gpu: new font rom designation

This commit is contained in:
minjaesong
2022-06-18 01:41:11 +09:00
parent 12cece8784
commit d103373614

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@@ -170,7 +170,7 @@ From the start of the memory space:
write to this address FIRST and then write to "command" to execute the command
1134 bytes
unused
1920
(1920) !!PENDING FOR REMOVAL!!
mapped to font ROM
Font Mapping area holds 128 characters in consecutive order, each character is always 15 bytes.
(designer's note: it's still useful to divide the char rom to two halves, lower half being characters ROM and upper half being symbols ROM)
@@ -320,6 +320,11 @@ MMIO
framebuffer scroll Y
1024..2047 RW
horizontal scroll offset for scanlines
2048..4095 RW
!!NEW!! Font ROM Mapping Area
Format is always 8x16 pixels, 1bpp ROM format (so that it would be YY_CHR-Compatible)
(designer's note: it's still useful to divide the char rom to two halves, lower half being characters ROM and upper half being symbols ROM)
Text-mode-font-ROM is immutable and does not belong to VRAM
Even in the text mode framebuffer is still being drawn onto the screen, and the texts are drawn on top of it