=== X-Modul (RS-232 Interface) ===
The "X-Modul" adds a RS-232 interface to -X drives. It is suspecting to be compatible with Amstrad/Pace interfaces (and probably also including, but not using, channel B ports FADE/FADF and FBDE).
==== I/O Ports ====
{| class="wikitable"|-! Port !! Usage|-| FADC/FADD: || Serial data and control|-| FBDC/FBDD/FBDF: || Counter 0/1/Mode So it's probably compatible with Amstrad/Pace (and probably also including, but not using, channel B ports FADE/FADF and FBDE).|}
== Vortex Disk Format ==