I can see the HUD change when a mortar is deployed in this video. Is there a way to change the HUD zoom during the game?
On PC the keys are
n to switch between small, medium, and large map size
m to switch between small, medium, and large map zoom
I don't know the controller button equivalents for this, unfortunately!
I found this controller layout scheme
Left Bumper Grenade
Left Trigger ADS
Right Bumper Melee, hold to equip knife
Right Trigger Fire
Left Stick Move
Click once to enable run (continues until you release forward)
Click and hold while ADS to steady aim (Recon)
Right Stick Aim
Click to duck, hold to prone
Y Change Weapon
B Enter/Leave Vehicle - Arm/Disarm M-Com
Pad Up Turn on/off torch (when unlocked)
Pad Left Deploy Ammo/Med Pack/ Radio beckon/etc... (when unlocked)
Pad Right Deploy Defib/Rocked Launcher/Motion Sensor/etc... (when unlocked)
Pad Down Change rate of fire
Start Options menu
Back Spot (press), Score board (hold)
But wow, I don't see the map controls anywhere. Maybe they couldn't fit it in there? Can you remap controls on the Xbox? Perhaps there's a way to remap the map zoom/size functions to one of the existing buttons?