source: xtideuniversalbios/trunk/Assembly_Library/Src/Display/DisplayContext.asm@ 44

Last change on this file since 44 was 44, checked in by Tomi Tilli, 14 years ago

Spaces can now be generated before format specifier when printing formatted string.
Background character and attribute can now be easily specified before compiling.
File size: 7.8 KB
Line 
1; File name : DisplayContext.asm
2; Project name : Assembly Library
3; Created date : 25.6.2010
4; Last update : 27.9.2010
5; Author : Tomi Tilli
6; Description : Functions for managing display context.
7
8; Section containing code
9SECTION .text
10
11;--------------------------------------------------------------------
12; DisplayContext_Initialize
13; Parameters:
14; DS: BDA segment (zero)
15; Returns:
16; Nothing
17; Corrupts registers:
18; AX, DX, DI
19;--------------------------------------------------------------------
20ALIGN JUMP_ALIGN
21DisplayContext_Initialize:
22 call .DetectAndSetDisplaySegment
23 mov WORD [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fnCharOut], DEFAULT_CHARACTER_OUTPUT
24 mov WORD [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.wCursorShape], CURSOR_NORMAL
25 mov BYTE [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bAttribute], SCREEN_BACKGROUND_ATTRIBUTE
26 mov BYTE [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bFlags], FLG_CONTEXT_ATTRIBUTES
27
28 xor ax, ax
29 call DisplayCursor_SetCoordinatesFromAX
30 jmp SHORT DisplayContext_SynchronizeToHardware
31
32;--------------------------------------------------------------------
33; .DetectAndSetDisplaySegment
34; Parameters:
35; DS: BDA segment (zero)
36; Returns:
37; Nothing
38; Corrupts registers:
39; Nothing
40;--------------------------------------------------------------------
41.DetectAndSetDisplaySegment:
42 mov WORD [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition+2], COLOR_TEXT_SEGMENT
43 cmp BYTE [VIDEO_BDA.bMode], MDA_TEXT_MODE
44 jne SHORT .Return
45 sub WORD [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition+2], COLOR_TEXT_SEGMENT - MONO_TEXT_SEGMENT
46.Return:
47 ret
48
49
50;--------------------------------------------------------------------
51; DisplayContext_Push
52; Parameters:
53; Nothing
54; Returns:
55; Nothing
56; Corrupts registers:
57; AX, DI
58;--------------------------------------------------------------------
59ALIGN JUMP_ALIGN
60DisplayContext_Push:
61 mov di, ds ; Backup DS
62 LOAD_BDA_SEGMENT_TO ds, ax
63 pop ax ; Pop return address
64
65 %assign i 0
66 %rep DISPLAY_CONTEXT_size / 2
67 push WORD [VIDEO_BDA.displayContext + i]
68 %assign i i+2
69 %endrep
70
71 mov ds, di ; Restore DS
72 jmp ax
73
74;--------------------------------------------------------------------
75; DisplayContext_Pop
76; Parameters:
77; Nothing
78; Returns:
79; Nothing
80; Corrupts registers:
81; AX, DI
82;--------------------------------------------------------------------
83ALIGN JUMP_ALIGN
84DisplayContext_Pop:
85 mov di, ds ; Backup DS
86 LOAD_BDA_SEGMENT_TO ds, ax
87 pop ax ; Pop return address
88
89 %assign i DISPLAY_CONTEXT_size-2
90 %rep DISPLAY_CONTEXT_size / 2
91 pop WORD [VIDEO_BDA.displayContext + i]
92 %assign i i-2
93 %endrep
94
95 push ax ; Push return address
96 push dx
97 call DisplayContext_SynchronizeToHardware
98 pop dx
99 mov ds, di ; Restore DS
100 ret
101
102
103;--------------------------------------------------------------------
104; DisplayContext_SynchronizeToHardware
105; Parameters:
106; DS: BDA segment (zero)
107; Returns:
108; Nothing
109; Corrupts registers:
110; AX, DX
111;--------------------------------------------------------------------
112ALIGN JUMP_ALIGN
113DisplayContext_SynchronizeToHardware:
114 call DisplayPage_SynchronizeToHardware
115 call DisplayCursor_SynchronizeShapeToHardware
116 jmp DisplayCursor_SynchronizeCoordinatesToHardware
117
118
119;--------------------------------------------------------------------
120; DisplayContext_SetCharacterPointerFromBXAX
121; Parameters:
122; BX:AX: Ptr to destination for next character to output
123; DS: BDA segment (zero)
124; Returns:
125; ES:DI: Pointer that was in DX:AX
126; Corrupts registers:
127; AX
128;--------------------------------------------------------------------
129ALIGN JUMP_ALIGN
130DisplayContext_SetCharacterPointerFromBXAX:
131 mov [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition], ax
132 mov [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition+2], bx
133 xchg di, ax
134 mov es, bx
135 ret
136
137
138;--------------------------------------------------------------------
139; DisplayContext_GetCharacterPointerToBXAX
140; Parameters:
141; DS: BDA segment (zero)
142; Returns:
143; BX:AX: Ptr to destination for next character to output
144; Corrupts registers:
145; Nothing
146;--------------------------------------------------------------------
147ALIGN JUMP_ALIGN
148DisplayContext_GetCharacterPointerToBXAX:
149 mov ax, [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition]
150 mov bx, [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition+2]
151 ret
152
153
154;--------------------------------------------------------------------
155; DisplayContext_SetCharOutputFunctionFromAXwithAttribFlagInDL
156; Parameters:
157; AX: Offset to character output function
158; DL: Attribute Flag
159; DS: BDA segment (zero)
160; Returns:
161; Nothing
162; Corrupts registers:
163; Nothing
164;--------------------------------------------------------------------
165ALIGN JUMP_ALIGN
166DisplayContext_SetCharOutputFunctionFromAXwithAttribFlagInDL:
167 mov [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fnCharOut], ax
168 and BYTE [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bFlags], ~FLG_CONTEXT_ATTRIBUTES
169 mov al, dl
170 and al, FLG_CONTEXT_ATTRIBUTES
171 or [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bFlags], al
172 ret
173
174
175;--------------------------------------------------------------------
176; DisplayContext_SetCharacterAttributeFromAL
177; Parameters:
178; AL: Character attribute
179; DS: BDA segment (zero)
180; Returns:
181; Nothing
182; Corrupts registers:
183; Nothing
184;--------------------------------------------------------------------
185ALIGN JUMP_ALIGN
186DisplayContext_SetCharacterAttributeFromAL:
187 mov [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bAttribute], al
188 ret
189
190
191;--------------------------------------------------------------------
192; DisplayContext_SetCharacterOutputParameterFromAX
193; Parameters:
194; AX: Parameter for Character Output function
195; DS: BDA segment (zero)
196; Returns:
197; Nothing
198; Corrupts registers:
199; Nothing
200;--------------------------------------------------------------------
201ALIGN JUMP_ALIGN
202DisplayContext_SetCharacterOutputParameterFromAX:
203 mov [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.wCharOutParam], ax
204 ret
205
206;--------------------------------------------------------------------
207; DisplayContext_GetCharacterOutputParameterToDX
208; Parameters:
209; DS: BDA segment (zero)
210; Returns:
211; DX: User parameter for Character Output function
212; Corrupts registers:
213; Nothing
214;--------------------------------------------------------------------
215ALIGN JUMP_ALIGN
216DisplayContext_GetCharacterOutputParameterToDX:
217 mov dx, [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.wCharOutParam]
218 ret
219
220
221;--------------------------------------------------------------------
222; DisplayContext_GetCharacterOffsetToAXfromByteOffsetInAX
223; Parameters:
224; AX: Offset in bytes from some character to another
225; DS: BDA segment (zero)
226; Returns:
227; AX: Offset in characters from some character to another
228; Corrupts registers:
229; Nothing
230;--------------------------------------------------------------------
231ALIGN JUMP_ALIGN
232DisplayContext_GetCharacterOffsetToAXfromByteOffsetInAX:
233 test BYTE [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bFlags], FLG_CONTEXT_ATTRIBUTES
234 jz SHORT ReturnOffsetInAX
235 sar ax, 1 ; BYTE count to WORD count
236 ret
237
238;--------------------------------------------------------------------
239; DisplayContext_GetByteOffsetToAXfromCharacterOffsetInAX
240; Parameters:
241; AX: Offset in characters from some character to another
242; DS: BDA segment (zero)
243; Returns:
244; AX: Offset in bytes from some character to another
245; Corrupts registers:
246; Nothing
247;--------------------------------------------------------------------
248ALIGN JUMP_ALIGN
249DisplayContext_GetByteOffsetToAXfromCharacterOffsetInAX:
250 test BYTE [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bFlags], FLG_CONTEXT_ATTRIBUTES
251 jz SHORT ReturnOffsetInAX
252 sal ax, 1 ; WORD count to BYTE count
253ALIGN JUMP_ALIGN, ret
254ReturnOffsetInAX:
255 ret
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