I wanted to know how to move the code and data segments of the RTX51 Tiny to specific memory locations. I know how to move regular segments that are created by me using the SEGMENTS Linker Directive. When I try this with the RTX51 tiny segments I get an L113 error which says that the segment has an absolute memory location.
So maybe you should start by telling exactly _why_ you want to move around the code. It's important to talk about "what I want to solve" and not just "how I want to solve" since quite a number of forum threads are resulting from people selecting the wrong route when trying to reach a goal.
So what segment did you get problems with - being an OS kernel, it's quite reasonable that there may be absolute references in the code. Especially if involving the SFR region. But the 8051 is weak in most kinds of indexed addressing which may motivate a bit "interesting" code to solve a problem the 8051 chip was never intended to manage.
For the particular application, I have 1KB of ROM space available and 16KB of OTP. I wanted to put all of the code and data related to the RTOS in the ROM space and place the remaining application code in OTP