how to leave ports 49/up and 50/down as Uplink - enterasys A4H124-48P

[Ol24h]

I have an Enterasys A4H124-48P switch and I want to know how to make ports 49/up and 50/down as Uplink, as I want to use them as 10/100/1000BASE-T Ethernet ports through RJ45 connectors and not as stacking