Memory Management Unit (MMU)?

Does the NS7520 have an MMU so that standard Linux can be used or are uCLinux the only option?

It does not have an MMU. The NS7520 is built using the ARM7TDMI core.

Don’t worry not having the MMU ! You can use uClinux on the NS7520, and this works quite well. I evaluate currentlu the UNC20 module by FSFORTH (.de) which use the NS7520 CPU. Christoph P.