Jumpers - Commodore Amiga A4000 User Manual

The Motherboard
The Am iga 4000 has had several revisions including B,D for A4000D and 4 for A4000T. This is the
revision 1 m otherboard:
Chips and Com ponents:
IDE connector - Supports 3.5" Hard drives natively but can support larger 3.5" drives with a converter
ALICE chip - Supports 2MB of Chip RAM, the Blitter and 25 DMA channels (large left hand chip)
GAYLE chip - IDE controller chip (large m iddle chip)
LISA chip - Supports AGA chipset, 256 colours, HAM8, Sprites etc (large right hand chip).
BUDGET chip - Supports DRAM and Bus Controller (Center of board with VLSI on it)
Keyboard MPU - The keyboard controller ship
Motorola 68EC020 - Main Central Processor (surprisingly one of the sm allest chips)
Kickstart ROM Chips - The A1200 had two 256K ROM chips that held part of Am igaOS and allow the
Am iga to boot from Floppy or Hard disk.
DRAM Chips - 2MB of Chip RAM included from NEC
Keyboard connector slot - The white slot on the right
CIA Chip (391078) - Controls ports such as Serial, Parallel and Mouse ports
PAULA (391077) - Controls the sound and the floppy drive
CIA Chip (391078) - Second CIA chip for controlling ports
Floppy drive connector
Jum pers for A4000
Jum per Description
J100 CLK 90 clock source
J104 CPU Clock source
Setting Description
1-2 Internal (020/030)
2-3 External (040)
1-2 Internal
2-3 External
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