RLV12 Disk Controller User's Guide

This document is the RLV12 Disk Controller User's Guide, providing a comprehensive overview of the RLV12 Disk Controller and the RL01/RL02 disk drives it supports.

RLV12 Disk Controller:

• Function: Serves as an interface between RL01 (5.24 MB) and RL02 (10.48 MB) random-access disk drives and any quad- or hex-size backplane utilizing a 16-, 18-, or 22-bit LSI-11 bus.
• Capacity: A single RLV12 controller can manage up to four RL01/RL02 disk drives in various combinations.
• Form Factor: It is a single quad-size module (M8061).
• Data Transfer: Employs Direct Memory Access (DMA) transactions for efficient data transfer to and from the LSI-11 bus, bypassing the processor.
• Compatibility: Software compatible with earlier RLV11 controllers (in 16- or 18-bit modes) and fully supports 22-bit LSI-11 addressing.
• Features: Includes robust error detection capabilities like Cyclic Redundancy Check (CRC) on data and headers, and a memory parity error abort feature for systems with parity-checking memory.
• Configuration: It is highly configurable through jumpers for device address, interrupt vector, and memory parity error abort.
• Internal Architecture: Comprises programmable registers (Control/Status, Bus Address, Disk Address, Multipurpose, and Bus Address Extension), FIFO memory for data buffering, and microsequencer-based logic to execute disk commands.

RL01/RL02 Disk Drives:

• Storage: Utilize preformatted, top-loading magnetic disk cartridges for mass storage. RL01 offers 5.24 million bytes, while RL02 offers 10.48 million bytes.
• Physical Characteristics: These are self-cooled, rack-mountable units (26.67 cm high) with integrated power supplies.
• Performance: They operate at 2400 Revolutions Per Minute (RPM), with an average head positioning time of 55 milliseconds. Data is recorded using Modified Frequency Modulation (MFM).
• User Interface: Features front panel switches and indicators (Run/Stop with LOAD, Unit Select with READY, FAULT, WRITE PROTECT), and rear controls for voltage and range settings.

The guide further delves into the functional description of the controller's circuits, detailed explanations of its programmable registers, various commands for disk operations (like Seek, Read/Write Data, Get Status), comprehensive error recovery procedures, and instructions for installation and acceptance testing.