How to manually get initramfs prompt at boot

I'm trying to get an initramfs prompt at boot because I have no USB drives or anything that I can use, and I need to use fsck on my /dev/sda, but that's obviously not allowed while it's mounted. It's not bad enough that I get the prompt, but it still appears to fix a few things every once in a while at boot. So my question boils down to:

**How can I stop or pause the boot process, on Arch Linux, to get an initramfs prompt?**
(I'm sorry if this isn't possible on Arch, I'm coming from Debian)