668-0010 Rabbit Semiconductor, 668-0010 Datasheet - Page 51

• Manufacturer Part Number: 668-0010
• Description: IC MPU RABIT3000 55.5MHZ 128LQFP
• Manufacturer: Rabbit Semiconductor

Specifications of 668-0010

• Rohs Status: RoHS non-compliant
• Processor Type: Rabbit 3000 8-Bit
• Speed: 55.5MHz
• Voltage: 2.5V, 2.7V, 3V, 3.3V
• Mounting Type: Surface Mount
• Package / Case: 128-LQFP
• Features: -
• Other names: 316-1016

The Rabbit 2000 and 3000 have numerous instructions for reading and writing data to
logical addresses, but only limited support for reading and writing data to a physical
memory address.
The 64 KB logical memory space limitation can also be expanded by using the separate
instruction and data space mode. When this mode is enabled, address bit A16 is inverted
for all data accesses in the root and/or data segments, while address bit A19 is inverted for
all data accesses in the root and/or data segments before bank selection (physical device)
occurs. These two features allow both code and data to access separate 64 KB logical
spaces instead of sharing a single space.
It is possible to protect memory in the Rabbit 3000 at three different levels: each of the
memory banks can be made read-only, physical memory can be write-protected in 64 KB
blocks, and two of those 64 KB blocks can be protected with a granularity of 4 KB. A
Priority 3 interrupt will occur if a write is attempted in one of the protected 64 KB or 4 KB
blocks. In addition, it is possible to place limits around the code execution stack and gen-
erate an interrupt if a stack-related write occurs within 16 bytes of those limits.
5.1.1 Block Diagram
Chapter 5 Memory Management
41