Peterson is scheduled to be practicing by Sunday after agreeing Saturday to a four-year, $18.5 million contract with a fifth year at the team's option. The cornerback from LSU was the fifth player taken overall in the draft and a major reason the Cardinals were willing to part with Dominique Rodgers-Cromartie as part of the trade to bring quarterback Kevin Kolb from the Philadelphia Eagles.
Coach Ken Whisenhunt confirmed the deal when he met with reporters after the team's first training camp practice on Saturday.
Earlier Saturday, Arizona further addressed the cornerback position by signing free agent Richard Marshall to a one-year deal. Marshall started all 32 games for Carolina the past two seasons.
Peterson was en route to Arizona from Florida, ready to take his spot at one cornerback spot. Marshall could fill the other, although he will face competition from Greg Toler.
The Cardinals sought to fill another need by signing free agent guard Floyd Womack, an 11-year NFL veteran who played in 16 games for Cleveland last season. Arizona lost starting right guard Deuce Lutui, who signed with Cincinnati.
Womack is the second new guard on the line. Daryn Colledge, a starter on the Green Bay Packers' Super Bowl championship team, signed a free-agent deal with Arizona, taking the spot left open by the retirement of Alan Faneca.
Information from The Associated Press contributed to this report.