Amiga Storage Peripherals


SCRAM 2000

> Company: Norman Jackson / MegaMicro, Australia
> Date:
> Amiga: A2000, A3000, A4000
> Interface: Zorro II
> Autoconfig ID: ID4096 / 3,4

Images
SCSI + RAM For A2000, A Public Domain Kitware Project
Schematics, Building Instructions And Driver Software Are All Published
Custom Logic (GALs, PALs, Etc.) Are Not Published, These Chips Have To Be Ordered From The Author
The Five Custom Logic Chips:
Bertie – Controls The Memory Autoconfigure Logic
Cyril – SCSI Autoboot Controller Chip
Griswold – Master Timing Controller For The DRAMs
Ronald – Controls RAM Operation
Dennis – Main Address Decoder

SCSI Controller
Provides Sockets For Either An 8 Or 16 Bit SCSI Controller IC:
National Semiconductor DP8490V – An Enhanced Version Of NCR 53C80
NCR 53C94 – The Card Performs 50% Faster With It
The Two Controllers Require Different Custom Logic Chips And Autoboot ROM
Autoboot ROM – Autobooting Requires Kickstart 1.3
Autoboot Disable Switch For Older Kickstarts Or For Game Compatibility
Supports The Rigid Disk Block Standard
Place For A 3.5 Hard Disk On The Card
Hard Disk Power Connector
50 Pin Internal SCSI Header
External DB25 SCSI Connector
SCSI Access LED Connector
Termination Power Option – Jumper Selectable +5V On Pin 25 Of The External Connector And Pin 26 Of The Internal Header For Using Passive Terminators
Non-DMA Transfer
Custom Synchronising Logic

Memory
16 ZIP Sockets Accept Up To 8 MB RAM
Takes 256kx4 Or 1Mx4 ZIPs
ZIP Sizes Cannot Be Mixed
Possible Configurations Are 0, 2, 4 Or 8 MB
Static Column ZIPs Work, But Not Improve Performance
Zero Wait State
RAM Access LED
Autoconfigure LED