Interfacing mmc to PIC 16f72 using PICBasic

[ankit-max]

Hello,

I have a micro sd card which I put in to the mmc adapter. I have connected mmc to the PIC using this configuration:-


I'm using PIC 16f72 which has a SSP module in-built. The code I've written in PICBasic is shown below:-

Device 16F72
Xtal 4

'For RS-232 Communication
Declare Serial_Baud 9600
Declare Rsout_Mode true
Declare Rsin_Mode true
Declare Rsout_Pin PORTB.6
Declare Rsin_Pin PORTB.7

Output PORTB
Output PORTC.2  'CS
Output PORTC.3  'SCK of micro 
Output PORTC.5  'SDO of micro
Input PORTC.4   'SDI of micro 

Symbol SSPEN = SSPCON.5
Symbol CS = PORTC.2
Symbol SMP = SSPSTAT.7
Symbol CKE = SSPSTAT.6
Symbol CKP = SSPCON.4
Symbol BF = SSPSTAT.0
'Using clock = f/16 for 4 MHz (Crystal Frequency)
SSPCON.0=1
SSPCON.1=0
SSPCON.2=0
SSPCON.3=0
Dim kk As Byte    'for data
Dim cnt As Byte
Dim rd As Byte
GoTo main

'To send data to the Memory Card
spi_write:
SSPBUF=kk
While BF = 0
Wend
Return
'To read data from the memory card
spi_read:
SSPBUF=kk
While BF = 0 
Wend
rd = SSPBUF
Return
'Initilization of memory card
mmc_init:
kk=$FF
'Sending 0xFF for the clock
For cnt = 1 To 50
GoSub spi_write
Next cnt
CS = 0 'Chip select low and now send command
DelayMS 50
GoSub spi_write
kk=$40   'For command 0-> 0x40
GoSub spi_write
kk=$0    'Sending 00 00 00 00
GoSub spi_write
GoSub spi_write
GoSub spi_write
GoSub spi_write
kk=$95   'sending CRC value ->  0x95
GoSub spi_write
Return

main:
cnt=0
CS = 1
SSPEN = 1
SMP = 1
CKE = 1
CKP = 0
RSOut "for command o",13,10
GoSub mmc_init
cnt=0
kk=$FF 'Sending last byte and reading the response. 0x01 -> success
GoSub spi_read
Hmm:
If rd = 1 Then
RSOut "Command 0 executed",13,10
ElseIf cnt<1000 Then
GoSub spi_read
cnt=cnt+1
GoTo Hmm
EndIf
RSOut "Failed!!",13,10
End

The problem is I'm not getting a required response for Command 0 :- 0x01. I get 'Failed!!'

P.S. I've used LM317 to give 2.6-3.3 v to the mmc. Right now the voltage at mmc Voltage pin is 2.9V

 

[ankit-max]

Any ideas guys?

 

[jpsganesh]

try this link buddy
https://www.edaboard.com/threads/110758/

and solved thread for 18F2550.
https://www.edaboard.com/threads/268630/

 

[ankit-max]

Oh, thanks mate. Someone replied after such a long time.

Well I will check the link thoroughly. Thank you!

 

[jpsganesh]

Oh, thanks mate. Someone replied after such a long time.

Well I will check the link thoroughly. Thank you!

any update?