Intel 80C186EA, User Manual

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CHIP-SELECT UNIT
6-22
Example 6-1. Initializing the Chip-Select Unit (Continued)
mov dx, MPCS_REG ;ready for PCS lines 4-6
mov ax, MPCS_VAL ;as well as MCS programming
out dx, al
mov dx, MMCS_REG ;set up DRAM chip-selects
mov ax, MMCS_VAL
out dx, al
mov dx, PACS_REG ;set up I/O chip-select
mov ax, PACS_VAL
out dx, al
CODE ENDS
;
;Power-on reset code to get started
;
ASSUME CS:POWER_ON
POWER_ON SEGMENT AT 0FFFFH
mov dx, UMCS_REG ;point to UMCS register
mov ax, UMCS_VAL ;reprogram UMCS to match system
out dx, al ;requirements
jmp FW_START ;jump to initialization code
POWER_ON ENDS
;
;Data segment
;
DATA
SEGMENT PUBLIC 'DATA'
DD 256 DUP (?) ;reserved for interrupt vectors
;Place memory variables here
DW 500 DUP (?) ;stack allocation
STACK_TOP LABEL WORD
DATA ENDS
;Program ends
END