MicroSD Cards and SDFS

[rsocor01]

Hi,

I finally got the parts that I needed and started playing with SDFS. Since I'm running my 18F4550 at 3.3V I connected all the MicroSD card pins directly to the PIC. I did not install the 10k resistors since my configuration is a little bit different. Do I need to use these 10K resistors?

I ran the SDTEST.BAS and it worked. It created a file TEST1.TXT with the text "ABC". I could see the file in my cell phone that runs Windows Mobile 6.1. Now, I can't read this card in my Windows XP PC. Somehow, XP does not like FAT16 format in the SD cards. How do you read your SD files in your computer? Is there any work around for this? I don't want to install Win98 in one of my old computers just for this .

Robert

[Normnet]

Now, I can't read this card in my Windows XP PC. Somehow, XP does not like FAT16 format in the SD cards. How do you read your SD files in your computer? Is there any work around for this? I don't want to install Win98 in one of my old computers just for this .

Robert

Try formatting the card with XP using right click on SD drive > format > file system FAT(FAT16).
Be sure you have the correct drive or data loss will occur.

Norm

[Normnet]

Hi,

I finally got the parts that I needed and started playing with SDFS. Since I'm running my 18F4550 at 3.3V I connected all the MicroSD card pins directly to the PIC. I did not install the 10k resistors since my configuration is a little bit different. Do I need to use these 10K resistors?
Robert

I haven't seen the wiring diagram but a 10k resistor would only be required for a 5 volt PIC to
pull up the PIC in-data line as well as others to split the PIC 5 volt lines to SD 3.3 volts.

Norm

[mackrackit]

Running at 3.3 volts I still pull up pins 8 and 9 on the full size SD cards, the remainder I run straight.

Norn is correct about the formatting. I read my FAT16 cards on XP, Vista, Vista 7, and Linux. No problems.

[rsocor01]

Hi,

Thank you guys for your help. Yes, Norm is correct about the formatting of the MicroSD card. It works .

Running at 3.3 volts I still pull up pins 8 and 9 on the full size SD cards, the remainder I run straight.

The breakout board that I got from sparkfun.com doesn't have the connection for the NC pad. Maybe, the resistor at NC is not necessary after all .

http://www.sparkfun.com/commerce/pro...roducts_id=544


Now, I have a question about SDTEST.BAS. The code to write to the card is

' Write to file
	FAT_src[0] = "A"
	FAT_src[1] = "B"
	FAT_src[2] = "C"
	FAT_count = 3
	Gosub FSfwrite
	Serout2 PORTC.6, 84, [ "Write ", Dec FAT_error, $d, $a]
	If (FAT_error != 0) Then Stop

This code will write "ABC" to the card

ABC

But, for data logging I need the entries in diferent lines

A
B
C

Can you do that with SDFS? Thank you for your help.

Robert

[mackrackit]

Maybe the pull-ups on pins 8 and 9 are not needed... Old habits are hard to break.

' Write to file
        FAT_src[0] = "A"
        FAT_src[1] = $d
        FAT_src[2] = $a
        FAT_src[3] = "B"
        FAT_src[4] = $d
        FAT_src[5] = $a
        FAT_src[6] = "C"
        FAT_src[7] = $d
        FAT_src[8] = $a
     FAT_src[9] = $d
     FAT_src[10] = $a 
        FAT_count = 11
    Gosub FSfwrite
    Serout2 PORTC.6, 84, [ "Write ", Dec FAT_error, $d, $a]
    If (FAT_error != 0) Then Stop

[rsocor01]

mackrackit,

Very nice. It works!! This is not in the readme.txt file. How do you know these things? Just kidding.


Now, I have another problem when trying to combine USB and SDFS. I'm not sure if I should open another thread for this problem.

When using USB with PBPL you get the next errors

ERROR: Macro USBINIT? not found in macro file.
ERROR: Macro USBSERVICE? not found in macro file.
ERROR: Macro USBIN?CBBL not found in macro file.
ERROR: Macro USBOUT?CBBL not found in macro file.

The fix for this problem is to include the 18F4550.bal file and the project files in the same directory. This solution was given by Mister_E in the next thread

http://www.picbasic.co.uk/forum/show...=macro+usbinit

Now, if I want to combine USB and SDFS I would have to use the file 18F4550.bal. But if I compile my SDFS file with this file in the same directory I get the following error

ERROR: Unable to fit variable SDC_buffer

I'm using PBP 2.50, MPASM 5.22, and MCS 3.0.0.5. Any help would be greatly appreciated. Thank you.

Robert

[mackrackit]

Unfortunately it looks like you need a chip with more memory to do both.

Any way you could use two MCUs and have them share data? Not the best solution but... it is all I can think of off the top.