Project

General

Profile

Download (3.09 KB) Statistics
| Branch: | Tag: | Revision:
1 633c646a henryk
//*----------------------------------------------------------------------------
2
//*         ATMEL Microcontroller Software Support  -  ROUSSET  -
3
//*----------------------------------------------------------------------------
4
//* The software is delivered "AS IS" without warranty or condition of any
5
//* kind, either express, implied or statutory. This includes without
6
//* limitation any warranty or condition with respect to merchantability or
7
//* fitness for any particular purpose, or against the infringements of
8
//* intellectual property rights of others.
9
//*----------------------------------------------------------------------------
10
//* File Name           : Cstartup_SAM7.c
11 13be0cd2 henryk
//* Object              : Low level initializations written in C for IAR
12
//*                       tools
13
//* 1.0   08/Sep/04 JPP : Creation
14
//* 1.10  10/Sep/04 JPP : Update AT91C_CKGR_PLLCOUNT filed
15 633c646a henryk
//*----------------------------------------------------------------------------
16
17 13be0cd2 henryk
18 633c646a henryk
// Include the board file description
19
#include <board.h>
20 062f55ca henryk
// For memcpy
21
#include <string.h>
22 633c646a henryk
23
//*----------------------------------------------------------------------------
24
//* \fn    AT91F_LowLevelInit
25
//* \brief This function performs very low level HW initialization
26
//*        this function can be use a Stack, depending the compilation
27
//*        optimization mode
28
//*----------------------------------------------------------------------------
29 13be0cd2 henryk
void AT91F_LowLevelInit (void)
30 633c646a henryk
{
31 13be0cd2 henryk
    AT91PS_PMC pPMC = AT91C_BASE_PMC;
32
33
    //* Set flash wait state
34
    //  Single Cycle Access at Up to 30 MHz, or 40
35
    //  if MCK = 47923200 I have 50 Cycle for 1 useconde ( flied MC_FMR->FMCN
36
    AT91C_BASE_MC->MC_FMR = ((AT91C_MC_FMCN) & (75 << 16)) | AT91C_MC_FWS_1FWS;
37 633c646a henryk
38 13be0cd2 henryk
    //* Watchdog Enable
39 16d42d5f henryk
    AT91C_BASE_WDTC->WDTC_WDMR = (0x180 << 16) | AT91C_WDTC_WDRSTEN | 0x180;
40 5cc0ed49 henryk
    //AT91C_BASE_WDTC->WDTC_WDMR = 0x8000;
41 633c646a henryk
42 13be0cd2 henryk
    //* Set MCK at 47 923 200
43
    // 1 Enabling the Main Oscillator:
44
    // SCK = 1/32768 = 30.51 uSeconde
45
    // Start up time = 8 * 6 / SCK = 56 * 30.51 = 1,46484375 ms
46
    pPMC->PMC_MOR = (((AT91C_CKGR_OSCOUNT & (0x06 << 8)) | AT91C_CKGR_MOSCEN));
47
    // Wait the startup time
48 633c646a henryk
49 13be0cd2 henryk
    while (!(pPMC->PMC_SR & AT91C_PMC_MOSCS));
50
    // 2 Checking the Main Oscillator Frequency (Optional)
51
    // 3 Setting PLL and divider:
52
    // - div by 5 Fin = 3,6864 =(18,432 / 5)
53
    // - Mul 25+1: Fout =   95,8464 =(3,6864 *26)
54
    // for 96 MHz the erroe is 0.16%
55
    //eld out NOT USED = 0 Fi
56
    pPMC->PMC_PLLR = ((AT91C_CKGR_DIV & 5) |
57
		     (AT91C_CKGR_PLLCOUNT & (28 << 8)) |
58
		     (AT91C_CKGR_MUL & (25 << 16)));
59 633c646a henryk
60 13be0cd2 henryk
    // Wait the startup time
61
    while (!(pPMC->PMC_SR & AT91C_PMC_LOCK));
62
    
63
    // 4. Selection of Master Clock and Processor Clock
64
    // select the PLL clock divided by 2
65
    pPMC->PMC_MCKR = AT91C_PMC_PRES_CLK_2;
66
    while (!(pPMC->PMC_SR & AT91C_PMC_MCKRDY));
67 633c646a henryk
68 13be0cd2 henryk
    pPMC->PMC_MCKR |= AT91C_PMC_CSS_PLL_CLK;
69
    while (!(pPMC->PMC_SR & AT91C_PMC_MCKRDY));
70 616746c2 henryk
    
71 d88d1207 henryk
    /* Copy first 0x200 bytes (IRQ vector table and FIQ) to RAM */
72
    memcpy((void*)0x00200000, (void*)0x00100000, 0x200);
73 616746c2 henryk
    /* Perform remap FIXME doesn't work*/
74
    // AT91C_BASE_MC->MC_RCR = AT91C_MC_RCB;
75 633c646a henryk
}
Add picture from clipboard (Maximum size: 48.8 MB)