Hewlett Packard has released a firmware update. This replaces the beta firmware from last November (details can be found here: https://edspi31415.blogspot.com/2017/11/hp-prime-public-beta-firmware-rev-12951.html).
Details here: http://www.hpmuseum.org/forum/thread-10061.html
Link to versions of the Prime (direct link): ftp://ftp.hp.com/pub/calculators/Prime/
This blog is property of Edward Shore, 2018