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RE: ECP problem



Hi,

>1. HostClk retains high 
>2. PeriphACK change from LOW to HIGH
>3. HostCLK change from high to LOW.
>4. HostCLK retains high and
>   PeriphACK retains LOW.

If this is true the device violates IEEE 1284. The device
has to wait for the Strobe (HostCLK) before it can ACK
(PeriphACK) the data (the device can't know that there is
data to ACK uless it has seen a strobe).

For the Reverse mode,
I can't make it work.
But i get this :
	
>1. PeriphCLK and HostACK retains HIGH
>2. PeriphCLK trigger and HostACK trigger
>3. Finally retains HIGH again.

Looks correct.

>And also in the forward mode, i got the interrupt
>about the ecp_descr, but in the reverse mode,
>i can't get interrupt of ecp_eop.

>Also, i am not so understand what is the difference
>about ecp_descr and ecp_eop interrupt? and
>in what condition, i should use?

eop is typically used in packet based protocols such
as Ethernet. descr is typcially used when you expect
a specific amount of data.

>Any examples which i can follow other than lpslave ?

Yes, I'll send you an ECP skeleton in a separate
mail.

/Mikael