helloh.asm

关于8086的软核fpga代码

;***************************************************************
; Test CALL Instructions	   
;
; version 0.1
;***************************************************************	
;MAX_MEMORY EQU     128                         ; Available memory in KByte, see ADDR_WIDTH generic in MemBlock      
LF          EQU     0Ah
CR          EQU     0Dh

; PIO, 0x398-0x39F
PIO			EQU		0398h

; UART settings, COM1
COM1        EQU     03F8h 
COM2        EQU     02F8h 
COMPORT		EQU		COM1

DATAREG     EQU     0   
STATUS      EQU     1      
DIVIDER     EQU     2

TX_EMPTY    EQU     02
RX_AVAIL    EQU     01
FRAME_ERR   EQU     04

		org  	0400h		    	; result in .com start IP=0100

		MOV		AX,CS
		MOV		DS,AX
		MOV		ES,AX
		
;------------------------------------------------------------------------------------
; Transmit character in AL
; AX Changed
;------------------------------------------------------------------------------------
AGAIN:  MOV     DX,COMPORT+STATUS          
WAITTX: IN      AL,DX                           ; read status
        AND     AL,TX_EMPTY                     ; Transmit Register Empty?
        JZ      WAITTX                          ; no, wait
        MOV     DX,COMPORT+DATAREG                ; point to data port
        MOV		AL,'H'
        OUT     DX,AL

		JMP		AGAIN