RCM4300 Series SRAM differences

I have ported over code from a RCM4210 to a RCM4310 but ran out of root code space with the enhancements. So I picked up a RCM4300 which has 1mb of SRAM, 512 more than the RCM4310. I still get the same error on the RCM4300 as the RCM4310. Does anyone know if there is a memory mapping problem here for the RCM4300 compiling to SRAM. I have traced down through stdbios.c and can’t see any defines that would map the memory differently from the RCM4300 to the RCM4310 yet the parts are not the same. I am using DC 10.21.

Any help with this would be greatly appreciated.