Semedo has missed the Addicks' last three games with a pelvic problem and is not expected to be risked against the League Two side so Matt Spring will once again start in the centre of the field.
Fellow midfielder Dean Sinclair is the only other injury absentee with a knee problem.
Boss Phil Parkinson could make changes for the game with Izale McLeod likely to be handed a rare start in attack.
Defender Sam Sodje made his full debut in Saturday's goalless draw at Leeds and could keep his place at The Valley.
Scott Wagstaff, Alex Stavrinou, Tamer Tuna and Chris Solly will also come into Parkinson's thinking.