- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
I am interfacing an ADC (AD9461) to the HSMA breakout board on my Cyclone III dev board. The ADC is 16-bits clocked at 7MHz. I measured this LVDS signal at 1.5V high and 1.0V low, which I assume conforms to the Cyclone "2.5V LVDS" based on this note: http://www.interfacebus.com/voltage_interface.html
I assume I can program any of these GPIO pins to be clock pins right? Otherwise I only see a single ended clock option (pin 2 HSM_CLKIN0) It seems like programming two IO pins for my differential clock feed is superior to only using one end of my differential clock to feed the HSM_CLKIN0 clock pin. Is this correct?Link Copied
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Good luck mate. I believe that you can program the GPIO pins. :)
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Thanks for the encouragement. It looks like the ALTLVDS block allows you to only assign the positive differential pin and then it assumes the negative pair pin in the design. This locks you in to using only differential pins to drive the block, which is probably a good idea anyhow. On the CIII Kit HSMC header there appears to be designated Tx and Rx differential pins. Since I'm only driving data into the board, and I'm running out of Rx pins, I tried using the Tx pins as input pins. Seems to work okay in my initial tests. Any reason I can't use the Tx pins as input pins?
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page