I don't have a GC controller, I have a HORI Battle Pad, there is just the digital part of the triggers on this one, not analogue

Hi, I've been practicing OoT for a quite long time now on RetroArch (I downloaded it to play Randomizer originally), but now that I want to do runs, I need to use Project64. But there is just one little problem: this emulator thinks the triggers on my controller are a single axis (R being axis Z- and L being axis Z+), so when I press both it's the same as if I was pressing none of them. Hence I can't target and use the shield at the same time, which is something quite useful in OoT. Is there a way to tell PJ64 to use the triggers as buttons and not an axis, or do I have to buy another controller ? I use Project64 version 1.7.0.50 (downloaded from https://www.speedrun.com/oot/resources) My controller is a HORI Battle Pad (the one they released for Smash Ultimate)