Specifications

CHAPTER 2
Hardware Modifications
8
Changes on Main Logic Board
Figure 2-1 PowerBook Duo 270c main logic board
Integrated Floating-Point Unit 2
The PowerBook Duo 270c computer has an integrated FPU mounted on the main logic
board in a PLCC socket. The FPU is a 68882 device. Figure 2-1 shows the position of the
FPU on the logic board.
Color Control Chip (CSC) 2
The CSC replaces the PowerBook Duo’s gray-scale controller (GSC). Figure 2-1 shows its
position on the main logic board. The CSC is a 144-pin TQFP (thin quad flat pack)
device. It supports FSTN and TFT LCD display panels, in color or monochrome/gray, in
two raster matrix configurations: 640 x 480 and 640 x 400, in dual-drive and single-drive
configurations. It supports the following color and grayscale modes:
■
1 bit per pixel (2 colors or grays), black-and-white monochrome
■
2 bits per pixel (4 colors or grays)
■
4 bits per pixel (16 colors or grays)
■
8 bits per pixel (256 colors or grays)
■
16 bits per pixel (32K colors or grays), with 640 x 400 display
DRAM
expansion
connector
Keyboard
connectors
Test Trackball
Backup
Connectors
Modem
expansion
connector
Serial port
connector
Power
adapter
MSC
Combo
Transformer Transformer
ROM slots
DRAM
DFAC
DRAM
array
152-pin main expansion connector
DRAM
DRAM
DRAM
V
R
A
M
Drawing not to scale
Components that are different for the Escher computer
The logic board contains 8 DRAMs - 4 on each side of the board
MC68030
processor
Power
Manager
Hard drive
CSC
68882
FPU