Initializing The Refresh Control Unit - Intel 80C186XL User Manual

$mod186
name example_80C186_RCU_code
; FUNCTION: This function initializes the DRAM Refresh
; Control Unit to refresh the DRAM starting at dram_addr
; at clock_time intervals.
; SYNTAX:
; extern void far config_rcu(int dram_addr, int clock_time);
; INPUTS: dram_addr
; clock_time - DRAM refresh rate
; OUTPUTS: None
; NOTE:
; required by high-level languages.
RFBASE equ
RFTIME equ
RFCON equ
Enable equ
lib_80186 segment public 'code'
assume cs:lib_80186
public _config_rcu
_config_rcu proc far
push bp
mov
_clock_time equ
_dram_addr equ
push ax
push cx
push dx
push di
Example 7-1. Initializing the Refresh Control Unit
- Base address of DRAM to refresh
Parameters are passed on the stack as
xxxxh
xxxxh
xxxxh
8000h
bp, sp
word ptr[bp+6]
word ptr[bp+8]
REFRESH CONTROL UNIT
;substitute register offset
;enable bit
;save caller's bp
;get current top of stack
;get parameters off
;the stack
;save registers that
;will be modified
7-11