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 5/21
General registers The general registers cover a number of miscellaneous hardware functions. They are
used to select the I/O address range, to enable RAM, select dot clock speed, set sync.
signal polarity and write to bits on the feature connector. In the read mode, they give
access to two status registers.
The registers use two port addresses and are listed below:
Register Address
Miscellaneous output register 03C2h (WMC)
03CCh (RMC)
Input status register 0 03C2h (RMC)
Input status register 1 03BAh (RM)
03DAh (RC)
Feature control register 03BAh (WM)
03DAh (WC)
03CAh (RWMC)
R - read
W - Write
M - monochrome
C - colour
These registers are standard VGA registers and are not described in further detail here.
Sequencer The sequencer register controls memory plane selection and shift register timing
registers functions. 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
as the data then write to the data register with the data to be loaded.
Register Address
Sequencer index register 03C4h (RWMC)
Sequencer data register 03C5h (RWMC)
R - read
W - write
M - monochrome
C - colour
The following table shows the index and the registers that are accessed via the index.
Register Index
Reset 00h
Clocking mode 01h
Map mask 02h
Character map select 03h
Memory mode 04h
These are standard VGA registers and are not described in further detail here.