winvram Device Specification

The Video Ram

The video ram uses 4 Byte (one TETRA) for each pixel: II RR GG BB The high order byte II is ignored, the next byte RR specifies the red value in the range 0 (black) to 255 (full red), then GG the green and finally in the low order byte BB the blue value - again in the range 0 to 255.

The first TETRA belongs to the top left pixel. The second TETRA to the next pixel just to the right of it. Line by line from top to bottom, each TETRA in memory belongs to one pixel. The size of the video ram depends on the configuration. The default gives a frame buffer 640 pixel wide and 480 Pixel high. Other sizes are possible. It is possible to configure the visible size smaller than the size of the frame buffer; this leaves video ram, that is not visible (off screen video ram). It can be used to store bitmaps. These can be transfered to the visible part very fast using the GPU.

The Mouse device

The Mouse device uses 16 Byte that are read-only.

Index Name Description
00-01 buttons The value indicates which buttons are down when the event happens:

0x01 = MK_LBUTTON The left mouse button is down.
0x10 = MK_MBUTTON The middle mouse button is down.
0x02 = MK_RBUTTON The right mouse button is down.
0x04 = MK_SHIFT The SHIFT key is down.
0x08 = MK_CONTROL The CTRL key is down.

02-03 event The event bits use MK_LBUTTON, MK_MBUTTON, and MK_RBUTTON to indicate the button. Bit 0x04 (MK_SHIFT) is 1 for a down event, and 0 for an up event. If the down event is a double-click, the bit 0x08 (MK_CONTROL) is set in addition. A Mouse Move event is indicated by bit 0x80.
04-05 x The x position where the event happens
06-07 y The y position where the event happens
08-11 unused
12-13 cx the current x position of the mouse.
14-15 cy the current y position of the mouse.

The Graphics Processing Unit GPU

The GPU uses 56 Byte as follows:

Index Name Description
0x00 command/status see below.
0x01-0x03 command aux see below.
0x04-0x05 x new x position
0x06-0x07 y new y position
0x08-0x09 w width
0x0a-0x0b h height
0x0c-0x0d cur_x current x position
0x0e-0x0f cur_y current y position
0x10-0x17 bba bit block address
0x18 - ignored
0x19 tbr text background color red
0x1a tbg text background color green
0x1b tbb text background color blue
0x1c - ignored
0x1d tfr text foreground color red
0x1e tfg text foreground color green
0x1f tfb text foreground color blue
0x20 - ignored
0x21 fr fill color red
0x22 fg fill color green
0x23 fb fill color blue
0x24 - ignored
0x25 lr line color red
0x26 lg line color green
0x27 lb line color blue
0x28-0x29 cw character width
0x2a-0x2b ch character height
0x2c-0x2f - unused
0x30-0x31 fw frame width
0x32-0x33 fh frame height
0x34-0x35 sh screen width
0x36-0x37 sh screen height

Index	Name	Description
0x00	command/status	see below.
0x01-0x03	command aux	see below.
0x04-0x05	x	new x position
0x06-0x07	y	new y position
0x08-0x09	w	width
0x0a-0x0b	h	height
0x0c-0x0d	cur_x	current x position
0x0e-0x0f	cur_y	current y position
0x10-0x17	bba	bit block address
0x18	-	ignored
0x19	tbr	text background color red
0x1a	tbg	text background color green
0x1b	tbb	text background color blue
0x1c	-	ignored
0x1d	tfr	text foreground color red
0x1e	tfg	text foreground color green
0x1f	tfb	text foreground color blue
0x20	-	ignored
0x21	fr	fill color red
0x22	fg	fill color green
0x23	fb	fill color blue
0x24	-	ignored
0x25	lr	line color red
0x26	lg	line color green
0x27	lb	line color blue
0x28-0x29	cw	character width
0x2a-0x2b	ch	character height
0x2c-0x2f	-	unused
0x30-0x31	fw	frame width
0x32-0x33	fh	frame height
0x34-0x35	sh	screen width
0x36-0x37	sh	screen height

The first 4 Byte (0-4) contain the command. Writing any of these bytes will trigger the execution of the command. The command may be split into a command number (byte 0) and some auxiliary information (1-3). The command number (byte 0) also serves as status byte. The most significant bit is an error indicator. Therefore reading a negativ status byte, indicates that an error has occured during the last operation. Reading the status byte will reset the error indicator. So reading the status byte twice will return a nonnegative value the second time (unless a new error has occured between the first and the second read). A zero status byte indicates that the GPU is idle and ready to receive new commands. A positive status byte indicates that the GPU is bussy. The values are device dependent. While the GPU is bussy, the effect of writing to the command byte is unspecified. You can, however, write to (or read from) all the other GPU registers. The values in the other registers will be used only when a GPU command starts executing.

Most commands require a position. The coordinates are either taken from Bytes 4,5 (x) and 6,7 (y) or from Bytes c,d (cur_x) and e,f (cur_y) (the current position). If appropriate, executing a command will update the values cur_x and cur_y to make the current position work like a cursor.

Bit Block transfers from/to non graphic memory need a physical target address. The address goes in the third OCTA, the bit block address (bba).

Some commands require, in addition, color information (Drawing of Text, Lines and Rectangles) this information comes in the fourth and fifth OCTA.

Commands that need new x, y information would primarily use byte 4 to 7. Alternatively the current x,y can be used. Width and height information can be provided in bytes 8, 9 (w) and 0xa, 0xb (w).

The sixth and seventh OCTA are read only. They provide information on the size of the system font, the frame size and the visible part of it.

Commands

command == 0 Do Nothing

command == 1 Write Character

Write the character contained in the low byte of command aux (ASCII) to the current position given in cur_x and cur_y using the system font. Update cur_x and cur_y for the next character. Handle newline (0x0A) by moving cur_x, cur_y to the beginning of the next line and carriage return (0x0D) by moving cur_x, cur_y to the beginning of the current line. Scroll up the screen, if a newline happens to be in the last line of the screen.

command == 2 Draw Rectangle

Draw a filled Rectangle using the fill color, using the x, y position as top left and w,h as the size of the rectangle. No update of the position occurs.

command == 3 Draw Line

Draw a line, using the current line color, from the cur_x, cur_y position to the new x, y position. The new x, y will then replace the current position cur_x, cur_y to support drawing joint lines. If command aux is zero, the default line width is used (usually 1 pixel). If command aux is not zero, it will be used as the line width in pixel.

command == 4 Bit Block Transfer

Transfers a rectangular block of pixels from one part of the video ram to another part of the video ram. The new position x,y is the top left coordinate of the source. The current position cur_x, cur_y is the top left coordinate of the destination; the width and height values w, h define the size of the destination rectangle. Clipping (if needed) occurs on the destination rectangle. The command aux value is used for the raster mode used in a windows Bitblt Function. the following values are defined:

Name Value Operation
SRCCOPY 0xCC0020 dest = source
SRCPAINT 0xEE0086 dest = source OR dest
SRCAND 0x8800C6 dest = source AND dest
SRCINVERT 0x660046 dest = source XOR dest
SRCERASE 0x440328 dest = source AND (NOT dest )
NOTSRCCOPY 0x330008 dest = (NOT source)
NOTSRCERASE 0x1100A6 dest = (NOT src) AND (NOT dest)
MERGECOPY 0xC000CA dest = (source AND pattern)
MERGEPAINT 0xBB0226 dest = (NOT source) OR dest
PATCOPY 0xF00021 dest = pattern
PATPAINT 0xFB0A09 dest = DPSnoo
PATINVERT 0x5A0049 dest = pattern XOR dest
DSTINVERT 0x550009 dest = (NOT dest)
BLACKNESS 0x000042 dest = BLACK
WHITENESS 0xFF0062 dest = WHITE

Name	Value	Operation
SRCCOPY	0xCC0020	dest = source
SRCPAINT	0xEE0086	dest = source OR dest
SRCAND	0x8800C6	dest = source AND dest
SRCINVERT	0x660046	dest = source XOR dest
SRCERASE	0x440328	dest = source AND (NOT dest )
NOTSRCCOPY	0x330008	dest = (NOT source)
NOTSRCERASE	0x1100A6	dest = (NOT src) AND (NOT dest)
MERGECOPY	0xC000CA	dest = (source AND pattern)
MERGEPAINT	0xBB0226	dest = (NOT source) OR dest
PATCOPY	0xF00021	dest = pattern
PATPAINT	0xFB0A09	dest = DPSnoo
PATINVERT	0x5A0049	dest = pattern XOR dest
DSTINVERT	0x550009	dest = (NOT dest)
BLACKNESS	0x000042	dest = BLACK
WHITENESS	0xFF0062	dest = WHITE

command == 5 Incoming Bit Block Transfer

Transfers a rectangular block of pixels from regular memory into the video memory. The bit block address (bba) is the physical address where the source bit pattern is stored as a sequence of TETRA byte. The current position cur_x, cur_y is the top left coordinate of the destination; the width and height values (w, h) define the size of source and destination rectangle. Clipping (if needed) occurs on the destination rectangle. The command aux value should be used for the raster mode as specified above, (however this is currently not implemented). The values are just copied from source to destination.

The GPU will raise an interrupt when the data transfer has completed.

command == 6 Outgoing Bit Block Transfer

Transfers a rectangular block of pixels from the video memory into regular memory. The current position cur_x, cur_y is the top left coordinate of the source. The width and height values (w, h) define the size of the source and destination rectangle. The bit block address (bba) is the physical address of the destination where the bit pattern is stored as a sequence of TETRA byte. The command aux value should be used for the raster mode as specified above, however, this is currently not implemented. The values are just copied from source to destination.

The GPU will raise an interrupt when the data transfer has completed.

WINVRAM Configuration

The win32 vram device has the following configurable parameters:

host localhost the host where the bus is located

port 9002 the port where the bus is located

address 0x0002000000000000 address where the video ram is located

mouseaddress 0x0001000000000010 address where the mouse device is located

gpuaddress 0x0001000000000020 address where the GPU is located

interrupt 19 interrupt send by the mouse

moveinterrupt false whether mouse movements produce interrupts

gpuinterrupt 20 interrupt send by the GPU

debug false to generate debug output

debugmask 0xFFF0 set mask to hide debug output

verbose false make debugging verbose, sets debug mask to zero

width 640 visible width in pixel

height 480 visible height in pixel

fwidth 640 frame width in pixel

fheight 480 frame height in pixel

fontwidth 10 desired width of characters in pixel

fontheight 20 desired height of characters in pixel

zoom 1 initial zoom factor

define not set to define a name for conditionals

config not set filename for a configuration file

help false to print information

These values can be set in the .vmb file.

host	localhost	the host where the bus is located
port	9002	the port where the bus is located
address	0x0002000000000000	address where the video ram is located
mouseaddress	0x0001000000000010	address where the mouse device is located
gpuaddress	0x0001000000000020	address where the GPU is located
interrupt	19	interrupt send by the mouse
moveinterrupt	false	whether mouse movements produce interrupts
gpuinterrupt	20	interrupt send by the GPU
debug	false	to generate debug output
debugmask	0xFFF0	set mask to hide debug output
verbose	false	make debugging verbose, sets debug mask to zero
width	640	visible width in pixel
height	480	visible height in pixel
fwidth	640	frame width in pixel
fheight	480	frame height in pixel
fontwidth	10	desired width of characters in pixel
fontheight	20	desired height of characters in pixel
zoom	1	initial zoom factor
define	not set	to define a name for conditionals
config	not set	filename for a configuration file
help	false	to print information