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Text File | 2002-09-30 | 18.0 KB | 362 lines

Mouse driver services --------------------- Functions implemented in CTMOUSE: INT 33/0000 - MS MOUSE - Reset driver and read status INT 33/0001 - MS MOUSE v1.0+ - Show mouse cursor INT 33/0002 - MS MOUSE v1.0+ - Hide mouse cursor INT 33/0003 - MS MOUSE v1.0+ - Get cursor position and buttons status INT 33/0004 - MS MOUSE v1.0+ - Position mouse cursor INT 33/0005 - MS MOUSE v1.0+ - Get button press data INT 33/0006 - MS MOUSE v1.0+ - Get button release data INT 33/0007 - MS MOUSE v1.0+ - Set horizontal cursor range INT 33/0008 - MS MOUSE v1.0+ - Set vertical cursor range INT 33/0009 - MS MOUSE v3.0+ - Define graphics cursor INT 33/000A - MS MOUSE v3.0+ - Define text cursor INT 33/000B - MS MOUSE v1.0+ - Get motion counters INT 33/000C - MS MOUSE v1.0+ - Define User Interrupt Routine INT 33/000F - MS MOUSE v1.0+ - Set mickeys/pixels ratios INT 33/0010 - MS MOUSE v1.0+ - Define screen region for updating INT 33/0014 - MS MOUSE v3.0+ - Exchange User Interrupt Routines INT 33/0015 - MS MOUSE v6.0+ - Get driver storage requirements INT 33/0016 - MS MOUSE v6.0+ - Save driver state INT 33/0017 - MS MOUSE v6.0+ - Restore driver state INT 33/001A - MS MOUSE v6.0+ - Set mouse sensitivity INT 33/001B - MS MOUSE v6.0+ - Get mouse sensitivity INT 33/001E - MS MOUSE v6.0+ - Get display page INT 33/001F - MS MOUSE v6.0+ - Disable mouse driver INT 33/0020 - MS MOUSE v6.0+ - Enable mouse driver INT 33/0021 - MS MOUSE v6.0+ - Software reset INT 33/0023 - MS MOUSE v6.0+ - Get language for messages INT 33/0024 - MS MOUSE v6.26+ - Get software version, mouse type and IRQ INT 33/0026 - MS MOUSE v6.26+ - Get maximum virtual screen coordinates INT 33/0027 - MS MOUSE v7.01+ - Get screen/cursor masks and mickey counters INT 33/002A - MS MOUSE v7.02+ - Get cursor hot spot INT 33/0031 - MS MOUSE v7.05+ - Get current virtual cursor coordinates INT 33/0032 - MS MOUSE v7.05+ - Get supported advanced functions flag INT 33/004D - MS MOUSE - Get pointer to copyright string INT 33/006D - MS MOUSE - Get pointer to version Video functions implemented in CTMOUSE: INT 10/F0 - EGA Register Interface Library - Read one register INT 10/F1 - EGA Register Interface Library - Write one register INT 10/F2 - EGA Register Interface Library - Read register range INT 10/F3 - EGA Register Interface Library - Write register range INT 10/F4 - EGA Register Interface Library - Read register set INT 10/F5 - EGA Register Interface Library - Write register set INT 10/F6 - EGA Register Interface Library - Revert registers to default INT 10/F7 - EGA Register Interface Library - Define registers default INT 10/FA - EGA Register Interface Library - Interrogate driver The following functions are not implemented but they don't return anything and can be counted as implemented: INT 33/000D - MS MOUSE v1.0+ - Light pen emulation ON INT 33/000E - MS MOUSE v1.0+ - Light pen emulation OFF INT 33/0013 - MS MOUSE v5.0+ - Define double-speed threshold INT 33/001C - MS MOUSE v6.0+ - Set interrupt rate INT 33/001D - MS MOUSE v6.0+ - Set display page INT 33/0022 - MS MOUSE v6.0+ - Set language for messages The following functions are not implemented: INT 10/04 - VIDEO - Get light pen position (except VGA) INT 33/0012 - MS MOUSE - Set large graphics cursor block INT 33/0018 - MS MOUSE v6.0+ - Set alternate User Interrupt Routine INT 33/0019 - MS MOUSE v6.0+ - Get alternate User Interrupt Routine INT 33/0025 - MS MOUSE v6.26+ - Get general driver information INT 33/0028 - MS MOUSE v7.0+ - Set video mode INT 33/0029 - MS MOUSE v7.0+ - Enumerate video modes INT 33/002B - MS MOUSE v7.0+ - Load acceleration profiles INT 33/002C - MS MOUSE v7.0+ - Get acceleration profiles INT 33/002D - MS MOUSE v7.0+ - Select acceleration profile INT 33/002E - MS MOUSE v8.10+ - Set acceleration profile names INT 33/002F - MS MOUSE v7.02+ - Mouse hardware reset INT 33/0030 - MS MOUSE v7.04+ - Get/Set BallPoint information INT 33/0033 - MS MOUSE v7.05+ - Get switch settings and acceleration profile data INT 33/0034 - MS MOUSE v8.0+ - Get initialization file INT 33/0035 - MS MOUSE v8.10+ - LCD screen large pointer support Details of driver operation --------------------------- CTMOUSE displays the cursor only in standard video modes of CGA, EGA and VGA; Hercules Graphics/InColor Card or SVGA/VESA extended video modes are not supported but an application can display the cursor by itself in a user interrupt routine (may be installed by INT 33/000C function) or when idle. Remember to remove calls to INT 33/0001 (Show cursor) and define cursor movement limits (INT 33/0007 and INT 33/0008). Some applications call INT 33/0001 (Show cursor), INT 33/0009 (Define graphics cursor) and INT 33/000A (Define text cursor) in loops. To prevent cursor flickering INT 33/0001 function redraws cursor only if it was hidden before and INT 33/0004 (Position cursor), INT 33/0009 and INT 33/000A functions redraw cursor only if its position or pattern has changed. Unlike many other mouse drivers, CTMOUSE doesn't require call INT 33/0002 (Hide cursor) or INT 33/0010 (Define region for updating) before writing to the screen in text mode because screen under cursor isn't restored if cursor is overwritten. However CTMOUSE can't correct all cases of cursor overwriting: when a character is written at the cursor position without an attribute, (through INT 10/0E (Teletype output) or INT 21), then it gets the cursor's attribute. Also, if cursor is overwritten by character with attribute which is equal to cursor's character/attribute then CTMOUSE restores the old character/attribute. Unlike Microsoft's specification, CTMOUSE always displays cursor on the active video page and doesn't require call INT 33/001D (Set display page) at all; this function is, anyway, a dummy. Below is a table of virtual screen size, cursor movement granularity and minimum/maximum size of region on the screen, occupied by cursor (actual for INT 33/0010) for each video mode: min max mode screen cell shape shape *0 640x200 16x8 16x8 16x8 *1 640x200 16x8 16x8 16x8 *2 640x200 8x8 8x8 8x8 *3 640x200 8x8 8x8 8x8 4 640x200 2x1 16x16 24x16 5 640x200 2x1 16x16 24x16 6 640x200 1x1 16x16 24x16 *7 640x200 8x8 8x8 8x8 0Dh 640x200 2x1 32x16 48x16 0Eh 640x200 1x1 16x16 24x16 0Fh 640x350 1x1 16x16 24x16 10h 640x350 1x1 16x16 24x16 11h 640x480 1x1 16x16 24x16 12h 640x480 1x1 16x16 24x16 13h 640x200 2x1 32x16 32x16 other 640x200 1x1 - - * for text modes, the virtual screen size is given for standard screen sizes 40x25 and 80x25; for other screen sizes the corresponding virtual screen size is changed accordingly. In standard text modes, CTMOUSE supports any screen size beside 40x25 and 80x25. It sets virtual screen size as [screen width in characters]*8 by [screen height in characters]*8 (except video modes 0-1, where width is multiplied by 16) each time when the video mode or the screen size is changed or INT 33/0000 (Reset driver), INT 33/0020 (Enable driver) or INT 33/0021 (Software reset) are called. CTMOUSE intercepts only INT 10/0 (Set video mode), INT 10/111x (Load and activate font) and INT 10/4F02 (Set VESA/SVGA video mode) functions. If screen size in text mode changed by other functions like INT 10/1Ch (VGA state save/restore) or by direct hardware programming, then INT 33/0000 (Reset driver), INT 33/0020 (Enable driver) or INT 33/0021 (Software reset) must be called to renew virtual screen size. If INT 33/0020 only is called then INT 33/0007 (Set horizontal range) and INT 33/0008 (Set vertical range) also should be called with min=0 and max=[8*screen width-1,8*screen height-1] to enable the complete screen for cursor movement. INT 33/0007 (Set horizontal range) and INT 33/0008 (Set vertical range) functions setup cursor movement area but cursor will be seen on the screen only in standard video modes and when cursor shape intersects with virtual screen coordinates. All driver's coordinates (ranges, cursor positions, regions) interpreted as signed values, also as cursor hot spot or mickey counts. Notes for mouse driver services ------------------------------- For bitmapped graphics modes 4-6 and 0Dh-12h a peculiarity of INT 33/0010 (Define region for updating) function should be noted: horizontal cursor position is always aligned by modulo 8 or 16 and cursor occupies 24 or 48 positions, unlike mode 13h, where start position is unchanged and cursor occupies 32 positions; i.e. for left limit L and right limit R in modes 4-6, 0Eh-12h cursor will be hidden between (L-L%8)-16 and [R/8+1]*8-1 positions, in mode 0Dh cursor will be hidden between (L-L%16)-32 and [R/16+1]*16-1 positions and in mode 13h cursor will be hidden between L-32 and R positions. To set update region via INT 33/0010 in terms of character positions you must compute arguments as CX=left*W, DX=top*8, SI=(right+1)*W-1 and DI=(bottom+1)*W-1, where W=16 for modes 0-1, 4-5, 0Dh and 13h and W=8 for all other modes. Size of buffer, required to save driver state by INT 33/0016, in CTMOUSE is less than 180 bytes; exact buffer size is returned by INT 33/0015 (Get driver storage requirements). INT 33/0016 (Save driver state) and INT 33/0017 (Restore driver state) functions save and restore user defined variables (mickeys per 8 pixels, user interrupt routine call mask and address), cursor definition (cursor type, text and graphics shape, visibility, position, ranges and update region) and mouse access state (mickeys mouse moved, buttons press and release status since last access). These functions don't affect driver state (disabled flag, resolution level), mouse definition (mouse type, buttons count, IO address and interrupt), video mode definition (maximum virtual screen coordinates, EGA RIL register values) and dummy variables (lightpen emulation status and double speed threshold). When the video mode after INT 10/0 or INT 10/4F02 or screen size after INT 10/111x is changed, CTMOUSE hides cursor so that it can be shown by next INT 33/0001, recalculates screen sizes, sets cursor ranges to virtual screen sizes and centers cursor. INT 33/0000 (Reset driver) and INT 33/0021 (Software reset) functions hide cursor (so that it can be shown by next INT 33/0001), recalculate screen sizes, set cursor ranges to screen sizes, center cursor and clear mickey counts, user interrupt routine call mask and button press/release data. In addition, horizontal mickeys per 8 pixels ratio is set to 8, vertical mickeys per 8 pixels ratio is set to 16, software text mode cursor is set with reverse video shape (screen mask 77FFh, cursor mask 7700h) and graphics mode cursor shape is set to arrow with zero hot spot. INT 33/001F (Disable driver) function hides cursor so that it can be shown by next INT 33/0001, disables mouse, restores IRQ interrupt (for serial mouse) and returns in ES:BX the old INT 33 interrupt handler address. If INT 33 or INT 10 interrupt was intercepted by another program then on exit AX will contain -1, else if INT 10 interrupt handler was not restored yet then it will be restored. INT 33/0020 (Enable driver) function installs IRQ handler (if serial mouse is active) and INT 10 handler (if it is not yet installed), enables mouse interrupts, recalculates screen sizes, sets cursor ranges to screen sizes and centers cursor. CTMOUSE supports INT 33/0022 and 0023 (Set/get language for messages) functions, but only for English. When you have to deal with RIL, keep in mind that RIL is unprotected from wrong user input - RIL functions should be called only in standard video modes and on EGA or later video adapters, and RIL doesn't check if group index, register number or count of registers are valid. Asynchronous execution and User Interrupt Routine (UIR) ------------------------------------------------------ UIR installed via INT 33/000C (Define UIR) or INT 33/0014 (Exchange UIRs) must use far RET (not IRET) for return and it is not required to keep any register value except SS:SP. Mouse interrupt handler (IH) redraws cursor on the screen only when the called UIR returns to IH. If new mouse events occur before UIR returns to IH, then IH will not redraw cursor and call UIR again (i.e. UIR is not required to be re-enterable). However, mouse events themselves will be parsed and reflected in driver state, so driver state (cursor position, buttons state) may be changed before UIR returns. Therefore, UIR should be aware of a possible difference between initial arguments and values returned by driver functions. Driver functions will not hide or redraw cursor if they are called while cursor hidding or drawing routines in the driver are already working. This means that cursor will not be redrawn by requests from UIR or any other general purpose hardware interrupt handler, if they are executed while cursor redrawing was in progress (this will look like cursor on the screen freezes). But hidding or drawing routines will be called again when they finish their first request if new request comes in from interrupt handlers while they are working. When bit 0 ("call if mouse moves") is set in the UIR call mask then UIR will be called when any mickey count is changed. Note: cursor position usually changes less often than mickey counts because mickeys per 8 pixels ratios can reduce mickeys change to zero and cursor position change can be hidden by granulation (in text modes cursor positions are always factor of 8 or 16; in some graphics modes X cursor positions are always factor of two). Used BIOS variables ------------------- 0:449h bits 0-6 used to determine the current video mode (when driver enabled by INT 33/0020 or video mode changed) 0:44Ah screen width in text columns (used to compute offset in video memory in text video modes) 0:44Eh offset in video segment of active video memory page 0:462h current video page (returned by INT 33/001E) 0:463h used to compute CRTC base and Feature Control video ports addresses (when driver enabled by INT 33/0020 or video mode changed) 0:46Ch timer used in mouse detection routine to make timing 0:487h bits 5-6 used to determine RAM size on video adapter (when driver enabled by INT 33/0020 or video mode changed) 0:488h bits 0-3 used to get video configuration switches (when driver enabled by INT 33/0020 or video mode changed) 0:4A8h used to get default video registers values for RIL (when driver enabled by INT 33/0020 or video mode changed) Used interrupts --------------- INT 10/01 setup text-mode hardware cursor shape, when hardware cursor selected INT 10/1A00 get DCC to check VGA presence INT 15/C200 enable/disable PS/2 pointing device INT 15/C203 set resolution of PS/2 pointing device [when PS/2 checking] INT 15/C205 initialize PS/2 pointing device [when PS/2 checking] INT 15/C207 set handler for PS/2 pointing device INT 21/09 output all strings to standard output INT 21/25 install interrupt handlers for INT 33, INT 10 and IRQ handler, also restore those interrupts INT 21/26 create new PSP for driver image in the UMB [when trying to install driver high] INT 21/31 remain TSR when driver not copied to other UMB segment INT 21/35 save old INT 33, INT 10 and IRQ handlers addresses INT 21/48 allocate UMB memory [when trying to install driver high] INT 21/49 free memory used by environment and by unloaded TSR INT 21/4C terminate program with nonzero errorlevel if some error found or with zero errorlevel when no errors INT 21/58 modify memory allocation strategy [when trying to install driver high] INT 2F/4310 get XMS driver entry [when trying to install driver high] INT 33/001F disable previous mouse driver, if one is present INT 33/0020 enable previous mouse driver after unloading CuteMouse INT 33/004D check if installed driver is CuteMouse Techniques used --------------- 1. Two writes to adjacent I/O ports are combined into one write "out dx,ax" (used for most video registers, divisor latch of COM port, etc). 2. For interrupt handler's address comparision only segment of address is used, because usually different programs reside in different segments and no one program is pointed to by zero segment. 3. CuteMouse uses a lot of self-modifying code and many variables are placed in the code instructions; most of code modification is grouped in the setupdriver and softreset_21 procedures. 4. To use free part of PSP and thus minimize memory footprint, CuteMouse source includes corresponding "ORG" statement before uninitialized variables, for which only offsets are computed and no data is generated. Note: in TASM 3.1, a structure instance with "DUP(?)" generates data (fixed in TASM 4.1), so buttpress and buttrelease arrays are defined without "DUP" as series of BUTTLASTSTATE structure insertions instead. 5. CuteMouse is written using TASM and makes use some of TASM features: for example, multiple "push" and "pop" in one line ("push ax bx") and shifts with an immediate value >1 ("shl ax,2"), which are converted into several opcodes valid for 8086/8088 CPUs (i.e. for shifts, TASM simply duplicates them - "shl ax,1/shl ax,1"), because there is no ".186" or higher statement. 6. Often instructions with shorter opcode but slightly different behavior than assumed instruction are used to minimize code; each such use is marked by "OPTIMIZE" comment. In addition, instructions for which functions are performed by previous code remain in the source as comments; this is done for greater readability and to ease code carrying. 7. To ease code pipelining in CPU, instructions which manipulate common registers or other resources are interspersed with other kinds of instructions whenever possible. For example: mov ax,cx mov ax,cx add ax,bx neg dx neg dx add ax,bx here second variant is preferred.