Real-time MIDI Input Issues

I trying to use the manual version of real-time, but I am having issues with the insertion of the correct rhythm. The piece is in 4/4 time and I am trying to write in a bass line. I am using a Casio WK-7500 as the MIDI Controller. I am using a assigned my pedal for the real-time advance feature. I start at the beginning of a bar, with real-time (manual) activated and set to a quarter note. I press and hold the key I want, I press my pedal and the rhythm I am left with is a whole note. I noticed if I set it to a half not it gives me 2 whole notes, and if set to a whole note it gives me 4 wholes notes. Any help with this issue? Has anyone else had this?