Assembly source code get times of day (fetch time)

INTRODUCTION

The ' the ' is of the ' a program ' uses ' system time of day. This example uses a conditional assembly to decide between two-to-get the "time of". One way is to use the DOS time function; The other way, illustrated by the second code example, uses the "BIOS time" function. The second example can be used to replace the standard DOS call to get the ' time of '. This second example'll return to the time of faster than the standard DOS call.

The EXAMPLE

This example runs until a set time of day occurs and then terminates. This code gets the ' time ' information from the ' DOS command line input data. If There is bad input data, then a error message was displayed, informing the user what the correct input data format is. While the "program is" waiting for the "Terminate time", it would scan the keyboard for the ' escape key to terminate ' program on user demand.

; Wait for TIME
; This program can be executed inside of a. BAT file to
; Stall execution of the. BAT file until a set time of
;?????????????????????????????????????????????????????????? ???
Conditional assembly flag, 0 to-use DOS, 1 to-use BIOS example
. MODEL Tiny
Use_bios_flag EQU 1
;-----------Stack Area---------------
. STACK 500
;--------------------------------------
. CODE
;*************　@@@@@@@@@@@@@@　***************
Start proc near
MOV bx,80h index command line data
mov al,[bx]; get size of string variable
MOV Ax,cs
mov ds,ax; reset data segment
MOV psp_seg,es; save PSP Address
mov es,ax; reset extra Segment
CMP al,4; Is there data in string
JB Exit_bad; Branch if no data
Inc BX
Inc BX;p oint to start of data
; Get number out of buffer area
Call Get_number
JC Exit_bad Branch If number bad
MOV wait_hour,al save number in hour
CMP al,23;?? Number too large??
JA Exit_bad branch is too large
; Check the number terminating character
CMP Ah, ":"
jne Exit_bad; branch if not:
;p oint to start of next
Inc BX
; Get next number out of the buffer area
Call Get_number
JC Exit_bad Branch If number bad
CMP al,59;?? Number too large??
JA exit_bad; branch if too large
MOV wait_minute,al save number to minute
;d isplay executing wait message
mov ah,9; set DOS function number
Lea Dx,wait_message
int 21H;D OS call to display message
;________________________________
;**********　!!!!!!!! **********
Wait_loop:
; scan keyboard for keys
MOV ah,1
int 16H
JZ wait_no_key; branch if no key
MOV ah,0 If here then keyboard data
int 16H; Get key code from buffer
CMP ax,3b00h Check Key code
JE Exit branch if exit key
CMP al,1bh Check for ESC key
JE Exit; branch if ESC key
Wait_no_key:
; Find out what time it is
; Conditional Assembly????????????????????
; Use this code if linking to code in this section
IF Use_bios_flag
Call Get_time_of_day
; Else use this code if calling DOS for time
ELSE
MOV ah,2ch
int 21H;
ENDIF
CMP Ch,wait_hour
Jne Wait_loop Loop if not
CMP Cl,wait_minute
Jne Wait_loop Loop if not
;^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Exit
MOV ah,4ch
int 21h; Terminate program
;!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Exit_bad:
MOV ah,9
Lea Dx,exit_bad_message
int 21H;D OS call to display message
JMP exit
; ***** ^^^^^^^^ ***** ^^^^^^^^ ****
Get_number:
; On entry BX indexes ASCII Number data into PSP segment area
; On exit if carry clear,
; Register AL has binary number, from 0 to 99
; BX indexes past the number,
; AH has exiting character code indexed by BX
Push DS
MOV ds,psp_seg
MOV AL,[BX]
Inc BX
Call Number_check
JC Get_number_bad
MOV Ah,al
MOV AL,[BX]
Call Number_check
JC Get_number_1
GET_NUMBER_2A:
CMP ah,0
Je get_number_2
Add al,10
Dec AH
JMP get_number_2a
Get_number_2:
Inc BX
MOV Ah,al
MOV AL,[BX]
Get_number_1:
CMP al, ":"
Je get_number_1a
CMP AL,0DH
Jne Get_number_bad
GET_NUMBER_1A:
Xchg Al,ah
Pop ds
CLC; set good number flag
Ret
Get_number_bad:
Pop ds
STC; set bad number flag
Ret
;#################################################
Number_check:
; This code checks for ASCII number in AL
; If it finds a number, then it makes it binary
; and returns with carry clear, else carry set
CMP al, "0"
JB Number_bad
CMP al, "9"
JA number_bad
and AL,0FH
Clc
RET STC
Ret
;*************************
Start ENDP
; +++ This routine combines the data and code into one segment +++
; Define data area
PSP_SEG DW 0
Wait_hour DB 0
Wait_minute DB 0
Wait_message DB 0dh,0ah,0dh,0ah
DB "Wait in progress, press [ESC] to exit", 0dh,0ah
DB "$"
Exit_bad_message DB 0dh,0ah
DB "To use Timewait program enter timeout data"
DB "from command line as example:", 0dh,0ah,0dh,0ah
DB "Timewait 11:30", 0dh,0ah,0dh,0ah
DB "Note, timeout hours vary from 0 to 23,"
DB "and minutes from 0 to", 0dh,0ah
DB "$"
;______________________________________
End Start