The old code could fail when an OS scroll with start address changes (DLX Linux)
- handle the graphics controller shift register value 3 the same way as 2. We need
a test case for this setting.
#1159639)
- size of text snapshot space increased to 128 kByte (for all memory mappings)
- immediately return after the panic when the number of text lines is too large
to avoid segfault
dummy interface are now disabled if the extension isn't set to "vbe"
- writing charmap data in graphics mode now supported (SF patch #1059199)
- fixed set_ask_format() for the mouse type option
- changes to the original svga_cirrus patch:
* PCI memory/mmio PnP support, some emulation and compile fixes
* ported write mode 4 + 5 and some bufixes from cirrus vga in qemu
* new graphics API, hardware cursor support, configure option added (Robin Kay)
* partial support for transparent bitblt and bitblt write mask
memory handling in memory.cc removed)
- CRTC write protection implemented
- 16-bit read access to some VGA registers added
- memory handler code now conciders the status of the A20 line
bochs.h already not include iodev.h which reduces compilation dependences for almost all cpu and fpu files, now cpu files will not be recompiled if iodev includes was changed
and bpp (done for the x display library)
- new switch VBE_DISPI_GETCAPS. The xres, yres and bpp registers return the gui
capabilities if enabled.
- VBE_DISPI_ID3 defined
The colors 0..7 appear in high intensity and the colors 8..15 blink using
low / high intensity. Blinking is not present in Bochs yet. For now, the 3rd
bit of the attribute will be inverted.
- attribute controller mode control register: only a change of the internal
palette size bit should force a redraw
- skip screen update if video is disabled
plane enable and color select
- a screen update is necessary after updating the charmap
- lots of missing parentheses added (found after disabling VGA_TRACE_FEATURE)
- BX_DEBUG and BX_INFO messages improved
- update function: the 'for' loop now initializes and increments the variables
xti and yti
- VBE: banked writes are now ignored in LFB mode, LFB writes are ignored in
banked mode (based on SF patch #742782)
- calculation of the VBE virtual height for >8bpp fixed
- visible screen size must be recalculated after changing the virtual width
- modify standard VGA register when enabling a VBE mode (some test applications
expect this behaviour)
- BX_INFO messages in the VBE code fixed
- don't clear the VBE memory if the new flag VBE_DISPI_NOCLEARMEM is set
- vbe_bpp_multiplier for the 4bpp mode set to 1 (usually unused, but this value is save)
(using 72 Hz vertical frequency). The vertial retrace phase is often used for
vga register or memory manipulations to reduce screen flickering.
- update(): check variable vga_mem_updated before everything else
(without localized variables)
- start address support for CGA modes added
- start address support for mode 13h completed
- clearing the text snapshot is not necessary after a start address change
(set needs_update to 1 in graphics mode only)
and implemented in SDL
* sequencer controller register 0x01 bit 0 controls the width of the characters.
This value is used to calculate the screen width.
* attribute controller register 0x10 bit 2 controls the appearance of graphics
characters (ASCII 0xC0 - 0cDF). A change of this value forces a charmap update
to rebuild the font bitmaps.
* the SDL display library uses the new feature described above
* the other display libraries recalculate the screen width, since they are using
a fixed font width of 8 for now.
- VGA: attribute controller register 0x10 bit 2 (enable_line_graphics) does not
switch the palatte in CGA mode
ATTENTION: the Elpin VGA BIOS uses a delay of 280 vertical retraces after
displaying the copyright text
- changes to the horizontal or vertical pel panning registers force a redraw of
the screen
- screen update problems in text mode fixed
- sort order of the CRT register write cases changed
- fixed calculation of the byte offset for standard VGA modes if line compare
is active
- force a resize of the screen after a change of the display mode (text/graphics)
- mem_write(): skip the rotation of the cpu byte if 'data_rotate' is 0
If set, the screen size will be horizontally doubled in CGA and standard
VGA modes.
- doublescan feature for CGA mode 320x200x4 added
- removed trailing spaces in VBE update code
