz 8 172.2656 Hz
37 * max 124.1856 MHz 62.0928 MHz 1.9404 MHz 32 118.4326 Hz
38 */
39
40void ADC(void) __attribute__ ((interrupt_handler,section(".icode")));
41void ADC(void)
42{
43 static unsigned char channel;
44 /* read current value */
45 adc_data[(channel & 0x03)] = ADVALUE;
46
47 /* switch channel
48 *
49 * set source remark
50 * ADCONFIG is 16bit wide so we have to shift data by 16bits left
51 * thats why we shift <<24 instead of <<8
52 */
53
54 channel++;
55
56 and_l(~(3<<24),&ADCONFIG);
57 or_l( (((channel & 0x03) << 8 )|(1<<7))<<16, &ADCONFIG);
58
59}
60
61unsigned short adc_scan(int channel)
62{
63 /* maybe we can drop &0x03 part */
64 return adc_data[(channel&0x03)];
65}
66
67void adc_init(void)
68{
69 /* GPIO38 GPIO39 */
70 and_l(~((1<<6)|(1<<7)), &GPIO1_FUNCTION);
71
72 /* ADOUT_SEL = 01
73 * SOURCE SELECT = 000
74 * CLEAR INTERRUPT FLAG
75 * ENABLE INTERRUPT = 1
76 * ADOUT_DRIVE = 00
77 * ADCLK_SEL = 011 (busclk/8)
78 */
79
80 ADCONFIG = (1<<10)|(1<<7)|(1<<6)|(1<<1)|(1<<0);
81
82 /* ADC interrupt level 4.0 */
83 or_l((4<<28), &INTPRI8);
84}