1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
|
/*
ChibiOS/RT - Copyright (C) 2006-2007 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT 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 3 of the License, or
(at your option) any later version.
ChibiOS/RT 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, see <http://www.gnu.org/licenses/>.
*/
#include <ch.h>
#include "lpc214x.h"
#include "lpc214x_ssp.h"
#include "mmcsd.h"
static EventSource MMCInsertEventSource;
void MMCInit(void) {
chEvtInit(&MMCInsertEventSource);
}
/*
* Initializes a card after the power up by selecting the SPI mode.
*/
BOOL mmcInit(void) {
/*
* Starting initialization with slow clock mode.
*/
SetSSP(254, CR0_DSS8BIT | CR0_FRFSPI | CR0_CLOCKRATE(0), 0);
/*
* SPI mode selection.
*/
sspRW(NULL, NULL, 16); /* 128 clock pulses without ~CS asserted. */
int i = 0;
while (TRUE) {
chThdSleep(10);
if (mmcSendCommand(0, 0) == 0x01)
break;
if (++i >= CMD0_RETRY)
return TRUE;
}
/*
* Initialization.
*/
i = 0;
while (TRUE) {
BYTE8 b;
chThdSleep(10);
b = mmcSendCommand(0, 0);
if (b == 0x00)
break;
if (b != 0x01)
return TRUE;
if (++i >= CMD1_RETRY)
return TRUE;
}
/*
* Full speed.
*/
SetSSP(2, CR0_DSS8BIT | CR0_FRFSPI | CR0_CLOCKRATE(0), 0);
return FALSE;
}
/*
* Sends a simple command and returns a R1-type response.
*/
BYTE8 mmcSendCommand(BYTE8 cmd, ULONG32 arg) {
BYTE8 buf[6];
buf[0] = 0x40 | cmd;
buf[1] = arg >> 24;
buf[2] = arg >> 16;
buf[3] = arg >> 8;
buf[4] = arg;
buf[5] = 0x95; /* Valid for CMD0 ingnored by other commands. */
sspAcquireBus();
sspRW(NULL, buf, 6);
sspRW(buf, NULL, 1);
sspReleaseBus();
return buf[0];
}
|
