@romers -- what are you trying to achieve? Maybe, a "static route" is not what will resolve your issue.
Are you trying to "port-forward" incoming (to your cable-modem) Internet packets to one of the devices on your home network?
Thanks for your reply. I sense I should have asked in a more direct way, so here goes: Can the hitron 2250 as delivered for residential use do static routing from its setup screens or can it not? I am aware that there are work arounds. I thought I might have missed it.
@romers -- Sorry, but I still do not understand what you want to do, and whether "static routing" is what will do the trick.
Once a device on your private LAN obtains an IP-address from the cable-modem's DHCP-server, the device will keep "renewing" that IP-address, ad infinitum. Even if the device is powered-off until the DHCP-lease expires, the cable-modem's router will "remember" the device (by its MAC-address) and will issue a new DHCP-response, with the same IP-address, as it previously issued, when the device is powered-on and sends a DHCP-request. Expressed differently, once a local device receives an IP-address, it will always receive the same IP-address -- call this "static routing", if you wish.
It looks like you may be confusing 'static addressing' with 'static routing'. Static routing is a set-up function at the router that allows for you to manually specify a route to a destination address. Some routers have this capability, and some do not.
Thanks for your thoughts!