"Paul F. Sullivan" <[EMAIL PROTECTED]> wrote:

>Alex, wrote:
>
>>... I am unsure exactly how you setup a DIO card to do this transfer 
>>given that the data must be 100ns offset from the clock pulse and 
>>held for a minimum period of 100ns.
>
>A crude way to meet the setup time is to update the data and raise 
>the clock pulse simultaneously on the card, but feed the clock to 
>your equipment through a hundred feet (or so) of cable. As long as 
>the clock period is greater than 200ns, you'll meet the hold time.

Most handshake protocols do not state a maximum setup time but only
a minimum. This means you can simply activate the data first and then
the handshake line and deactivate the handshake before removing the
data.

Hardware protocols which do have strict minimum AND maximum setup
times are just a total bitch to implement and certainly not possible
without special hardware support or sometimes you can get away with
a HARD realtime operating system and software.
 
Rolf Kalbermatter
CIT Engineering Nederland BV    tel: +31 (070) 415 9190
Treubstraat 7H                  fax: +31 (070) 415 9191
2288 EG Rijswijk        http://www.citengineering.com
Netherlands             mailto:[EMAIL PROTECTED]
 


Reply via email to