MEMORY PARTITIONS

4.2.2.4Unsupported Locations Windowing Example

Assume that you wish to access location 1FF1H (the P5_MODE register, a memory-mapped SFR) with register-direct addressing through a 128-byte window. This location is in the range of addresses (1FE0–1FFFH) that cannot be windowed. Although you could set up the window by writing 1FH to the WSR, reading this location through the window would return FFH (all ones) and writing to it would not change the contents. However, you could access the peripheral SFRs in the range of 1F80–1FDFH with their windowed direct addresses.

4.2.2.5Using the Linker Locator to Set Up a Window

In this example, the linker locator is used to set up a window. The linker locator locates the window in the upper register file and determines the value to load in the WSR for access to that window. (Please consult the manual provided with the linker locator for details.)

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8XC196Kx, Jx, CA USER’S MANUAL

public function2 extrn ?WSR

The following is an example of a linker invocation to link and locate the modules and to determine the proper windowing. (This example assumes an 8XC196CA, JT, JV, KS, or KT.)

RL196 MOD1.OBJ, MOD2.OBJ registers(100h-03ffh) windowsize(32)

The above linker controls tell the linker to use registers 0100–03FFH for windowing and to use a window size of 32 bytes. (These two controls enable windowing.)

The following is the map listing for the resultant output module (MOD1 by default):

SEGMENT MAP FOR mod1(MOD1):

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