This article has links to download the pinout sheet of devices.
There are a maximum total of 5 Digital channels. All 5 channels can be used for Digital Input. Alternatively, up to three of the channels can be used for Digital Output.
For example, if the maximum of three channels are used for output, that leaves only two channels remaining for input. So any combination of 5 Digital input/outputs is possible, as long as no more than 3 channels are used for output, and the total number of channels does not exceed 5.