3 Replies Latest reply on Apr 30, 2012 7:13 PM by 893199

# Smart card baud rate question

Dear all,
I have a question about smart card baud rate:

- What Does F/D value indicated in the ATR in the negotiable mode show?
Does it show the max F/D value? As you know according to the following formula, as much as the F/D value gets greater, the transmission rate gets smaller:
baud rate = f / (F/D)
So if the F/D value in the negotiable mode is the max value, the transmission rate will be kind of the min value?!!!
I,ve got confused in this problem, please help me!

regards,
• ###### 1. Re: Smart card baud rate question
Is there anyone to help me????
• ###### 2. Re: Smart card baud rate question
i think ATR indicates Fi = max value of F and Di = max value of D in TA(1)
but greater values of F and D do not mean that F/D is greater
1 person found this helpful
• ###### 3. Re: Smart card baud rate question
Best thing to do is pay the money and get a copy of ISO7816-3 where all the bit twiddling is described. The ins and outs of the various card options are legion and its best to go to the source if its important.