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 # 65X-DOS
 
 This source tree builds a 512KB .bin file used to burn the system ROM
-for Sentinel 65X. It consists of modules:
-
- - boot: initial boot code
- - kernel: the OS kernel
-
-In future, more modules are planned:
+for Sentinel 65X. It is designed to be modular; the kernel and boot code
+use only the lowest 64KB of the 512KB ROM, leaving plenty of room for
+additional software in ROM. In future, more modules are planned:
 
  - A command line shell
  - A 65816 macro assembler