How does one control TTL output levels

[Jeremy-aero]

I have a DAQ (PCI-6229) set up to send out TTL to several devices. When I read the actualy output voltage between DGND and my ports, I am seeing about 5.14 volts out across the board. Is there a way to set this to exactly 5? I'm trying to avoid ground-loops inside of my device if at all possible. Thanks!

[jschwartz]

Hi Jeremy,

The PCI-6229 does not have programmable logic levels.  One way that you could reduce that voltage would be to use some external circuitry, like a voltage divider.