All is clear :)
Thanks!
Eran
On Fri, May 18, 2012 at 11:50 AM, Harald Welte <laforge(a)gnumonks.org> wrote:
On Fri, May 18, 2012 at 11:38:07AM +0300, Eran Duchan
wrote:
Harald,
Thanks for your detailed answer.
Furthermore, a "passive slave" shall of
course not signal any parity
error to the master, as it is up to the real slave to determine that.
The latter can be explicitly configured in the Atmel USART.
Are you hinting that parity generation will not work when configured
to be a slave (i.e. external clock)?
No. Please read the data sheet. In ISO7816 mode you can explicitly
switch that on or off. I guess they put that in for T=1 support. Also,
it was my mistake, it is not parity that you're switching, but the
explicit nack in the waiting time after a character.
Atmel is
known to use the same IP cores in a lot of their chips, and the
sam3s is more or less just the sam7s which replaces the arm7tdmi core
with a cortex-m3. There are some other improvements like more USB
endpoints, but I haven't seen any indication of changes in the USART.
That makes sense. Has the SAM3S version been prototyped yet? Have you
seen this functionality work on the SAM3S USART?
no. They are pin-compatible, so it should be easy to re-work one board
with hot air. The bigger differences are in the software (arm vs.
thumb2, exception vectors, ...). I think zecke had done some work here
in the past, but I'm not sure of the status.
See Table
7 if ISO 7816-3. Di > 0x8 is "divide by 1/2, 1/4, 1/8, ..."
which is the same as multipliciation by the divisor.
This is rather interesting. I am looking at ISO 7816-3_2006 and there
are no such values (Table 8: Di[x] = RFU, 1, 2, 4, 8, 16, 32, 64, 12,
20, RFU, RFU, RFU, RFU, RFU, RFU).
I have a paper version of th original spec from 1989, and there it
clearly is stated.
Regards,
Harald
--
- Harald Welte <laforge(a)gnumonks.org>
http://laforge.gnumonks.org/
============================================================================
"Privacy in residential applications is a desirable marketing option."
(ETSI EN 300 175-7 Ch. A6)