Mitsubishi Electric Apricot LS Pro, Техническое описание оборудования

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Chapter 4
Chapter 6
Memory and I/O Usage
Appendix A
Appendix C
Pr
eface
Chapter 4Chapter 5
LS PRO HARDWARE TECHNICAL REFERENCE 5/23
Graphics The graphics controller registers handle the reading, writing and other manipulations
controller of the graphics data.
registers
The registers are accessed by using index and data registers. To access a register, first
write to the index register with the index of the register to be accessed, then write to
the data register with the data to be loaded.
Register Address
Graphics controller index register 03CEh (RWMC)
Graphics controller data register 03CFh (RWMC)
R - read
W - write
M - monochrome
C - colour
The following table shows the index and the registers which can be accessed via the
index.
Register Index
Set/reset 00h
Enable set/reset 01h
Colour compare 02h
Data rotate 03h
Read map select 04h
Graphics mode 05h
Miscellaneous 06h
Colour don’t care 07h
Bit mask 08h
These are standard VGA registers and are not described in further detail here.
Attribute These registers control the screen attributes. In text mode, these are the colour,
controller intensity and blinking of the characters, and the background. In graphics mode, you can
registers select the colour to each pixel.
The four memory planes generate a four bit colour code for each pixel. The colour
plane enable register allows each memory plane to be enabled or disabled.
Each colour code is translated by a palette register into video signals to drive the
monitor.
The attribute controller registers are addressed by a single I/O port address.