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write time ?

eyals111
Associate II
Posted on February 17, 2014 at 09:54

hi , 

1.what is the page size in M24SR-16  ?  in the datasheet its declared  that 

   write time for page in I2C = 5ms , write time for up to 264 bytes =150ms 

2.Is it normal after writing 5 bytes to the  M24SR , i am getting Frame extension of            

   2*9.6ms ?

3.when authenticating using password in order to gain Read / Write Access , does it much    time as writing 16 bytes ?

#fwi #m24sr #i2c #m24sr #ndef
1 ACCEPTED SOLUTION

Accepted Solutions
Anais GALLIGANI
Senior II
Posted on March 05, 2014 at 11:42

Hello,

Please find here below answer to each point

 

1. In Scenario  1,3  the R-APDU  you got is 036A824F75     =>  SW1=6A  SW2=82   ,which means   ''File or Application Not Found''  (Table 24 Datasheet) , So the Write Process Didn't Start .
  • This mean the sequence applied was not correct .

  • Before to access or update a NDEF  it is need to

    • s

      elect correctly the application

    • Select correctly the file

  • Then you can access the file for reading or writing

2.In Scenario 2,4 the S-Block  you got is F2020A72   , Which is Frame Extension request from the IC.

  • F2 service Instruction  (waiting time extension , no DID)

  • 02 WTX parameter

  • 0A72   CRC

  • The M24SR calculate by itself the requested time extension parameter WTX  in function of the Update request .

  • In your case WTX parameter is equal to “02â€�

  • The reader Must Acknowledge by sending the same service instruction thus in your case  F202  0A72

  • After what the update will start .

Have a nice day,

Best Regards,

ST NFC/RFID Dynamic tag e2e support

View solution in original post

3 REPLIES 3
Anais GALLIGANI
Senior II
Posted on February 19, 2014 at 18:41

Hello,

°) 16 byte ,  but the M24SR is organized in file ,

So the write time is function of several parameters :

-

         

If we change or not the message Length (offset 00 but physically outside the user area)  (1  programming time)

-

         

the number N of physical  page supporting the message  ( N * programming time)

-

         

and FWI = 9.6 ms authorizing only 1 Prog

Thus

1)

     

Change P1P2 :  1 prog , No extension

02-19-2014 16:33:16         NFC SEND I-Block

                                                >>> CR95HFDLL_SENDRECV,

0300D6000002000BB889

08

                                                <<< 8008 

036A824F75

  080000

2)

     

Change P1P2 :  1 prog + 1 byte ,    2  Prog    ,  Extension request ->  Accept extension  , Pog OK

02-19-2014 16:37:40         NFC SEND I-Block

                                                >>> CR95HFDLL_SENDRECV,

0300D6000003000BD1F5E2

08

                                                <<< 8007

F2020A72

080000

02-19-2014 16:37:40         NFC SEND SWTX_Block

                                                >>> CR95HFDLL_SENDRECV,

F2020A72

08

                                                <<< 8008

0390002D53

080000

3)

     

Change  14 byte , first row (except P1P2)     1  Prog      , Pog OK

02-19-2014 16:31:51         NFC SEND I-Block

                                                >>> CR95HFDLL_SENDRECV,

0200D600020ED1011F55017777772E73742E636FCE80

08

                                                <<< 8008

026A82932F

  080000

4)

     

Change  2 byte , first & second row      2  Prog    ,  Extension request ->  Accept extension  , Pog OK

02-19-2014 16:40:53         NFC SEND I-Block

                                                >>> CR95HFDLL_SENDRECV,

0200D6000F02636FE1D0

08

                                                <<< 8007

F2020A72

  080000

02-19-2014 16:40:53         NFC SEND SWTX_Block

                                                >>> CR95HFDLL_SENDRECV,

F2020A72

08

                                                <<< 8008

029000F109

080000

2°)  For me the first extension occurs when programming on two page  ,

Don’t forget to respond to a Service command  “Waiting time Extensionâ€� request ie:

F2020A72

 by the same Service command ie:

F2020A72

3°) Yes this is normal , purpose to prevent from hacking by increasing the command  time ( there is none physical writing)

I hope this is clear enough,

Best regards,

ST NFC/RFID Dynamic support

eyals111
Associate II
Posted on February 23, 2014 at 11:55

Thanks for the quick reply ,

1. In Scenario  1,3  the R-APDU  you got is 

036A824F75

     =>  SW1=6A  SW2=82   ,

which means   ''File or Application Not Found''  (Table 24 Datasheet) , So the Write Process Didn't Start .

2.

In Scenario 2,4 

the S-Block  you got is 

F2020A72   ,

Which is Frame Extension request from the IC.

from what understand page size is 16 Bytes , but there are few exception :

1.If i change the NDEF message length bytes , it will take 1 Prog time .

2.The Number of Page I am crossing during Write , Number of Page * 

Prog time

If you can clarify your reply I really appreciate.

Anais GALLIGANI
Senior II
Posted on March 05, 2014 at 11:42

Hello,

Please find here below answer to each point

 

1. In Scenario  1,3  the R-APDU  you got is 036A824F75     =>  SW1=6A  SW2=82   ,which means   ''File or Application Not Found''  (Table 24 Datasheet) , So the Write Process Didn't Start .
  • This mean the sequence applied was not correct .

  • Before to access or update a NDEF  it is need to

    • s

      elect correctly the application

    • Select correctly the file

  • Then you can access the file for reading or writing

2.In Scenario 2,4 the S-Block  you got is F2020A72   , Which is Frame Extension request from the IC.

  • F2 service Instruction  (waiting time extension , no DID)

  • 02 WTX parameter

  • 0A72   CRC

  • The M24SR calculate by itself the requested time extension parameter WTX  in function of the Update request .

  • In your case WTX parameter is equal to “02â€�

  • The reader Must Acknowledge by sending the same service instruction thus in your case  F202  0A72

  • After what the update will start .

Have a nice day,

Best Regards,

ST NFC/RFID Dynamic tag e2e support