Picbasic MMC SD : sdfs3.bas

[iw2fvo]

Hi to all,
I am going to interface an SD MMC card with a pic18f452 programmed with PicBasicPro 2.50. I included the SDFS.BAS program in my basic code.
I then started to modify the SDTEST3.bas in order to make it compatible with my currently used hardware based on 18f452. The pic has a 10Mhz xtal and I enabled the x4PPL to get 40 Mhz clock speed. I did try to slow the clock speed by removing the x4PLL leaving the pic operating at 10 MHZ but with no changes in the operation.
The voltage level has been adapted usinh a three resistors divider ( 1k8 / 3k3 ) as indicated in other projects on the web.
The pic runs correctly, it talks on the serial port with my PC but I still have init : 400, init : 620, init 860, init: 623... errors.
I used 128 M , 256 M and 1 G cards with no improvements.
The three cards work well on my camera.

I attach to this message my modified basic code.
I will appreciate to receive your suggestion, directions, ..help in order to solve the problem.
Thanks in advance.
Ambrogio
IW2FVO

[Art]

There doesn't appear to be any code attached.

Where did you get the original code for interfacing SD cards if you don't mind my asking?

[iw2fvo]

I did the procedure to attach the file but it not there !
let me try again
The program has been taken from MeLabs SDFS3.zip.

There doesn't appear to be any code attached.

Where did you get the original code for interfacing SD cards if you don't mind my asking?

[iw2fvo]

It is me again,
i did the procedure to attach the file but it is still not there.
Any help in attaching it ?
Thanks
Ambrogio

There doesn't appear to be any code attached.

Where did you get the original code for interfacing SD cards if you don't mind my asking?

[iw2fvo]

try to attach again
Ambrogio

There doesn't appear to be any code attached.

Where did you get the original code for interfacing SD cards if you don't mind my asking?

[mackrackit]

Try changing this line to not use the hardware.

SDC_UseHardSPI = TRUE	' Use hardware SSP port for SPI.

I think you have the PIC pins mixed up.

And I think you will have better luck if you run the PIC from a 4MHz clock. Then you can run the whole thing from 3 volts and not have to worry with the resistors.

Do you have the SD pins 8 and 9 pulled up to 3 volts? That is also needed.

[iw2fvo]

Thanks a lot for the instructions:
I will put:
*SDC_UseHardSPI = False
*a new 4 Mhz xtal
* possibly a 3v3 power supply
Yes, pins 9 and 9 have a pull up of 10K to 3v3.
I will let you know the resultsby tomorrow evening .
Thanks again
Ambrogio

Try changing this line to not use the hardware.

SDC_UseHardSPI = TRUE	' Use hardware SSP port for SPI.

I think you have the PIC pins mixed up.

And I think you will have better luck if you run the PIC from a 4MHz clock. Then you can run the whole thing from 3 volts and not have to worry with the resistors.

Do you have the SD pins 8 and 9 pulled up to 3 volts? That is also needed.

[iw2fvo]

Hi,

I did all the changes... no improvement at all.
The pic has to be programmed at 5Vdc. I then changed the power supply voltage to 3v3. No change.

Thanks
Ambrogio
North Italy

Try changing this line to not use the hardware.

SDC_UseHardSPI = TRUE	' Use hardware SSP port for SPI.

I think you have the PIC pins mixed up.

And I think you will have better luck if you run the PIC from a 4MHz clock. Then you can run the whole thing from 3 volts and not have to worry with the resistors.

Do you have the SD pins 8 and 9 pulled up to 3 volts? That is also needed.

[mackrackit]

What errors are returned?
For example, what do you receive here?

Gosub FSInit
	Serout2 PORTC.6, 16780, ["Init: ", Dec FAT_error, " ", Dec SDC_status, " ", Dec SDC_response, $d, $a]