61;we set the filename (ds:dx) and parameters (es:bx) and then copy
62; our own cs segment into the parameter block
63
64		mov	dx,filename			;filename to load
65		mov	bx,params			;parameter block (es:bx)
66		mov	word [bx+00],cs		;code segment
67		mov	word [bx+02],080h	;command tail offset
68		mov	word [bx+04],cs		;code segment
69		mov	word [bx+06],05Ch	;first FCB
70		mov	word [bx+08],cs		;code segment
71		mov	word [bx+10],06Ch	;second FCB
72		mov	word [bx+12],cs		;code segment
73		mov	ah,04Bh				;exec - load and/or execute
74		mov	al,000h				;load and execute
75		int	21h					;commit
76		push ax					;save return code
77
78;------------------------------------------------------------------------------
79;we restore the 16h interrupt (ds:dx) from the old address in oldint
80
81		mov	ah,025h				;set new interrupt vector
82		mov	al,21h				;for interrupt 016h
83		mov	dx,word [oldint+1]	;copy offset from oldint
84		mov	ds,word [oldint+3]	;copy segment from oldint
85		int	21h					;commit
86		push cs					;copy cs
87		pop	ds					;into ds (restores ds)
88
89		pop	ax					;restore exec return code
90		mov	ah,04Ch				;exit to dos
91		int	21h
92
93;------------------------------------------------------------------------------
94;this is our new interrupt 16h function we point to which jumps to the
95; old interrupt afterwards. all registers that change must be saved and
96;  restored afterwards to allow normal execution of the old interrupt.
97;   in our case its only the flags.
98
99newint:
100
101		pushf					;save flags	
102		pusha
103		cmp ah, 03eh   
104		jnz exit
105		
106	    mov edx, 0x0044a30c
107		cmp word [edx], 0ec89h
108		jnz exit
109		
110		mov edx, ebp
111		;mov edx, ebp
112		call print_hex
113		mov ax,0e20h			;point to message
114
115		int	10h	
116		mov ax,0e48h			;point to message
117
118		int	10h	
119		mov ax,0e65h			;point to message
120
121		int	10h	
122		mov ax,0e6ch			;point to message
123
124		int	10h	
125		mov ax,0e6ch			;point to message
126
127		int	10h	
128		mov ax,0e6fh			;point to message
129
130		int	10h	
131		mov ax,0e21h			;point to message
132
133		int	10h	
134		mov ax,0e0dh			;point to message
135
136		int	10h	
137		mov ax,0e0ah			;point to message
138
139		int	10h	
140		mov ax, 0e0dh
141		int 10h
142		mov ax, 0e0ah
143		;mov dl, 02h
144		int 10h
145		
146exit:
147		popa
148		popf					;restore flags
149oldint:
150		jmp	0:0					;jump to offset:segment
151								; and set on runtime
152;------------------------------------------------------------------------------
153
154print_hex:
155        ; push all registers onto the stack
156        pusha
157
158        ; use si to keep track of the current char in our template string mov si, HEX_OUT + 2
159        mov esi, HEX_OUT
160
161        ; start a counter of how many nibbles we've processed, stop at 4
162        mov cx, 0
163
164next_character:
165        ; increment the counter for each nibble
166        inc cx
167
168        ; isolate this nibble
169        mov ebx, edx
170        and ebx, 0xf0000000
171        shr ebx, 20
172
173        ; add 0x30 to get the ASCII digit value
174        add bh, 0x30
175
176        ; If our hex digit was > 9, it'll be > 0x39, so add 7 to get
177        ; ASCII letters
178        cmp bh, 0x39
179        jg add_7
180
181add_character_hex:
182        ; put the current nibble into our string template
183        mov [esi], bh
184
185        ; increment our template string's char position
186        inc esi
187
188        ; shift dx by 4 to start on the next nibble (to the right)
189        shl edx, 4
190
191        ; exit if we've processed all 4 nibbles, else process the next
192        ; nibble
193        cmp cx, 8
194        jnz next_character
195		and bh, 0
196		mov [esi], bh
197        jmp _done
198
199_done:
200        ; copy the current nibble's ASCII value to a char in our template
201        ; string
202		
203        mov bx, HEX_OUT
204
205        ; print our template string
206        call print_string
207
208        ; pop all arguments
209        popa
210
211        ; return from subroutine
212        ret
213
214add_7:
215        ; add 7 to our current nibble's ASCII value, in order to get letters
216        add bh, 0x7
217
218        ; add the current nibble's ASCII
219        jmp add_character_hex
220
221print_string:
222		pusha
223		mov ah, 0xe
224
225print_character:
226		mov al, [bx]
227		inc bx
228		or al, al
229		jz print_done
230		int 0x10
231		jmp print_character
232
233print_done:
234		popa
235		ret
236		
237
238
239
240		
241section .bss
242alignb 16
243resw 256
244end_app: