I thought I'd post this here, just in case I end up losing it and needing it later on. Or whatever...
This was the assignment given:
Write a program to emulate a child's toy which is played by dropping a marble in one of the three holes ( A, B, or C ) at the top of the toy and watching the changes. As the marble moves past switches, the values of the switch are changed. The path which the marble will take is dependent upon the current state of the switch. Your game display should look something like the following: the letters should be displayed, the numbers representing the switch positions, and the value of each switch which is initially a 0:
A B C
1 2 3
0 0 0
4 5
0 0
6 7 8
0 0 0
Treat the toy as a multi-switch device with each switch having two states and being independent of each other. Each switch's input and output are defined as follows:
INPUT :
hole A : the marble goes to Switch 1
hole B : the marble goes to Switch 2
hole C : the marble goes to Switch 3
OUTPUT:
When Switch 1 is 0, the marble goes to Switch 6
When Switch 1 is 1, the marble goes to Switch 4
When Switch 2 is 0, the marble goes to Switch 5
When Switch 2 is 1, the marble goes to Switch 4
When Switch 3 is 0, the marble goes to Switch 5
When Switch 3 is 1, the marble goes to Switch 8
When Switch 4 is 0, the marble goes to Switch 7
When Switch 4 is 1, the marble goes to Switch 6
When Switch 5 is 0, the marble goes to Switch 8
When Switch 5 is 1, the marble goes to Switch 7
When Switch 6 is 0, the marble exits the Toy
When Switch 6 is 1, the marble exits the Toy
When Switch 7 is 0, the marble exits the Toy
When Switch 7 is 1, the marble exits the Toy
When Switch 8 is 0, the marble exits the Toy
When Switch 8 is 1, the marble exits the Toy
The Toy starts with a display of the board having all switches set to 0.
Accept the input from the keyboard (provide an appropriate prompt) of A, B, or C which is the selection of the hole into which to drop the marble. Calculate the state changes of the switches, change them, and then re-display the board in its new state. Continue until the proper exit code is provided. You must idiot proof your program to ignore improper values. Use of procedures and Macros as appropriate is required.
And here's the garbage that I regurgitated into Notepad!
; Toy.asm
;
; What the array looks like when not crammed onto one line.
; a[0,0] is the array element at position [0,0]. and so on.
; Essentially, there are 3 rows, just like the assignment description:
; 1st Row has 3 columns.
; 2nd Row has 2 columns.
; 3rd Row has 3 Columns.
; +--------+--------+--------+
; | a[0,0] | a[0,1] | a[0,2] |
; | OFF 0 | OFF 1 | OFF 2 |
; +--------+--------+--------+
; | a[1,0] | a[1,1] |
; | OFF 3 | OFF 4 |
; +--------+--------+--------+
; | a[2,0] | a[2,1] | a[2,2] |
; | OFF 6 | OFF 7 | OFF 8 |
; +--------+--------+--------+
.MODEL small
.STACK 100h
.DATA
; 1FH = ON
; 7FH = OFF
PRMPT1 DB 10, 10, 13, '[q] Or [Q] To Quit'
DB 10, 10, 13, '[A], [B], [C] To Drop Ball: $'
HEADER DB 10, 10, 13, ' ', 41H, ' ', 42H, ' ', 43H, '$' ; A B C
LINE1A DB 10, 10, 13, ' $'
LINE1B DB ' $'
LINE1C DB ' $'
LINE2A DB 10, 10, 13, ' $'
LINE2B DB ' $'
LINE3A DB 10, 10, 13, ' $'
LINE3B DB ' $'
LINE3C DB ' $'
SWITCHES DB 1FH, 1FH, 1FH
DB 1FH, 1FH
DB 1FH, 1FH, 1FH
.CODE
START PROC
MOV AX, @DATA ; Startup code.
MOV DS, AX
DRAWGAME:
CALL CLRSCRN ; Clear the screen
MOV DX, OFFSET HEADER ; Display menu
MOV AH, 09H
INT 21H
MOV DX, OFFSET LINE1A ; Draw Row 1, Col A
MOV AH, 09H
INT 21H
MOV DL, SWITCHES + 0 ; Display switch 1 value.
MOV AH, 02h
INT 21H
MOV DX, OFFSET LINE1B ; Draw Row 1, Col B
MOV AH, 09H
INT 21H
MOV DL, SWITCHES + 1 ; Display switch 2 value.
MOV AH, 02h
INT 21H
MOV DX, OFFSET LINE1C ; Draw Row 1, Col C
MOV AH, 09H
INT 21H
MOV DL, SWITCHES + 2 ; Display switch 3 value.
MOV AH, 02h
INT 21H
MOV DX, OFFSET LINE2A ; Draw Row 2, Col B
MOV AH, 09H
INT 21H
MOV DL, SWITCHES + 3 ; Display switch 4 value.
MOV AH, 02h
INT 21H
MOV DX, OFFSET LINE2B ; Draw Row 2, Col C
MOV AH, 09H
INT 21H
MOV DL, SWITCHES + 4 ; Display switch 5 value.
MOV AH, 02h
INT 21H
MOV DX, OFFSET LINE3A ; Draw Row 3, Col A
MOV AH, 09H
INT 21H
MOV DL, SWITCHES + 5 ; Display switch 6 value.
MOV AH, 02h
INT 21H
MOV DX, OFFSET LINE3B ; Draw Row 3, Col B
MOV AH, 09H
INT 21H
MOV DL, SWITCHES + 6 ; Display switch 7 value.
MOV AH, 02h
INT 21H
MOV DX, OFFSET LINE3C ; Draw Row 3, Col C
MOV AH, 09H
INT 21H
MOV DL, SWITCHES + 7 ; Display switch 8 value.
MOV AH, 02h
INT 21H
MOV DX, OFFSET PRMPT1 ; Display menu
MOV AH, 09H
INT 21H
GETINPUT:
MOV AX, 0
MOV AH, 08H ; Get user input.
INT 21H
CMP_bA:
CMP AL, 41H ; Is input = "A"?
JNE CMP_sA ; If not, check for "a".
JMP SWITCH1 ; If it is, Jump to Switch #1.
CMP_sA:
CMP AL, 61H ; Is input = "a"?
JNE CMP_bB ; If not, check for "B".
JMP SWITCH1 ; If it is, jump to Swtich #1.
CMP_bB:
CMP AL, 42H ; Is input = "B"?
JNE CMP_sB ; If not, check for "b".
JMP SWITCH2 ; If it is, jump to Switch #2.
CMP_sB:
CMP AL, 62H ; Is input = "b"?
JNE CMP_bC ; If not, check for "C".
JMP SWITCH2 ; If it is, jump to Switch #2.
CMP_bC:
CMP AL, 43H ; Is input = "C"?
JNE CMP_sC ; If not, check for "c".
JMP SWITCH3 ; If it is, jump to Swtich #3.
CMP_sC:
CMP AL, 63H ; Is input = "c"?
JNE CMP_bQ ; If not, check for "Q".
JMP SWITCH3 ; If it is, jump to Switch #3.
CMP_bQ:
CMP AL, 51H ; Is input = "Q"?
JNE CMP_sQ ; If not, check for "q".
JMP EXITPROG ; If it is, jump to EXITPROG.
CMP_sQ:
CMP AL, 71H ; Is input = "q"?
JNE GETINPUT ; If it is not, then user did not enter any of the above keys.
JMP EXITPROG ; If it is, jump to EXITPROG.
SWITCH1:
CMP [SWITCHES + 0], 7FH ; if character in switch 1 is 7FH
JE SWITCH1A
CMP [SWITCHES + 0], 1FH ; if character in switch 1 is 1FH.
JE SWITCH1B
SWITCH1B:
MOV [SWITCHES + 0], 7FH ; switch character to OFF
JMP SWITCH4
SWITCH1A:
MOV [SWITCHES + 0], 1FH ; switch character to ON
JMP SWITCH6
SWITCH2:
CMP [SWITCHES + 1], 7FH ; if character in switch 2 is 7FH
JE SWITCH2A
CMP [SWITCHES + 1], 1FH ; if character in switch 2 is 1FH.
JE SWITCH2B
SWITCH2B:
MOV [SWITCHES + 1], 7FH ; switch character to OFF
JMP SWITCH2
SWITCH2A:
MOV [SWITCHES + 1], 1FH ; switch character to ON
JMP SWITCH5
SWITCH3:
CMP [SWITCHES + 2], 7FH ; if character in switch 3 is 7FH
JE SWITCH3A
CMP [SWITCHES + 2], 1FH ; if character in switch 3 is 1FH.
JE SWITCH3B
SWITCH3B:
MOV [SWITCHES + 2], 7FH ; switch character to OFF
JMP SWITCH8
SWITCH3A:
MOV [SWITCHES + 2], 1FH ; switch character to ON
JMP SWITCH5
SWITCH4:
; Code for Switch #4 goes here.
CMP [SWITCHES + 3], 7FH ; if character in switch 4 is 7FH
JE SWITCH4A
CMP [SWITCHES + 3], 1FH ; if character in switch 4 is 1FH.
JE SWITCH4B
SWITCH4B:
MOV [SWITCHES + 3], 7FH ; switch character to OFF
JMP SWITCH6
SWITCH4A:
MOV [SWITCHES + 3], 1FH ; switch character to ON
JMP SWITCH7
SWITCH5:
CMP [SWITCHES + 4], 7FH ; if character in switch 5 is 7FH
JE SWITCH5A
CMP [SWITCHES + 4], 1FH ; if character in switch 5 is 1FH.
JE SWITCH5B
SWITCH5B:
MOV [SWITCHES + 4], 7FH ; switch character to OFF
JMP SWITCH7
SWITCH5A:
MOV [SWITCHES + 4], 1FH ; switch character to ON
JMP SWITCH8
SWITCH6:
CMP [SWITCHES + 5], 7FH ; if character in switch 6 is 7FH
JE SWITCH6A
CMP [SWITCHES + 5], 1FH ; if character in switch 6 is 1FH.
JE SWITCH6B
SWITCH6B:
MOV [SWITCHES + 5], 7FH ; switch character to OFF
JMP DRAWGAME
SWITCH6A:
MOV [SWITCHES + 5], 1FH ; switch character to ON
JMP DRAWGAME
SWITCH7:
CMP [SWITCHES + 6], 7FH ; if character in switch 7 is 7FH
JE SWITCH7A
CMP [SWITCHES + 6], 1FH ; if character in switch 7 is 1FH.
JE SWITCH7B
SWITCH7B:
MOV [SWITCHES + 6], 7FH ; switch character to OFF
JMP DRAWGAME
SWITCH7A:
MOV [SWITCHES + 6], 1FH ; switch character to ON
JMP DRAWGAME
SWITCH8:
CMP [SWITCHES + 7], 7FH ; if character in switch 8 is 7FH
JE SWITCH8A
CMP [SWITCHES + 7], 1FH ; if character in switch 8 is 1FH.
JE SWITCH8B
SWITCH8B:
MOV [SWITCHES + 7], 7FH ; switch character to OFF
JMP DRAWGAME
SWITCH8A:
MOV [SWITCHES + 7], 1FH ; switch character to ON
JMP DRAWGAME
EXITPROG:
CALL CLRSCRN
MOV AL, 0 ; exit to DOS.
MOV AH, 04ch
INT 21h
START ENDP
CLRSCRN PROC
MOV AH, 0fh
INT 10h
MOV AL, 00h
MOV AH, 0
INT 10h
RET
CLRSCRN ENDP
END START
