Hi there, I have a customer who is using Global Payments to process their transactions. I have done a lot of digging around seeing if there is a way to integrate with Prestashop, and learning that HSBC now use Global Payments to process for their customers, I have found other Prestashop users wondering about the same thing.
It turns out that firstly you'll need an ecommerce merchant ID with Global Payments. Then check out the Global Iris website (that's the software/API), and there's a topic on Prestashop:
https://resourcecentre.globaliris.com/downloads.html?id=164
Turns out that it seems like a pretty easy integration. Global Payments use a module called Realex, which is already part of the Prestashop install. You just need to enable it and fill in the ID and secret.
Apparently you need a subscription for Realex, but I assume if you are with Global Payments that is already covered. I'm waiting for more information on this.
Anyway, hope this helps someone in the future.