Nintendo DMG-01 - Game Boy Console Manual page 55

TM
Game Boy CPU Manual
34. FF43 (SCX)
Name
Contents - Scroll X
35. FF44 (LY)
Name
Contents - LCDC Y-Coordinate (R)
36. FF45 (LYC)
Name
Contents - LY Compare
37. FF46 (DMA)
Name
Contents - DMA Transfer and Start Address (W)
The DMA Transfer (40*28 bit) from internal ROM or
RAM ($0000-$F19F) to the OAM (address $FE00-$FE9F)
by DP
- SCX
8 Bit value $00-$FF to scroll BG X screen
position.
- LY
The LY indicates the vertical line to which
the present data is transferred to the LCD
Driver. The LY can take on any value
between 0 through 153. The values between
144 and 153 indicate the V-Blank period.
Writing will reset the counter.
- LYC
The LYC compares itself with the LY. If the
values are the same it causes the STAT to
set the coincident flag.
- DMA
(R/W)
(R/W)
2.13.1. I/O Registers
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