It's released on the ICEBOX page.
This is the rom to have if you own a NoV-32 or NoV-64. To sum up:
The functions N100, N101, N102, N200, N201, N202 and N103 allows for fast switching between the various ROM and RAM blocks in the NoV modules (N102, N103, N202 and N203 is for the NoV-64). These functions can be assigned to keys to make it lightning fast to switch blocks. Switching the RAM blocks are instant (the last digit) while switching ROM blocks (the first digit) requires the calc to be powered off and back on to effectuate the switch.
The function NX writes the content of X into address 4100 (the address that holds the NoV-32/64 config).
The function N? shows the current config (the content of address 4100)
NBS (NoV Block Switch) makes it easy to switch to a new config and restore Main Memory to a file named "N" in the new RAM block in one function. NBS is a prompting function that only accepts input in the ranges 000-003, 100-103 and 200-203. An input outside these ranges results in "DATA ERROR". If the file "N" or the function HGETA are not found, a "NONEXISTENCE" is displayed. If you switch the ROM
block (first of the three digits prompted for), the message "CALC
OFF" is briefly displayed to remind you that you need to turn the calc off and on to complete the ROM block switch.
SAVEN saves Main Memory to a file called "N" in the current HEPAX RAM block.
GETN restores Main Memory from the file "N" in the current HEPAX RAM block.
And there are lots of other function suitable for various purposes. The user manual is your friend :-)