source: xtideuniversalbios/trunk/Assembly_Library/Src/Keyboard/Keyboard.asm@ 76

Last change on this file since 76 was 54, checked in by Tomi Tilli, 14 years ago

Changes to Assembly Library:
Drive selection moved to own dialog from File Dialog.
File Dialog now displays loading text for better usability in slow systems.
Moved some functions from Memory.asm to new Registers.asm.
File size: 7.9 KB
Line 
1; File name : Keyboard.asm
2; Project name : Assembly Library
3; Created date : 5.7.2010
4; Last update : 24.10.2010
5; Author : Tomi Tilli
6; Description : Functions for managing keyboard.
7
8BUFFER_SIZE_FOR_WORD_INPUT EQU 6 ; 5 chars + NULL
9
10; Section containing code
11SECTION .text
12
13;--------------------------------------------------------------------
14; Reads user inputted word.
15; Function returns when ENTER or ESC will be pressed.
16;
17; Keyboard_ReadUserInputtedWordWhilePrinting
18; Parameters
19; BX: Numeric base (10 or 16)
20; Returns:
21; AX: User inputted word
22; ZF: Set if user cancellation
23; Corrupts registers:
24; DX
25;--------------------------------------------------------------------
26ALIGN JUMP_ALIGN
27Keyboard_ReadUserInputtedWordWhilePrinting:
28 push ds
29 push si
30 push cx
31
32 mov cx, BUFFER_SIZE_FOR_WORD_INPUT
33 call Memory_ReserveCXbytesFromStackToDSSI
34
35 call Char_GetFilterFunctionToDXforNumericBaseInBX
36 call Registers_ExchangeDSSIwithESDI
37 call Keyboard_ReadUserInputtedStringToESDIWhilePrinting
38 call Registers_ExchangeDSSIwithESDI ; Does not modify FLAGS
39 jz SHORT .CancelledByUser
40
41 call String_ConvertWordToAXfromStringInDSSIwithBaseInBX
42.CancelledByUser:
43 add sp, BYTE BUFFER_SIZE_FOR_WORD_INPUT
44 test cx, cx ; Set ZF if string length is zero
45 pop cx
46 pop si
47 pop ds
48 ret
49
50
51;--------------------------------------------------------------------
52; Reads user inputted string to buffer. Character filter is
53; supported to ignore unwanted characters.
54; Function returns when ENTER or ESC will be pressed.
55;
56; Keyboard_ReadUserInputtedStringToESDIWhilePrinting
57; Parameters:
58; CX: Buffer size (with NULL)
59; ES:DI: Ptr to destination buffer
60; CS:DX: Ptr to character filter function:
61; Parameters:
62; AL: Character inputted by user
63; Returns:
64; CF: Set if character is accepted
65; Cleared if character is rejected
66; Corrupts registers:
67; Nothing
68; Returns:
69; CX: String length in characters (without NULL)
70; ZF: Set if user cancellation
71; Corrupts registers:
72; AX
73;--------------------------------------------------------------------
74ALIGN JUMP_ALIGN
75Keyboard_ReadUserInputtedStringToESDIWhilePrinting:
76 push di
77 push si
78 push bx
79 call .PrepareDisplayContextForKeyboardInput
80 jcxz .ReturnAfterUpdatingZF
81
82 xor bx, bx ; Zero character counter
83 dec cx ; Decrement buffer size for NULL
84 cld
85ALIGN JUMP_ALIGN
86.GetCharacterFromUser:
87 call Keyboard_GetKeystrokeToAXandWaitIfNecessary ; Get ASCII to AL
88 call .ProcessControlCharacter
89 jz SHORT .TerminateStringWithNULL
90 jc SHORT .PlayBellForRejectedCharacter
91 call dx ; Filter character
92 jnc SHORT .PlayBellForRejectedCharacter
93 inc bx ; Increment number of characters stored
94 stosb ; Store from AL to ES:DI
95 call Keyboard_PrintInputtedCharacter
96 loop .GetCharacterFromUser
97.PlayBellForRejectedCharacter:
98 cmp al, BS ; No bell for backspace
99 je SHORT .GetCharacterFromUser
100 call Keyboard_PlayBellForUnwantedKeystroke
101 jmp SHORT .GetCharacterFromUser
102
103.TerminateStringWithNULL:
104 stosb ; Terminate string with NULL
105 mov cx, bx ; String length now in CX
106
107.ReturnAfterUpdatingZF:
108 CALL_DISPLAY_LIBRARY PopDisplayContext
109 test cx, cx ; Clear or set ZF
110 pop bx
111 pop si
112 pop di
113 ret
114
115;--------------------------------------------------------------------
116; .PrepareDisplayContextForKeyboardInput
117; Parameters:
118; Nothing
119; Returns:
120; Nothing (Display context pushed to stack)
121; Corrupts registers:
122; AX, BX, SI
123;--------------------------------------------------------------------
124ALIGN JUMP_ALIGN
125.PrepareDisplayContextForKeyboardInput:
126 pop bx ; Pop return address to BX
127 mov si, di
128
129 CALL_DISPLAY_LIBRARY PushDisplayContext
130 mov ax, CURSOR_NORMAL
131 CALL_DISPLAY_LIBRARY SetCursorShapeFromAX
132 CALL_DISPLAY_LIBRARY SynchronizeDisplayContextToHardware
133
134 mov di, si
135 jmp bx
136
137
138;--------------------------------------------------------------------
139; .ProcessControlCharacter
140; Parameters:
141; AL: Character inputted by user
142; CX: Number of bytes left in buffer
143; BX: Total number of characters inputted
144; ES:DI: Ptr where to store next character
145; Returns:
146; AL: Character inputted by user or NULL if end of input
147; BX: Cleared if user cancellation
148; ZF: Set if user has ended or cancelled key input
149; CF: Set if character is rejected
150; Corrupts registers:
151; AH
152;--------------------------------------------------------------------
153ALIGN JUMP_ALIGN
154.ProcessControlCharacter:
155 cmp al, CR ; ENTER to terminate string?
156 je SHORT .EndCharacterInput
157 cmp al, ESC ; Cancel input?
158 je SHORT .CancelCharacterInput
159 cmp al, BS ; Backspace?
160 je SHORT .Backspace
161 jcxz .RejectCharacter
162 test al, al ; Clear ZF and CF
163 ret
164
165.Backspace:
166 test bx, bx ; At the beginning?
167 jz SHORT .RejectCharacter
168 inc cx ; Increment bytes left
169 dec bx ; Decrement characters inputted
170 dec di
171 call Keyboard_PrintBackspace
172 mov al, BS ; Restore character
173.RejectCharacter:
174 test al, al ; Clear ZF...
175 stc ; ...and set CF
176 ret
177
178.CancelCharacterInput:
179 xor bx, bx
180.EndCharacterInput:
181 xor al, al ; Set ZF and clear CF
182 ret
183
184
185;--------------------------------------------------------------------
186; Keyboard_PrintBackspace
187; Parameters:
188; Nothing
189; Returns:
190; Nothing
191; Corrupts registers:
192; AX
193;--------------------------------------------------------------------
194ALIGN JUMP_ALIGN
195Keyboard_PrintBackspace:
196 mov al, BS
197 call Keyboard_PrintInputtedCharacter
198 mov al, ' '
199 call Keyboard_PrintInputtedCharacter
200 mov al, BS
201 jmp SHORT Keyboard_PrintInputtedCharacter
202
203
204;--------------------------------------------------------------------
205; Keyboard_PlayBellForUnwantedKeystroke
206; Parameters:
207; Nothing
208; Returns:
209; Nothing
210; Corrupts registers:
211; AX
212;--------------------------------------------------------------------
213ALIGN JUMP_ALIGN
214Keyboard_PlayBellForUnwantedKeystroke:
215 mov al, BELL
216 ; Fall to Keyboard_PrintInputtedCharacter
217
218;--------------------------------------------------------------------
219; Keyboard_PrintInputtedCharacter
220; Parameters:
221; AL: Character inputted by user
222; Returns:
223; Nothing
224; Corrupts registers:
225; AX
226;--------------------------------------------------------------------
227ALIGN JUMP_ALIGN
228Keyboard_PrintInputtedCharacter:
229 push di
230 CALL_DISPLAY_LIBRARY PrintCharacterFromAL
231 CALL_DISPLAY_LIBRARY SynchronizeDisplayContextToHardware ; Hardware cursor
232 pop di
233 ret
234
235
236;--------------------------------------------------------------------
237; Keyboard_RemoveAllKeystrokesFromBuffer
238; Parameters:
239; Nothing
240; Returns:
241; Nothing
242; Corrupts registers:
243; AX
244;--------------------------------------------------------------------
245ALIGN JUMP_ALIGN
246Keyboard_RemoveAllKeystrokesFromBuffer:
247 call Keyboard_GetKeystrokeToAX
248 jnz SHORT Keyboard_RemoveAllKeystrokesFromBuffer
249 ret
250
251
252;--------------------------------------------------------------------
253; Keyboard_GetKeystrokeToAX
254; Keyboard_GetKeystrokeToAXandLeaveItToBuffer
255; Keyboard_GetKeystrokeToAXandWaitIfNecessary
256; Parameters:
257; Nothing
258; Returns:
259; AL: ASCII character (if keystroke available)
260; AH: BIOS scan code (if keystroke available)
261; ZF: Set if no keystroke available
262; Cleared if keystroke available
263; Corrupts registers:
264; Nothing
265;--------------------------------------------------------------------
266ALIGN JUMP_ALIGN
267Keyboard_GetKeystrokeToAX:
268 call Keyboard_GetKeystrokeToAXandLeaveItToBuffer
269 jnz SHORT Keyboard_GetKeystrokeToAXandWaitIfNecessary
270 ret
271ALIGN JUMP_ALIGN
272Keyboard_GetKeystrokeToAXandLeaveItToBuffer:
273 mov ah, CHECK_FOR_KEYSTROKE
274 int BIOS_KEYBOARD_INTERRUPT_16h
275 ret
276ALIGN JUMP_ALIGN
277Keyboard_GetKeystrokeToAXandWaitIfNecessary:
278 xor ah, ah ; GET_KEYSTROKE
279 int BIOS_KEYBOARD_INTERRUPT_16h
280 test ax, ax ; Clear ZF
281 ret
Note: See TracBrowser for help on using the repository browser.