Before you can use your MPC hardware to controll Logic Pro X, will need to open the MPC 2.0 software as a plugin inside of the DAW. The following article walks you through how to do that: Akai Pro MPC X and MPC Live - Complete Setup And Routing in Logic Pro X (force.com).
Use the arrow on the mode bar to select MIDI Control mode.
Alternatively, you can use your MPC hardware to open MIDI Control mode: Go to Menu > Main Mode > MIDI Control
You can use the key command:
SHIFT + Opt + K
or go to:
Logic Pro X > Control Surfaces > Controller Assignments
You can choose either one!* Both options will allow you to map the same way but in expert view you can organize and manage your mappings more (recommended if you use multiple MIDI Controller devices).
*Note: Expert View can only be selected if “Advanced Tools” is enabled in the Logic Pro X Preferences. To enable this setting, go to Logix Pro X > Preferences > Advanced > Enable All
On Expert View you can click on the plus buttons at the bottom to create and save a specific MIDI mapping. You’ll be able to use this mapping in other Logic Pro X projects.
For this example we will create a “Zone” called MPC One (This step is optional):
1. Click on Learn Mode (Expert view) or Learn (Easy view). When you click Learn Mode the button will turn blue and Logic will be ready to assign a control.
2. Click on the desired control to map in Logic Pro X. For this example, we will select the Play button in Logic Pro X (Note: because I clicked on the Play button Logic will start playing. This is normal and will happen with any other button you click inside of Logic). Notice how Logic recognizes the Play command at the top right of the Controller Assignments window:
3. Press or move the desired button or knob on your desired hardware. On your Controller Assignments window, under MIDI Input Message, notice how Input indicates “Any”. This means Logic is ready for you to send a MIDI message by pressing or moving a button or knob in your hardware. We will press the Play button for this example. Once we do that the Controller assignments window will look like this:
Notice how we now have “Play” listed under Parameters and it is listed as "Learned". This means the midi mapping is saved!
On the example above we did a very simple mapping of the Play button. However, this mapping is only the tip of the iceberg when it comes all the possibilities and all the different workflows you can use midi mappings with. The steps above can help you map buttons, knobs and faders, Logic and 3rd-party plugins inside of Logic Pro X. You can also create different sets of mappings for different purposes by creating new "Modes" and mappings for different pieces of gear by creating new "Zones" the Controller Assignments window. Last, you can take even more control of your specific MIDI mappings by using the MIDI Input Message, ASC Message Paths, and Value sections in the Expert View of your Controller Assignments window. When it comes to MIDI mapping your MPC hardware in Logic Pro X the possibilities are as abundant as your workflows might require.