Read a HDD or Compact Flash

[lucky]

Hi all,
I want to read a HDD or Compact Flash with a PIC (18F452). I have looked at all sources I have found but have had trouble understanding them as they are very complex & have not been written in CCS C. Just a step by step of what I need to do in text would be great.

i.e:
1) set CS high
2) set read pin low
3) . . . . .

Thanks in advance for any help. :grin
_________________
Lucky
www.mpic3.com - MPIC3 player project, Forum, Downloads, Online Shop

[Mark]

Are you planning on using the HDD as just a raw medium or the way a PC uses it with a file system? Something like FAT16 or FAT32?

[lucky]

Hello Mark,

To be able to use Fat16 would be nice but for now I just want to control the HDD / CF itself.

If Im not using FAT I would NEED to be able to write as well as read though.
_________________
Lucky
www.mpic3.com - MPIC3 player project, Forum, Downloads, Online Shop

[fpgeh]

I don't have any experience with interfacing to a HD but I have used CompactFlash and I found this article:
http://www.walrus.com/~raphael/pdf/compactflashOnPicArticle.pdf
to be a good start. Also the CompactFlash specification is a free download from http://www.compactflash.org and contains easy to read timing diagrams.

[dvsoft]

hello

i write this source code for test on CF

#include "C:\YA1-LOGGER\YL\Prototype\Main-Board-Test\CompactFlash\Test_cf.h"
#include <stdlib.h>
#include <input.c>

//-----------------------------------------------------------------------------
// Compact flash card Address A0 to A1, WR an RD signals
//
#define CF_A0 PIN_A0
#define CF_A1 PIN_A1
#define CF_A2 PIN_A2
#define CF_RD PIN_E0
#define CF_WR PIN_E1

//-----------------------------------------------------------------------------
// Compact Data bus
//
#byte CF_DATA = 0xF83

//-----------------------------------------------------------------------------
// Compact flash tris data
//
#define CF_DATA_TRIS_IN 0xFF
#define CF_DATA_TRIS_OUT 0x00
#define CF_ADDRESS_TRIS 0x00
#define CF_SIGNAL_TRIS 0x00

//-----------------------------------------------------------------------------
// Use fast io port D,A,E
//
#use fast_io(A)
#use fast_io(D)
#use fast_io(E)

unsigned int16 CF_Signature;
unsigned int16 CF_Maxsector;
unsigned int16 CF_Maxhead;
unsigned int16 CF_Maxcyl;

//-----------------------------------------------------------------------------
void InitPic(void)
{
setup_adc_ports(NO_ANALOGS);
setup_adc(ADC_OFF);
setup_psp(PSP_DISABLED);
setup_spi(FALSE);
setup_wdt(WDT_OFF);
setup_timer_0(RTCC_INTERNAL);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);
setup_timer_3(T3_DISABLED|T3_DIV_BY_1);
}
//-----------------------------------------------------------------------------
void CF_SetAddress(BYTE address)
{
output_bit(CF_A0, bit_test(address, 0));
output_bit(CF_A1, bit_test(address, 1));
output_bit(CF_A2, bit_test(address, 2));
}
//-----------------------------------------------------------------------------
void CF_Init(void)
{
//--- Set data tris
set_tris_d(CF_DATA_TRIS_IN);
//--- Set Address tris
set_tris_a(CF_ADDRESS_TRIS);
//--- Set signal tris
set_tris_e(CF_SIGNAL_TRIS);
}
//-----------------------------------------------------------------------------
int CF_Read()
{
unsigned int Data;
set_tris_d(CF_DATA_TRIS_IN);
//--- strobe read signal and get data
output_low(CF_RD);
Data = CF_DATA;
output_high(CF_RD);
return Data;
}
//-----------------------------------------------------------------------------
void CF_Write(BYTE Data)
{
// set data
set_tris_d(CF_DATA_TRIS_OUT);
CF_DATA = Data;
// Strobe write signal
output_low(CF_WR);
output_high(CF_WR);
}
//-----------------------------------------------------------------------------
void CF_WriteData(BYTE Address,BYTE Data)
{
//--- Set Address
CF_SetAddress(Address);
//--- Write data
CF_Write(Data);
}
//-----------------------------------------------------------------------------
void CF_SkipByte(Byte ByteCount)
{
Byte ByteCnt;
ByteCnt = ByteCount;
do {
output_low(CF_RD);
output_high(CF_RD);
}while (--ByteCount);
}
//-----------------------------------------------------------------------------
BYTE CF_ReadData(BYTE Address)
{
//--- Set Address
CF_SetAddress(Address);
//--- Read Data
return CF_Read();
}
//-----------------------------------------------------------------------------
BOOLEAN CF_Reset(void)
{
BYTE i;
//--- Reset no interrupt
CF_WriteData(6,0x06);
//--- Wait 1s
delay_ms(1000);
//--- End Reset, no interrupt
CF_WriteData(6,0x02);
//--- CF Status register address
CF_SetAddress(7);
//--- Loop wait ready
i = 10;
do {
//--- CF not Busy ? (D7)
if (!bit_test(CF_Read(),7))
//--- Reset Ok
return TRUE;
delay_ms(10);
}while(--i);
return FALSE;
}
//-----------------------------------------------------------------------------
BOOLEAN CF_Indentify(void)
{
//--- Send drive No
CF_WriteData(6,0xA0);
//--- Send Read Status Command
CF_WriteData(7,0xEC);
//--- Wait Busy D7
while(bit_test(CF_Read(),7));
//--- Set Address buffer 0
CF_SetAddress(0x00);
//--- General configuration - signature for the CompactFlash Storage Card
CF_Signature = CF_Read() + (256*CF_Read());
//--- Default number of cylinders
CF_Maxcyl = CF_Read() + (256*CF_Read());
//--- Skip 2 bytes
CF_SkipByte(2);
//--- Default number of heads
CF_Maxhead = CF_Read() + (256*CF_Read());
//--- Skip 4 bytes
CF_SkipByte(4);
//--- Default number of sectors per track
CF_Maxsector = CF_Read() + (256*CF_Read());
//--- Success if dataflash storage signature = 0x848A
return (CF_Signature == 0x848A);
}
//-----------------------------------------------------------------------------
void main()
{
unsigned int8 Add,Value;
//--- Initialisation
InitPic();
//--- Power up delays
delay_ms(200);
//--- Message
printf("Compact flash test\r\n");
CF_Init();
//--- Main loop
while(1) {
if (kbhit()) {
switch (getc()) {
case '0':// Test signal RD = 0
printf("RD = 0\r\n");
output_low(CF_RD);
break;
case '1':// Test signal RD = 1
printf("RD = 1\r\n");
output_high(CF_RD);
break;
case '2':// Test signal wr = 0
printf("WD = 0\r\n");
output_low(CF_WR);
break;
case '3':// Test signal wr = 1
printf("WD = 1\r\n");
output_high(CF_WR);
break;
case 'w':// Test write
printf("Address :");
Add = get_int();
printf(" Value :");
Value = get_int();
CF_SetAddress(Add);
CF_Write(Value);
printf(" OK\r\n");
break;
case 'r':// Test read
printf("Address :");
Add = get_int();
CF_SetAddress(Add);
printf("Read %x\r\n",CF_Read());
break;
case 'a':// Test Set Adresse
printf("Address :");
Add = get_int();
CF_SetAddress(Add);
printf(" Ok\r\n");
break;
case 'd':// Dump after cmd a
printf("Read %x\r\n",CF_Read());
break;
case 'i':// Identify function (only after reset function
printf("Indentify..\r\n");
if (CF_Indentify()) {
printf("CF_Signature :%lu\r\n",CF_Signature);
printf("Nb Sector by track :%lu\r\n",CF_Maxsector);
printf("Nb Head :%lu\r\n",CF_Maxhead);
printf("Nb Cylinder :%lu\r\n",CF_Maxcyl);
}// End IF
else
printf("Compact not ready !!\r\n");
break;
case 'u':// Reset Test
printf("Reset....");
if (CF_Reset())
printf(" Ok\r\n");
else
printf(" No Ok\r\n");
break;
}// End Switch
}// End if
}// End while

}
//-----------------------------------------------------------------------------

[lucky]

dvsoft,

Thank you, this is exactly what I wanted . It all looks so simple too !!

Thanks.
_________________
Lucky
www.mpic3.com - MPIC3 player project, Forum, Downloads, Online Shop

[lucky]

Responce to Private Message:

Hello ljbeng,

I havent had much time to work on this project but I am just getting back into it after a long break. I am able to ID the CF & write & read data to & from the card but I need to do a little tidying before I release the code.

At the moment I have no FAT implementation but I may try to run FAT16 soon.

I will put all of my code so far on my website in the next few days. Then you can go there & download it & all of my supporting documents.

The address is www.Mpic3.com.

Please bear in mind that the site is not yet complete!
_________________
Lucky
www.mpic3.com - MPIC3 player project, Forum, Downloads, Online Shop

[SteveS]

This fellow has PIC code for FAT16 - geared towards reading MP3 files. I have modified the code to run on an 18F6620 and all the basics work.

http://www.walrus.com/~raphael/html/mp3.html

[D. Collin]

Hi all,

Sorry if this is repeated question/answer:

Using the code provided here (highly appreciated) by dvsoft, I can communicate with the CF card, the Identify function returns correct data:

Signature: 33930
Sector by track: 32
Heads: 8
Cylinders: 978

Then I tried to use:

CF_WriteData(5,0); //Cylinder high
CF_WriteData(4,0); //Cylinder Low
CF_WriteData(3,1); //Select sector # 1
CF_WriteData(6,0xA0); //Select Card 0, Head 0
CF_WriteData(2,1); //1 sector to read
CF_WriteData(7,0x20); //Send Read Command

//delay for 1 ms for card to fill card buffer

And then call CF_ReadData(0) 512 times to fill PIC internal buffer with the sector data.

Shouldn�t this fill the buffer with the first sector (boot sector) which is on head 0, cylinder 0, and sector 1? It doesn�t when comparing the first sector with WinHex.

I feel I am doing something wrong here but I am using the exact code provided with the addition of the above code to read sector 0.

Thanx in advance.

D.Collin